// SPDX-License-Identifier: GPL-2.0-only /* * Kernel-based Virtual Machine driver for Linux * * derived from drivers/kvm/kvm_main.c * * Copyright (C) 2006 Qumranet, Inc. * Copyright (C) 2008 Qumranet, Inc. * Copyright IBM Corporation, 2008 * Copyright 2010 Red Hat, Inc. and/or its affiliates. * * Authors: * Avi Kivity * Yaniv Kamay * Amit Shah * Ben-Ami Yassour */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include "irq.h" #include "ioapic.h" #include "mmu.h" #include "i8254.h" #include "tss.h" #include "kvm_cache_regs.h" #include "kvm_emulate.h" #include "mmu/page_track.h" #include "x86.h" #include "cpuid.h" #include "pmu.h" #include "hyperv.h" #include "lapic.h" #include "xen.h" #include "smm.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define CREATE_TRACE_POINTS #include "trace.h" #define MAX_IO_MSRS 256 #define KVM_MAX_MCE_BANKS 32 struct kvm_caps kvm_caps __read_mostly = { .supported_mce_cap = MCG_CTL_P | MCG_SER_P, }; EXPORT_SYMBOL_GPL(kvm_caps); #define ERR_PTR_USR(e) ((void __user *)ERR_PTR(e)) #define emul_to_vcpu(ctxt) \ ((struct kvm_vcpu *)(ctxt)->vcpu) /* EFER defaults: * - enable syscall per default because its emulated by KVM * - enable LME and LMA per default on 64 bit KVM */ #ifdef CONFIG_X86_64 static u64 __read_mostly efer_reserved_bits = ~((u64)(EFER_SCE | EFER_LME | EFER_LMA)); #else static u64 __read_mostly efer_reserved_bits = ~((u64)EFER_SCE); #endif static u64 __read_mostly cr4_reserved_bits = CR4_RESERVED_BITS; #define KVM_EXIT_HYPERCALL_VALID_MASK (1 << KVM_HC_MAP_GPA_RANGE) #define KVM_CAP_PMU_VALID_MASK KVM_PMU_CAP_DISABLE #define KVM_X2APIC_API_VALID_FLAGS (KVM_X2APIC_API_USE_32BIT_IDS | \ KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK) static void update_cr8_intercept(struct kvm_vcpu *vcpu); static void process_nmi(struct kvm_vcpu *vcpu); static void __kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags); static void store_regs(struct kvm_vcpu *vcpu); static int sync_regs(struct kvm_vcpu *vcpu); static int kvm_vcpu_do_singlestep(struct kvm_vcpu *vcpu); static int __set_sregs2(struct kvm_vcpu *vcpu, struct kvm_sregs2 *sregs2); static void __get_sregs2(struct kvm_vcpu *vcpu, struct kvm_sregs2 *sregs2); static DEFINE_MUTEX(vendor_module_lock); struct kvm_x86_ops kvm_x86_ops __read_mostly; #define KVM_X86_OP(func) \ DEFINE_STATIC_CALL_NULL(kvm_x86_##func, \ *(((struct kvm_x86_ops *)0)->func)); #define KVM_X86_OP_OPTIONAL KVM_X86_OP #define KVM_X86_OP_OPTIONAL_RET0 KVM_X86_OP #include EXPORT_STATIC_CALL_GPL(kvm_x86_get_cs_db_l_bits); EXPORT_STATIC_CALL_GPL(kvm_x86_cache_reg); static bool __read_mostly ignore_msrs = 0; module_param(ignore_msrs, bool, 0644); bool __read_mostly report_ignored_msrs = true; module_param(report_ignored_msrs, bool, 0644); EXPORT_SYMBOL_GPL(report_ignored_msrs); unsigned int min_timer_period_us = 200; module_param(min_timer_period_us, uint, 0644); static bool __read_mostly kvmclock_periodic_sync = true; module_param(kvmclock_periodic_sync, bool, 0444); /* tsc tolerance in parts per million - default to 1/2 of the NTP threshold */ static u32 __read_mostly tsc_tolerance_ppm = 250; module_param(tsc_tolerance_ppm, uint, 0644); /* * lapic timer advance (tscdeadline mode only) in nanoseconds. '-1' enables * adaptive tuning starting from default advancement of 1000ns. '0' disables * advancement entirely. Any other value is used as-is and disables adaptive * tuning, i.e. allows privileged userspace to set an exact advancement time. */ static int __read_mostly lapic_timer_advance_ns = -1; module_param(lapic_timer_advance_ns, int, 0644); static bool __read_mostly vector_hashing = true; module_param(vector_hashing, bool, 0444); bool __read_mostly enable_vmware_backdoor = false; module_param(enable_vmware_backdoor, bool, 0444); EXPORT_SYMBOL_GPL(enable_vmware_backdoor); /* * Flags to manipulate forced emulation behavior (any non-zero value will * enable forced emulation). */ #define KVM_FEP_CLEAR_RFLAGS_RF BIT(1) static int __read_mostly force_emulation_prefix; module_param(force_emulation_prefix, int, 0644); int __read_mostly pi_inject_timer = -1; module_param(pi_inject_timer, bint, 0644); /* Enable/disable PMU virtualization */ bool __read_mostly enable_pmu = true; EXPORT_SYMBOL_GPL(enable_pmu); module_param(enable_pmu, bool, 0444); bool __read_mostly eager_page_split = true; module_param(eager_page_split, bool, 0644); /* Enable/disable SMT_RSB bug mitigation */ static bool __read_mostly mitigate_smt_rsb; module_param(mitigate_smt_rsb, bool, 0444); /* * Restoring the host value for MSRs that are only consumed when running in * usermode, e.g. SYSCALL MSRs and TSC_AUX, can be deferred until the CPU * returns to userspace, i.e. the kernel can run with the guest's value. */ #define KVM_MAX_NR_USER_RETURN_MSRS 16 struct kvm_user_return_msrs { struct user_return_notifier urn; bool registered; struct kvm_user_return_msr_values { u64 host; u64 curr; } values[KVM_MAX_NR_USER_RETURN_MSRS]; }; u32 __read_mostly kvm_nr_uret_msrs; EXPORT_SYMBOL_GPL(kvm_nr_uret_msrs); static u32 __read_mostly kvm_uret_msrs_list[KVM_MAX_NR_USER_RETURN_MSRS]; static struct kvm_user_return_msrs __percpu *user_return_msrs; #define KVM_SUPPORTED_XCR0 (XFEATURE_MASK_FP | XFEATURE_MASK_SSE \ | XFEATURE_MASK_YMM | XFEATURE_MASK_BNDREGS \ | XFEATURE_MASK_BNDCSR | XFEATURE_MASK_AVX512 \ | XFEATURE_MASK_PKRU | XFEATURE_MASK_XTILE) u64 __read_mostly host_efer; EXPORT_SYMBOL_GPL(host_efer); bool __read_mostly allow_smaller_maxphyaddr = 0; EXPORT_SYMBOL_GPL(allow_smaller_maxphyaddr); bool __read_mostly enable_apicv = true; EXPORT_SYMBOL_GPL(enable_apicv); u64 __read_mostly host_xss; EXPORT_SYMBOL_GPL(host_xss); u64 __read_mostly host_arch_capabilities; EXPORT_SYMBOL_GPL(host_arch_capabilities); const struct _kvm_stats_desc kvm_vm_stats_desc[] = { KVM_GENERIC_VM_STATS(), STATS_DESC_COUNTER(VM, mmu_shadow_zapped), STATS_DESC_COUNTER(VM, mmu_pte_write), STATS_DESC_COUNTER(VM, mmu_pde_zapped), STATS_DESC_COUNTER(VM, mmu_flooded), STATS_DESC_COUNTER(VM, mmu_recycled), STATS_DESC_COUNTER(VM, mmu_cache_miss), STATS_DESC_ICOUNTER(VM, mmu_unsync), STATS_DESC_ICOUNTER(VM, pages_4k), STATS_DESC_ICOUNTER(VM, pages_2m), STATS_DESC_ICOUNTER(VM, pages_1g), STATS_DESC_ICOUNTER(VM, nx_lpage_splits), STATS_DESC_PCOUNTER(VM, max_mmu_rmap_size), STATS_DESC_PCOUNTER(VM, max_mmu_page_hash_collisions) }; const struct kvm_stats_header kvm_vm_stats_header = { .name_size = KVM_STATS_NAME_SIZE, .num_desc = ARRAY_SIZE(kvm_vm_stats_desc), .id_offset = sizeof(struct kvm_stats_header), .desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE, .data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE + sizeof(kvm_vm_stats_desc), }; const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = { KVM_GENERIC_VCPU_STATS(), STATS_DESC_COUNTER(VCPU, pf_taken), STATS_DESC_COUNTER(VCPU, pf_fixed), STATS_DESC_COUNTER(VCPU, pf_emulate), STATS_DESC_COUNTER(VCPU, pf_spurious), STATS_DESC_COUNTER(VCPU, pf_fast), STATS_DESC_COUNTER(VCPU, pf_mmio_spte_created), STATS_DESC_COUNTER(VCPU, pf_guest), STATS_DESC_COUNTER(VCPU, tlb_flush), STATS_DESC_COUNTER(VCPU, invlpg), STATS_DESC_COUNTER(VCPU, exits), STATS_DESC_COUNTER(VCPU, io_exits), STATS_DESC_COUNTER(VCPU, mmio_exits), STATS_DESC_COUNTER(VCPU, signal_exits), STATS_DESC_COUNTER(VCPU, irq_window_exits), STATS_DESC_COUNTER(VCPU, nmi_window_exits), STATS_DESC_COUNTER(VCPU, l1d_flush), STATS_DESC_COUNTER(VCPU, halt_exits), STATS_DESC_COUNTER(VCPU, request_irq_exits), STATS_DESC_COUNTER(VCPU, irq_exits), STATS_DESC_COUNTER(VCPU, host_state_reload), STATS_DESC_COUNTER(VCPU, fpu_reload), STATS_DESC_COUNTER(VCPU, insn_emulation), STATS_DESC_COUNTER(VCPU, insn_emulation_fail), STATS_DESC_COUNTER(VCPU, hypercalls), STATS_DESC_COUNTER(VCPU, irq_injections), STATS_DESC_COUNTER(VCPU, nmi_injections), STATS_DESC_COUNTER(VCPU, req_event), STATS_DESC_COUNTER(VCPU, nested_run), STATS_DESC_COUNTER(VCPU, directed_yield_attempted), STATS_DESC_COUNTER(VCPU, directed_yield_successful), STATS_DESC_COUNTER(VCPU, preemption_reported), STATS_DESC_COUNTER(VCPU, preemption_other), STATS_DESC_IBOOLEAN(VCPU, guest_mode), STATS_DESC_COUNTER(VCPU, notify_window_exits), }; const struct kvm_stats_header kvm_vcpu_stats_header = { .name_size = KVM_STATS_NAME_SIZE, .num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc), .id_offset = sizeof(struct kvm_stats_header), .desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE, .data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE + sizeof(kvm_vcpu_stats_desc), }; u64 __read_mostly host_xcr0; static struct kmem_cache *x86_emulator_cache; /* * When called, it means the previous get/set msr reached an invalid msr. * Return true if we want to ignore/silent this failed msr access. */ static bool kvm_msr_ignored_check(u32 msr, u64 data, bool write) { const char *op = write ? "wrmsr" : "rdmsr"; if (ignore_msrs) { if (report_ignored_msrs) kvm_pr_unimpl("ignored %s: 0x%x data 0x%llx\n", op, msr, data); /* Mask the error */ return true; } else { kvm_debug_ratelimited("unhandled %s: 0x%x data 0x%llx\n", op, msr, data); return false; } } static struct kmem_cache *kvm_alloc_emulator_cache(void) { unsigned int useroffset = offsetof(struct x86_emulate_ctxt, src); unsigned int size = sizeof(struct x86_emulate_ctxt); return kmem_cache_create_usercopy("x86_emulator", size, __alignof__(struct x86_emulate_ctxt), SLAB_ACCOUNT, useroffset, size - useroffset, NULL); } static int emulator_fix_hypercall(struct x86_emulate_ctxt *ctxt); static inline void kvm_async_pf_hash_reset(struct kvm_vcpu *vcpu) { int i; for (i = 0; i < ASYNC_PF_PER_VCPU; i++) vcpu->arch.apf.gfns[i] = ~0; } static void kvm_on_user_return(struct user_return_notifier *urn) { unsigned slot; struct kvm_user_return_msrs *msrs = container_of(urn, struct kvm_user_return_msrs, urn); struct kvm_user_return_msr_values *values; unsigned long flags; /* * Disabling irqs at this point since the following code could be * interrupted and executed through kvm_arch_hardware_disable() */ local_irq_save(flags); if (msrs->registered) { msrs->registered = false; user_return_notifier_unregister(urn); } local_irq_restore(flags); for (slot = 0; slot < kvm_nr_uret_msrs; ++slot) { values = &msrs->values[slot]; if (values->host != values->curr) { wrmsrl(kvm_uret_msrs_list[slot], values->host); values->curr = values->host; } } } static int kvm_probe_user_return_msr(u32 msr) { u64 val; int ret; preempt_disable(); ret = rdmsrl_safe(msr, &val); if (ret) goto out; ret = wrmsrl_safe(msr, val); out: preempt_enable(); return ret; } int kvm_add_user_return_msr(u32 msr) { BUG_ON(kvm_nr_uret_msrs >= KVM_MAX_NR_USER_RETURN_MSRS); if (kvm_probe_user_return_msr(msr)) return -1; kvm_uret_msrs_list[kvm_nr_uret_msrs] = msr; return kvm_nr_uret_msrs++; } EXPORT_SYMBOL_GPL(kvm_add_user_return_msr); int kvm_find_user_return_msr(u32 msr) { int i; for (i = 0; i < kvm_nr_uret_msrs; ++i) { if (kvm_uret_msrs_list[i] == msr) return i; } return -1; } EXPORT_SYMBOL_GPL(kvm_find_user_return_msr); static void kvm_user_return_msr_cpu_online(void) { unsigned int cpu = smp_processor_id(); struct kvm_user_return_msrs *msrs = per_cpu_ptr(user_return_msrs, cpu); u64 value; int i; for (i = 0; i < kvm_nr_uret_msrs; ++i) { rdmsrl_safe(kvm_uret_msrs_list[i], &value); msrs->values[i].host = value; msrs->values[i].curr = value; } } int kvm_set_user_return_msr(unsigned slot, u64 value, u64 mask) { unsigned int cpu = smp_processor_id(); struct kvm_user_return_msrs *msrs = per_cpu_ptr(user_return_msrs, cpu); int err; value = (value & mask) | (msrs->values[slot].host & ~mask); if (value == msrs->values[slot].curr) return 0; err = wrmsrl_safe(kvm_uret_msrs_list[slot], value); if (err) return 1; msrs->values[slot].curr = value; if (!msrs->registered) { msrs->urn.on_user_return = kvm_on_user_return; user_return_notifier_register(&msrs->urn); msrs->registered = true; } return 0; } EXPORT_SYMBOL_GPL(kvm_set_user_return_msr); static void drop_user_return_notifiers(void) { unsigned int cpu = smp_processor_id(); struct kvm_user_return_msrs *msrs = per_cpu_ptr(user_return_msrs, cpu); if (msrs->registered) kvm_on_user_return(&msrs->urn); } u64 kvm_get_apic_base(struct kvm_vcpu *vcpu) { return vcpu->arch.apic_base; } enum lapic_mode kvm_get_apic_mode(struct kvm_vcpu *vcpu) { return kvm_apic_mode(kvm_get_apic_base(vcpu)); } EXPORT_SYMBOL_GPL(kvm_get_apic_mode); int kvm_set_apic_base(struct kvm_vcpu *vcpu, struct msr_data *msr_info) { enum lapic_mode old_mode = kvm_get_apic_mode(vcpu); enum lapic_mode new_mode = kvm_apic_mode(msr_info->data); u64 reserved_bits = kvm_vcpu_reserved_gpa_bits_raw(vcpu) | 0x2ff | (guest_cpuid_has(vcpu, X86_FEATURE_X2APIC) ? 0 : X2APIC_ENABLE); if ((msr_info->data & reserved_bits) != 0 || new_mode == LAPIC_MODE_INVALID) return 1; if (!msr_info->host_initiated) { if (old_mode == LAPIC_MODE_X2APIC && new_mode == LAPIC_MODE_XAPIC) return 1; if (old_mode == LAPIC_MODE_DISABLED && new_mode == LAPIC_MODE_X2APIC) return 1; } kvm_lapic_set_base(vcpu, msr_info->data); kvm_recalculate_apic_map(vcpu->kvm); return 0; } /* * Handle a fault on a hardware virtualization (VMX or SVM) instruction. * * Hardware virtualization extension instructions may fault if a reboot turns * off virtualization while processes are running. Usually after catching the * fault we just panic; during reboot instead the instruction is ignored. */ noinstr void kvm_spurious_fault(void) { /* Fault while not rebooting. We want the trace. */ BUG_ON(!kvm_rebooting); } EXPORT_SYMBOL_GPL(kvm_spurious_fault); #define EXCPT_BENIGN 0 #define EXCPT_CONTRIBUTORY 1 #define EXCPT_PF 2 static int exception_class(int vector) { switch (vector) { case PF_VECTOR: return EXCPT_PF; case DE_VECTOR: case TS_VECTOR: case NP_VECTOR: case SS_VECTOR: case GP_VECTOR: return EXCPT_CONTRIBUTORY; default: break; } return EXCPT_BENIGN; } #define EXCPT_FAULT 0 #define EXCPT_TRAP 1 #define EXCPT_ABORT 2 #define EXCPT_INTERRUPT 3 #define EXCPT_DB 4 static int exception_type(int vector) { unsigned int mask; if (WARN_ON(vector > 31 || vector == NMI_VECTOR)) return EXCPT_INTERRUPT; mask = 1 << vector; /* * #DBs can be trap-like or fault-like, the caller must check other CPU * state, e.g. DR6, to determine whether a #DB is a trap or fault. */ if (mask & (1 << DB_VECTOR)) return EXCPT_DB; if (mask & ((1 << BP_VECTOR) | (1 << OF_VECTOR))) return EXCPT_TRAP; if (mask & ((1 << DF_VECTOR) | (1 << MC_VECTOR))) return EXCPT_ABORT; /* Reserved exceptions will result in fault */ return EXCPT_FAULT; } void kvm_deliver_exception_payload(struct kvm_vcpu *vcpu, struct kvm_queued_exception *ex) { if (!ex->has_payload) return; switch (ex->vector) { case DB_VECTOR: /* * "Certain debug exceptions may clear bit 0-3. The * remaining contents of the DR6 register are never * cleared by the processor". */ vcpu->arch.dr6 &= ~DR_TRAP_BITS; /* * In order to reflect the #DB exception payload in guest * dr6, three components need to be considered: active low * bit, FIXED_1 bits and active high bits (e.g. DR6_BD, * DR6_BS and DR6_BT) * DR6_ACTIVE_LOW contains the FIXED_1 and active low bits. * In the target guest dr6: * FIXED_1 bits should always be set. * Active low bits should be cleared if 1-setting in payload. * Active high bits should be set if 1-setting in payload. * * Note, the payload is compatible with the pending debug * exceptions/exit qualification under VMX, that active_low bits * are active high in payload. * So they need to be flipped for DR6. */ vcpu->arch.dr6 |= DR6_ACTIVE_LOW; vcpu->arch.dr6 |= ex->payload; vcpu->arch.dr6 ^= ex->payload & DR6_ACTIVE_LOW; /* * The #DB payload is defined as compatible with the 'pending * debug exceptions' field under VMX, not DR6. While bit 12 is * defined in the 'pending debug exceptions' field (enabled * breakpoint), it is reserved and must be zero in DR6. */ vcpu->arch.dr6 &= ~BIT(12); break; case PF_VECTOR: vcpu->arch.cr2 = ex->payload; break; } ex->has_payload = false; ex->payload = 0; } EXPORT_SYMBOL_GPL(kvm_deliver_exception_payload); static void kvm_queue_exception_vmexit(struct kvm_vcpu *vcpu, unsigned int vector, bool has_error_code, u32 error_code, bool has_payload, unsigned long payload) { struct kvm_queued_exception *ex = &vcpu->arch.exception_vmexit; ex->vector = vector; ex->injected = false; ex->pending = true; ex->has_error_code = has_error_code; ex->error_code = error_code; ex->has_payload = has_payload; ex->payload = payload; } /* Forcibly leave the nested mode in cases like a vCPU reset */ static void kvm_leave_nested(struct kvm_vcpu *vcpu) { kvm_x86_ops.nested_ops->leave_nested(vcpu); } static void kvm_multiple_exception(struct kvm_vcpu *vcpu, unsigned nr, bool has_error, u32 error_code, bool has_payload, unsigned long payload, bool reinject) { u32 prev_nr; int class1, class2; kvm_make_request(KVM_REQ_EVENT, vcpu); /* * If the exception is destined for L2 and isn't being reinjected, * morph it to a VM-Exit if L1 wants to intercept the exception. A * previously injected exception is not checked because it was checked * when it was original queued, and re-checking is incorrect if _L1_ * injected the exception, in which case it's exempt from interception. */ if (!reinject && is_guest_mode(vcpu) && kvm_x86_ops.nested_ops->is_exception_vmexit(vcpu, nr, error_code)) { kvm_queue_exception_vmexit(vcpu, nr, has_error, error_code, has_payload, payload); return; } if (!vcpu->arch.exception.pending && !vcpu->arch.exception.injected) { queue: if (reinject) { /* * On VM-Entry, an exception can be pending if and only * if event injection was blocked by nested_run_pending. * In that case, however, vcpu_enter_guest() requests an * immediate exit, and the guest shouldn't proceed far * enough to need reinjection. */ WARN_ON_ONCE(kvm_is_exception_pending(vcpu)); vcpu->arch.exception.injected = true; if (WARN_ON_ONCE(has_payload)) { /* * A reinjected event has already * delivered its payload. */ has_payload = false; payload = 0; } } else { vcpu->arch.exception.pending = true; vcpu->arch.exception.injected = false; } vcpu->arch.exception.has_error_code = has_error; vcpu->arch.exception.vector = nr; vcpu->arch.exception.error_code = error_code; vcpu->arch.exception.has_payload = has_payload; vcpu->arch.exception.payload = payload; if (!is_guest_mode(vcpu)) kvm_deliver_exception_payload(vcpu, &vcpu->arch.exception); return; } /* to check exception */ prev_nr = vcpu->arch.exception.vector; if (prev_nr == DF_VECTOR) { /* triple fault -> shutdown */ kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu); return; } class1 = exception_class(prev_nr); class2 = exception_class(nr); if ((class1 == EXCPT_CONTRIBUTORY && class2 == EXCPT_CONTRIBUTORY) || (class1 == EXCPT_PF && class2 != EXCPT_BENIGN)) { /* * Synthesize #DF. Clear the previously injected or pending * exception so as not to incorrectly trigger shutdown. */ vcpu->arch.exception.injected = false; vcpu->arch.exception.pending = false; kvm_queue_exception_e(vcpu, DF_VECTOR, 0); } else { /* replace previous exception with a new one in a hope that instruction re-execution will regenerate lost exception */ goto queue; } } void kvm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr) { kvm_multiple_exception(vcpu, nr, false, 0, false, 0, false); } EXPORT_SYMBOL_GPL(kvm_queue_exception); void kvm_requeue_exception(struct kvm_vcpu *vcpu, unsigned nr) { kvm_multiple_exception(vcpu, nr, false, 0, false, 0, true); } EXPORT_SYMBOL_GPL(kvm_requeue_exception); void kvm_queue_exception_p(struct kvm_vcpu *vcpu, unsigned nr, unsigned long payload) { kvm_multiple_exception(vcpu, nr, false, 0, true, payload, false); } EXPORT_SYMBOL_GPL(kvm_queue_exception_p); static void kvm_queue_exception_e_p(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code, unsigned long payload) { kvm_multiple_exception(vcpu, nr, true, error_code, true, payload, false); } int kvm_complete_insn_gp(struct kvm_vcpu *vcpu, int err) { if (err) kvm_inject_gp(vcpu, 0); else return kvm_skip_emulated_instruction(vcpu); return 1; } EXPORT_SYMBOL_GPL(kvm_complete_insn_gp); static int complete_emulated_insn_gp(struct kvm_vcpu *vcpu, int err) { if (err) { kvm_inject_gp(vcpu, 0); return 1; } return kvm_emulate_instruction(vcpu, EMULTYPE_NO_DECODE | EMULTYPE_SKIP | EMULTYPE_COMPLETE_USER_EXIT); } void kvm_inject_page_fault(struct kvm_vcpu *vcpu, struct x86_exception *fault) { ++vcpu->stat.pf_guest; /* * Async #PF in L2 is always forwarded to L1 as a VM-Exit regardless of * whether or not L1 wants to intercept "regular" #PF. */ if (is_guest_mode(vcpu) && fault->async_page_fault) kvm_queue_exception_vmexit(vcpu, PF_VECTOR, true, fault->error_code, true, fault->address); else kvm_queue_exception_e_p(vcpu, PF_VECTOR, fault->error_code, fault->address); } void kvm_inject_emulated_page_fault(struct kvm_vcpu *vcpu, struct x86_exception *fault) { struct kvm_mmu *fault_mmu; WARN_ON_ONCE(fault->vector != PF_VECTOR); fault_mmu = fault->nested_page_fault ? vcpu->arch.mmu : vcpu->arch.walk_mmu; /* * Invalidate the TLB entry for the faulting address, if it exists, * else the access will fault indefinitely (and to emulate hardware). */ if ((fault->error_code & PFERR_PRESENT_MASK) && !(fault->error_code & PFERR_RSVD_MASK)) kvm_mmu_invalidate_addr(vcpu, fault_mmu, fault->address, KVM_MMU_ROOT_CURRENT); fault_mmu->inject_page_fault(vcpu, fault); } EXPORT_SYMBOL_GPL(kvm_inject_emulated_page_fault); void kvm_inject_nmi(struct kvm_vcpu *vcpu) { atomic_inc(&vcpu->arch.nmi_queued); kvm_make_request(KVM_REQ_NMI, vcpu); } void kvm_queue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code) { kvm_multiple_exception(vcpu, nr, true, error_code, false, 0, false); } EXPORT_SYMBOL_GPL(kvm_queue_exception_e); void kvm_requeue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code) { kvm_multiple_exception(vcpu, nr, true, error_code, false, 0, true); } EXPORT_SYMBOL_GPL(kvm_requeue_exception_e); /* * Checks if cpl <= required_cpl; if true, return true. Otherwise queue * a #GP and return false. */ bool kvm_require_cpl(struct kvm_vcpu *vcpu, int required_cpl) { if (static_call(kvm_x86_get_cpl)(vcpu) <= required_cpl) return true; kvm_queue_exception_e(vcpu, GP_VECTOR, 0); return false; } bool kvm_require_dr(struct kvm_vcpu *vcpu, int dr) { if ((dr != 4 && dr != 5) || !kvm_is_cr4_bit_set(vcpu, X86_CR4_DE)) return true; kvm_queue_exception(vcpu, UD_VECTOR); return false; } EXPORT_SYMBOL_GPL(kvm_require_dr); static inline u64 pdptr_rsvd_bits(struct kvm_vcpu *vcpu) { return vcpu->arch.reserved_gpa_bits | rsvd_bits(5, 8) | rsvd_bits(1, 2); } /* * Load the pae pdptrs. Return 1 if they are all valid, 0 otherwise. */ int load_pdptrs(struct kvm_vcpu *vcpu, unsigned long cr3) { struct kvm_mmu *mmu = vcpu->arch.walk_mmu; gfn_t pdpt_gfn = cr3 >> PAGE_SHIFT; gpa_t real_gpa; int i; int ret; u64 pdpte[ARRAY_SIZE(mmu->pdptrs)]; /* * If the MMU is nested, CR3 holds an L2 GPA and needs to be translated * to an L1 GPA. */ real_gpa = kvm_translate_gpa(vcpu, mmu, gfn_to_gpa(pdpt_gfn), PFERR_USER_MASK | PFERR_WRITE_MASK, NULL); if (real_gpa == INVALID_GPA) return 0; /* Note the offset, PDPTRs are 32 byte aligned when using PAE paging. */ ret = kvm_vcpu_read_guest_page(vcpu, gpa_to_gfn(real_gpa), pdpte, cr3 & GENMASK(11, 5), sizeof(pdpte)); if (ret < 0) return 0; for (i = 0; i < ARRAY_SIZE(pdpte); ++i) { if ((pdpte[i] & PT_PRESENT_MASK) && (pdpte[i] & pdptr_rsvd_bits(vcpu))) { return 0; } } /* * Marking VCPU_EXREG_PDPTR dirty doesn't work for !tdp_enabled. * Shadow page roots need to be reconstructed instead. */ if (!tdp_enabled && memcmp(mmu->pdptrs, pdpte, sizeof(mmu->pdptrs))) kvm_mmu_free_roots(vcpu->kvm, mmu, KVM_MMU_ROOT_CURRENT); memcpy(mmu->pdptrs, pdpte, sizeof(mmu->pdptrs)); kvm_register_mark_dirty(vcpu, VCPU_EXREG_PDPTR); kvm_make_request(KVM_REQ_LOAD_MMU_PGD, vcpu); vcpu->arch.pdptrs_from_userspace = false; return 1; } EXPORT_SYMBOL_GPL(load_pdptrs); static bool kvm_is_valid_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) { #ifdef CONFIG_X86_64 if (cr0 & 0xffffffff00000000UL) return false; #endif if ((cr0 & X86_CR0_NW) && !(cr0 & X86_CR0_CD)) return false; if ((cr0 & X86_CR0_PG) && !(cr0 & X86_CR0_PE)) return false; return static_call(kvm_x86_is_valid_cr0)(vcpu, cr0); } void kvm_post_set_cr0(struct kvm_vcpu *vcpu, unsigned long old_cr0, unsigned long cr0) { /* * CR0.WP is incorporated into the MMU role, but only for non-nested, * indirect shadow MMUs. If paging is disabled, no updates are needed * as there are no permission bits to emulate. If TDP is enabled, the * MMU's metadata needs to be updated, e.g. so that emulating guest * translations does the right thing, but there's no need to unload the * root as CR0.WP doesn't affect SPTEs. */ if ((cr0 ^ old_cr0) == X86_CR0_WP) { if (!(cr0 & X86_CR0_PG)) return; if (tdp_enabled) { kvm_init_mmu(vcpu); return; } } if ((cr0 ^ old_cr0) & X86_CR0_PG) { kvm_clear_async_pf_completion_queue(vcpu); kvm_async_pf_hash_reset(vcpu); /* * Clearing CR0.PG is defined to flush the TLB from the guest's * perspective. */ if (!(cr0 & X86_CR0_PG)) kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu); } if ((cr0 ^ old_cr0) & KVM_MMU_CR0_ROLE_BITS) kvm_mmu_reset_context(vcpu); if (((cr0 ^ old_cr0) & X86_CR0_CD) && kvm_mmu_honors_guest_mtrrs(vcpu->kvm) && !kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_CD_NW_CLEARED)) kvm_zap_gfn_range(vcpu->kvm, 0, ~0ULL); } EXPORT_SYMBOL_GPL(kvm_post_set_cr0); int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) { unsigned long old_cr0 = kvm_read_cr0(vcpu); if (!kvm_is_valid_cr0(vcpu, cr0)) return 1; cr0 |= X86_CR0_ET; /* Write to CR0 reserved bits are ignored, even on Intel. */ cr0 &= ~CR0_RESERVED_BITS; #ifdef CONFIG_X86_64 if ((vcpu->arch.efer & EFER_LME) && !is_paging(vcpu) && (cr0 & X86_CR0_PG)) { int cs_db, cs_l; if (!is_pae(vcpu)) return 1; static_call(kvm_x86_get_cs_db_l_bits)(vcpu, &cs_db, &cs_l); if (cs_l) return 1; } #endif if (!(vcpu->arch.efer & EFER_LME) && (cr0 & X86_CR0_PG) && is_pae(vcpu) && ((cr0 ^ old_cr0) & X86_CR0_PDPTR_BITS) && !load_pdptrs(vcpu, kvm_read_cr3(vcpu))) return 1; if (!(cr0 & X86_CR0_PG) && (is_64_bit_mode(vcpu) || kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE))) return 1; static_call(kvm_x86_set_cr0)(vcpu, cr0); kvm_post_set_cr0(vcpu, old_cr0, cr0); return 0; } EXPORT_SYMBOL_GPL(kvm_set_cr0); void kvm_lmsw(struct kvm_vcpu *vcpu, unsigned long msw) { (void)kvm_set_cr0(vcpu, kvm_read_cr0_bits(vcpu, ~0x0eul) | (msw & 0x0f)); } EXPORT_SYMBOL_GPL(kvm_lmsw); void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu) { if (vcpu->arch.guest_state_protected) return; if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) { if (vcpu->arch.xcr0 != host_xcr0) xsetbv(XCR_XFEATURE_ENABLED_MASK, vcpu->arch.xcr0); if (guest_can_use(vcpu, X86_FEATURE_XSAVES) && vcpu->arch.ia32_xss != host_xss) wrmsrl(MSR_IA32_XSS, vcpu->arch.ia32_xss); } if (cpu_feature_enabled(X86_FEATURE_PKU) && vcpu->arch.pkru != vcpu->arch.host_pkru && ((vcpu->arch.xcr0 & XFEATURE_MASK_PKRU) || kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE))) write_pkru(vcpu->arch.pkru); } EXPORT_SYMBOL_GPL(kvm_load_guest_xsave_state); void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu) { if (vcpu->arch.guest_state_protected) return; if (cpu_feature_enabled(X86_FEATURE_PKU) && ((vcpu->arch.xcr0 & XFEATURE_MASK_PKRU) || kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE))) { vcpu->arch.pkru = rdpkru(); if (vcpu->arch.pkru != vcpu->arch.host_pkru) write_pkru(vcpu->arch.host_pkru); } if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) { if (vcpu->arch.xcr0 != host_xcr0) xsetbv(XCR_XFEATURE_ENABLED_MASK, host_xcr0); if (guest_can_use(vcpu, X86_FEATURE_XSAVES) && vcpu->arch.ia32_xss != host_xss) wrmsrl(MSR_IA32_XSS, host_xss); } } EXPORT_SYMBOL_GPL(kvm_load_host_xsave_state); #ifdef CONFIG_X86_64 static inline u64 kvm_guest_supported_xfd(struct kvm_vcpu *vcpu) { return vcpu->arch.guest_supported_xcr0 & XFEATURE_MASK_USER_DYNAMIC; } #endif static int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr) { u64 xcr0 = xcr; u64 old_xcr0 = vcpu->arch.xcr0; u64 valid_bits; /* Only support XCR_XFEATURE_ENABLED_MASK(xcr0) now */ if (index != XCR_XFEATURE_ENABLED_MASK) return 1; if (!(xcr0 & XFEATURE_MASK_FP)) return 1; if ((xcr0 & XFEATURE_MASK_YMM) && !(xcr0 & XFEATURE_MASK_SSE)) return 1; /* * Do not allow the guest to set bits that we do not support * saving. However, xcr0 bit 0 is always set, even if the * emulated CPU does not support XSAVE (see kvm_vcpu_reset()). */ valid_bits = vcpu->arch.guest_supported_xcr0 | XFEATURE_MASK_FP; if (xcr0 & ~valid_bits) return 1; if ((!(xcr0 & XFEATURE_MASK_BNDREGS)) != (!(xcr0 & XFEATURE_MASK_BNDCSR))) return 1; if (xcr0 & XFEATURE_MASK_AVX512) { if (!(xcr0 & XFEATURE_MASK_YMM)) return 1; if ((xcr0 & XFEATURE_MASK_AVX512) != XFEATURE_MASK_AVX512) return 1; } if ((xcr0 & XFEATURE_MASK_XTILE) && ((xcr0 & XFEATURE_MASK_XTILE) != XFEATURE_MASK_XTILE)) return 1; vcpu->arch.xcr0 = xcr0; if ((xcr0 ^ old_xcr0) & XFEATURE_MASK_EXTEND) kvm_update_cpuid_runtime(vcpu); return 0; } int kvm_emulate_xsetbv(struct kvm_vcpu *vcpu) { /* Note, #UD due to CR4.OSXSAVE=0 has priority over the intercept. */ if (static_call(kvm_x86_get_cpl)(vcpu) != 0 || __kvm_set_xcr(vcpu, kvm_rcx_read(vcpu), kvm_read_edx_eax(vcpu))) { kvm_inject_gp(vcpu, 0); return 1; } return kvm_skip_emulated_instruction(vcpu); } EXPORT_SYMBOL_GPL(kvm_emulate_xsetbv); bool __kvm_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) { if (cr4 & cr4_reserved_bits) return false; if (cr4 & vcpu->arch.cr4_guest_rsvd_bits) return false; return true; } EXPORT_SYMBOL_GPL(__kvm_is_valid_cr4); static bool kvm_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) { return __kvm_is_valid_cr4(vcpu, cr4) && static_call(kvm_x86_is_valid_cr4)(vcpu, cr4); } void kvm_post_set_cr4(struct kvm_vcpu *vcpu, unsigned long old_cr4, unsigned long cr4) { if ((cr4 ^ old_cr4) & KVM_MMU_CR4_ROLE_BITS) kvm_mmu_reset_context(vcpu); /* * If CR4.PCIDE is changed 0 -> 1, there is no need to flush the TLB * according to the SDM; however, stale prev_roots could be reused * incorrectly in the future after a MOV to CR3 with NOFLUSH=1, so we * free them all. This is *not* a superset of KVM_REQ_TLB_FLUSH_GUEST * or KVM_REQ_TLB_FLUSH_CURRENT, because the hardware TLB is not flushed, * so fall through. */ if (!tdp_enabled && (cr4 & X86_CR4_PCIDE) && !(old_cr4 & X86_CR4_PCIDE)) kvm_mmu_unload(vcpu); /* * The TLB has to be flushed for all PCIDs if any of the following * (architecturally required) changes happen: * - CR4.PCIDE is changed from 1 to 0 * - CR4.PGE is toggled * * This is a superset of KVM_REQ_TLB_FLUSH_CURRENT. */ if (((cr4 ^ old_cr4) & X86_CR4_PGE) || (!(cr4 & X86_CR4_PCIDE) && (old_cr4 & X86_CR4_PCIDE))) kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu); /* * The TLB has to be flushed for the current PCID if any of the * following (architecturally required) changes happen: * - CR4.SMEP is changed from 0 to 1 * - CR4.PAE is toggled */ else if (((cr4 ^ old_cr4) & X86_CR4_PAE) || ((cr4 & X86_CR4_SMEP) && !(old_cr4 & X86_CR4_SMEP))) kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu); } EXPORT_SYMBOL_GPL(kvm_post_set_cr4); int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) { unsigned long old_cr4 = kvm_read_cr4(vcpu); if (!kvm_is_valid_cr4(vcpu, cr4)) return 1; if (is_long_mode(vcpu)) { if (!(cr4 & X86_CR4_PAE)) return 1; if ((cr4 ^ old_cr4) & X86_CR4_LA57) return 1; } else if (is_paging(vcpu) && (cr4 & X86_CR4_PAE) && ((cr4 ^ old_cr4) & X86_CR4_PDPTR_BITS) && !load_pdptrs(vcpu, kvm_read_cr3(vcpu))) return 1; if ((cr4 & X86_CR4_PCIDE) && !(old_cr4 & X86_CR4_PCIDE)) { /* PCID can not be enabled when cr3[11:0]!=000H or EFER.LMA=0 */ if ((kvm_read_cr3(vcpu) & X86_CR3_PCID_MASK) || !is_long_mode(vcpu)) return 1; } static_call(kvm_x86_set_cr4)(vcpu, cr4); kvm_post_set_cr4(vcpu, old_cr4, cr4); return 0; } EXPORT_SYMBOL_GPL(kvm_set_cr4); static void kvm_invalidate_pcid(struct kvm_vcpu *vcpu, unsigned long pcid) { struct kvm_mmu *mmu = vcpu->arch.mmu; unsigned long roots_to_free = 0; int i; /* * MOV CR3 and INVPCID are usually not intercepted when using TDP, but * this is reachable when running EPT=1 and unrestricted_guest=0, and * also via the emulator. KVM's TDP page tables are not in the scope of * the invalidation, but the guest's TLB entries need to be flushed as * the CPU may have cached entries in its TLB for the target PCID. */ if (unlikely(tdp_enabled)) { kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu); return; } /* * If neither the current CR3 nor any of the prev_roots use the given * PCID, then nothing needs to be done here because a resync will * happen anyway before switching to any other CR3. */ if (kvm_get_active_pcid(vcpu) == pcid) { kvm_make_request(KVM_REQ_MMU_SYNC, vcpu); kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu); } /* * If PCID is disabled, there is no need to free prev_roots even if the * PCIDs for them are also 0, because MOV to CR3 always flushes the TLB * with PCIDE=0. */ if (!kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE)) return; for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) if (kvm_get_pcid(vcpu, mmu->prev_roots[i].pgd) == pcid) roots_to_free |= KVM_MMU_ROOT_PREVIOUS(i); kvm_mmu_free_roots(vcpu->kvm, mmu, roots_to_free); } int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3) { bool skip_tlb_flush = false; unsigned long pcid = 0; #ifdef CONFIG_X86_64 if (kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE)) { skip_tlb_flush = cr3 & X86_CR3_PCID_NOFLUSH; cr3 &= ~X86_CR3_PCID_NOFLUSH; pcid = cr3 & X86_CR3_PCID_MASK; } #endif /* PDPTRs are always reloaded for PAE paging. */ if (cr3 == kvm_read_cr3(vcpu) && !is_pae_paging(vcpu)) goto handle_tlb_flush; /* * Do not condition the GPA check on long mode, this helper is used to * stuff CR3, e.g. for RSM emulation, and there is no guarantee that * the current vCPU mode is accurate. */ if (!kvm_vcpu_is_legal_cr3(vcpu, cr3)) return 1; if (is_pae_paging(vcpu) && !load_pdptrs(vcpu, cr3)) return 1; if (cr3 != kvm_read_cr3(vcpu)) kvm_mmu_new_pgd(vcpu, cr3); vcpu->arch.cr3 = cr3; kvm_register_mark_dirty(vcpu, VCPU_EXREG_CR3); /* Do not call post_set_cr3, we do not get here for confidential guests. */ handle_tlb_flush: /* * A load of CR3 that flushes the TLB flushes only the current PCID, * even if PCID is disabled, in which case PCID=0 is flushed. It's a * moot point in the end because _disabling_ PCID will flush all PCIDs, * and it's impossible to use a non-zero PCID when PCID is disabled, * i.e. only PCID=0 can be relevant. */ if (!skip_tlb_flush) kvm_invalidate_pcid(vcpu, pcid); return 0; } EXPORT_SYMBOL_GPL(kvm_set_cr3); int kvm_set_cr8(struct kvm_vcpu *vcpu, unsigned long cr8) { if (cr8 & CR8_RESERVED_BITS) return 1; if (lapic_in_kernel(vcpu)) kvm_lapic_set_tpr(vcpu, cr8); else vcpu->arch.cr8 = cr8; return 0; } EXPORT_SYMBOL_GPL(kvm_set_cr8); unsigned long kvm_get_cr8(struct kvm_vcpu *vcpu) { if (lapic_in_kernel(vcpu)) return kvm_lapic_get_cr8(vcpu); else return vcpu->arch.cr8; } EXPORT_SYMBOL_GPL(kvm_get_cr8); static void kvm_update_dr0123(struct kvm_vcpu *vcpu) { int i; if (!(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP)) { for (i = 0; i < KVM_NR_DB_REGS; i++) vcpu->arch.eff_db[i] = vcpu->arch.db[i]; } } void kvm_update_dr7(struct kvm_vcpu *vcpu) { unsigned long dr7; if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP) dr7 = vcpu->arch.guest_debug_dr7; else dr7 = vcpu->arch.dr7; static_call(kvm_x86_set_dr7)(vcpu, dr7); vcpu->arch.switch_db_regs &= ~KVM_DEBUGREG_BP_ENABLED; if (dr7 & DR7_BP_EN_MASK) vcpu->arch.switch_db_regs |= KVM_DEBUGREG_BP_ENABLED; } EXPORT_SYMBOL_GPL(kvm_update_dr7); static u64 kvm_dr6_fixed(struct kvm_vcpu *vcpu) { u64 fixed = DR6_FIXED_1; if (!guest_cpuid_has(vcpu, X86_FEATURE_RTM)) fixed |= DR6_RTM; if (!guest_cpuid_has(vcpu, X86_FEATURE_BUS_LOCK_DETECT)) fixed |= DR6_BUS_LOCK; return fixed; } int kvm_set_dr(struct kvm_vcpu *vcpu, int dr, unsigned long val) { size_t size = ARRAY_SIZE(vcpu->arch.db); switch (dr) { case 0 ... 3: vcpu->arch.db[array_index_nospec(dr, size)] = val; if (!(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP)) vcpu->arch.eff_db[dr] = val; break; case 4: case 6: if (!kvm_dr6_valid(val)) return 1; /* #GP */ vcpu->arch.dr6 = (val & DR6_VOLATILE) | kvm_dr6_fixed(vcpu); break; case 5: default: /* 7 */ if (!kvm_dr7_valid(val)) return 1; /* #GP */ vcpu->arch.dr7 = (val & DR7_VOLATILE) | DR7_FIXED_1; kvm_update_dr7(vcpu); break; } return 0; } EXPORT_SYMBOL_GPL(kvm_set_dr); unsigned long kvm_get_dr(struct kvm_vcpu *vcpu, int dr) { size_t size = ARRAY_SIZE(vcpu->arch.db); switch (dr) { case 0 ... 3: return vcpu->arch.db[array_index_nospec(dr, size)]; case 4: case 6: return vcpu->arch.dr6; case 5: default: /* 7 */ return vcpu->arch.dr7; } } EXPORT_SYMBOL_GPL(kvm_get_dr); int kvm_emulate_rdpmc(struct kvm_vcpu *vcpu) { u32 ecx = kvm_rcx_read(vcpu); u64 data; if (kvm_pmu_rdpmc(vcpu, ecx, &data)) { kvm_inject_gp(vcpu, 0); return 1; } kvm_rax_write(vcpu, (u32)data); kvm_rdx_write(vcpu, data >> 32); return kvm_skip_emulated_instruction(vcpu); } EXPORT_SYMBOL_GPL(kvm_emulate_rdpmc); /* * The three MSR lists(msrs_to_save, emulated_msrs, msr_based_features) track * the set of MSRs that KVM exposes to userspace through KVM_GET_MSRS, * KVM_SET_MSRS, and KVM_GET_MSR_INDEX_LIST. msrs_to_save holds MSRs that * require host support, i.e. should be probed via RDMSR. emulated_msrs holds * MSRs that KVM emulates without strictly requiring host support. * msr_based_features holds MSRs that enumerate features, i.e. are effectively * CPUID leafs. Note, msr_based_features isn't mutually exclusive with * msrs_to_save and emulated_msrs. */ static const u32 msrs_to_save_base[] = { MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, MSR_IA32_SYSENTER_EIP, MSR_STAR, #ifdef CONFIG_X86_64 MSR_CSTAR, MSR_KERNEL_GS_BASE, MSR_SYSCALL_MASK, MSR_LSTAR, #endif MSR_IA32_TSC, MSR_IA32_CR_PAT, MSR_VM_HSAVE_PA, MSR_IA32_FEAT_CTL, MSR_IA32_BNDCFGS, MSR_TSC_AUX, MSR_IA32_SPEC_CTRL, MSR_IA32_TSX_CTRL, MSR_IA32_RTIT_CTL, MSR_IA32_RTIT_STATUS, MSR_IA32_RTIT_CR3_MATCH, MSR_IA32_RTIT_OUTPUT_BASE, MSR_IA32_RTIT_OUTPUT_MASK, MSR_IA32_RTIT_ADDR0_A, MSR_IA32_RTIT_ADDR0_B, MSR_IA32_RTIT_ADDR1_A, MSR_IA32_RTIT_ADDR1_B, MSR_IA32_RTIT_ADDR2_A, MSR_IA32_RTIT_ADDR2_B, MSR_IA32_RTIT_ADDR3_A, MSR_IA32_RTIT_ADDR3_B, MSR_IA32_UMWAIT_CONTROL, MSR_IA32_XFD, MSR_IA32_XFD_ERR, }; static const u32 msrs_to_save_pmu[] = { MSR_ARCH_PERFMON_FIXED_CTR0, MSR_ARCH_PERFMON_FIXED_CTR1, MSR_ARCH_PERFMON_FIXED_CTR0 + 2, MSR_CORE_PERF_FIXED_CTR_CTRL, MSR_CORE_PERF_GLOBAL_STATUS, MSR_CORE_PERF_GLOBAL_CTRL, MSR_CORE_PERF_GLOBAL_OVF_CTRL, MSR_IA32_PEBS_ENABLE, MSR_IA32_DS_AREA, MSR_PEBS_DATA_CFG, /* This part of MSRs should match KVM_INTEL_PMC_MAX_GENERIC. */ MSR_ARCH_PERFMON_PERFCTR0, MSR_ARCH_PERFMON_PERFCTR1, MSR_ARCH_PERFMON_PERFCTR0 + 2, MSR_ARCH_PERFMON_PERFCTR0 + 3, MSR_ARCH_PERFMON_PERFCTR0 + 4, MSR_ARCH_PERFMON_PERFCTR0 + 5, MSR_ARCH_PERFMON_PERFCTR0 + 6, MSR_ARCH_PERFMON_PERFCTR0 + 7, MSR_ARCH_PERFMON_EVENTSEL0, MSR_ARCH_PERFMON_EVENTSEL1, MSR_ARCH_PERFMON_EVENTSEL0 + 2, MSR_ARCH_PERFMON_EVENTSEL0 + 3, MSR_ARCH_PERFMON_EVENTSEL0 + 4, MSR_ARCH_PERFMON_EVENTSEL0 + 5, MSR_ARCH_PERFMON_EVENTSEL0 + 6, MSR_ARCH_PERFMON_EVENTSEL0 + 7, MSR_K7_EVNTSEL0, MSR_K7_EVNTSEL1, MSR_K7_EVNTSEL2, MSR_K7_EVNTSEL3, MSR_K7_PERFCTR0, MSR_K7_PERFCTR1, MSR_K7_PERFCTR2, MSR_K7_PERFCTR3, /* This part of MSRs should match KVM_AMD_PMC_MAX_GENERIC. */ MSR_F15H_PERF_CTL0, MSR_F15H_PERF_CTL1, MSR_F15H_PERF_CTL2, MSR_F15H_PERF_CTL3, MSR_F15H_PERF_CTL4, MSR_F15H_PERF_CTL5, MSR_F15H_PERF_CTR0, MSR_F15H_PERF_CTR1, MSR_F15H_PERF_CTR2, MSR_F15H_PERF_CTR3, MSR_F15H_PERF_CTR4, MSR_F15H_PERF_CTR5, MSR_AMD64_PERF_CNTR_GLOBAL_CTL, MSR_AMD64_PERF_CNTR_GLOBAL_STATUS, MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR, }; static u32 msrs_to_save[ARRAY_SIZE(msrs_to_save_base) + ARRAY_SIZE(msrs_to_save_pmu)]; static unsigned num_msrs_to_save; static const u32 emulated_msrs_all[] = { MSR_KVM_SYSTEM_TIME, MSR_KVM_WALL_CLOCK, MSR_KVM_SYSTEM_TIME_NEW, MSR_KVM_WALL_CLOCK_NEW, #ifdef CONFIG_KVM_HYPERV HV_X64_MSR_GUEST_OS_ID, HV_X64_MSR_HYPERCALL, HV_X64_MSR_TIME_REF_COUNT, HV_X64_MSR_REFERENCE_TSC, HV_X64_MSR_TSC_FREQUENCY, HV_X64_MSR_APIC_FREQUENCY, HV_X64_MSR_CRASH_P0, HV_X64_MSR_CRASH_P1, HV_X64_MSR_CRASH_P2, HV_X64_MSR_CRASH_P3, HV_X64_MSR_CRASH_P4, HV_X64_MSR_CRASH_CTL, HV_X64_MSR_RESET, HV_X64_MSR_VP_INDEX, HV_X64_MSR_VP_RUNTIME, HV_X64_MSR_SCONTROL, HV_X64_MSR_STIMER0_CONFIG, HV_X64_MSR_VP_ASSIST_PAGE, HV_X64_MSR_REENLIGHTENMENT_CONTROL, HV_X64_MSR_TSC_EMULATION_CONTROL, HV_X64_MSR_TSC_EMULATION_STATUS, HV_X64_MSR_TSC_INVARIANT_CONTROL, HV_X64_MSR_SYNDBG_OPTIONS, HV_X64_MSR_SYNDBG_CONTROL, HV_X64_MSR_SYNDBG_STATUS, HV_X64_MSR_SYNDBG_SEND_BUFFER, HV_X64_MSR_SYNDBG_RECV_BUFFER, HV_X64_MSR_SYNDBG_PENDING_BUFFER, #endif MSR_KVM_ASYNC_PF_EN, MSR_KVM_STEAL_TIME, MSR_KVM_PV_EOI_EN, MSR_KVM_ASYNC_PF_INT, MSR_KVM_ASYNC_PF_ACK, MSR_IA32_TSC_ADJUST, MSR_IA32_TSC_DEADLINE, MSR_IA32_ARCH_CAPABILITIES, MSR_IA32_PERF_CAPABILITIES, MSR_IA32_MISC_ENABLE, MSR_IA32_MCG_STATUS, MSR_IA32_MCG_CTL, MSR_IA32_MCG_EXT_CTL, MSR_IA32_SMBASE, MSR_SMI_COUNT, MSR_PLATFORM_INFO, MSR_MISC_FEATURES_ENABLES, MSR_AMD64_VIRT_SPEC_CTRL, MSR_AMD64_TSC_RATIO, MSR_IA32_POWER_CTL, MSR_IA32_UCODE_REV, /* * KVM always supports the "true" VMX control MSRs, even if the host * does not. The VMX MSRs as a whole are considered "emulated" as KVM * doesn't strictly require them to exist in the host (ignoring that * KVM would refuse to load in the first place if the core set of MSRs * aren't supported). */ MSR_IA32_VMX_BASIC, MSR_IA32_VMX_TRUE_PINBASED_CTLS, MSR_IA32_VMX_TRUE_PROCBASED_CTLS, MSR_IA32_VMX_TRUE_EXIT_CTLS, MSR_IA32_VMX_TRUE_ENTRY_CTLS, MSR_IA32_VMX_MISC, MSR_IA32_VMX_CR0_FIXED0, MSR_IA32_VMX_CR4_FIXED0, MSR_IA32_VMX_VMCS_ENUM, MSR_IA32_VMX_PROCBASED_CTLS2, MSR_IA32_VMX_EPT_VPID_CAP, MSR_IA32_VMX_VMFUNC, MSR_K7_HWCR, MSR_KVM_POLL_CONTROL, }; static u32 emulated_msrs[ARRAY_SIZE(emulated_msrs_all)]; static unsigned num_emulated_msrs; /* * List of MSRs that control the existence of MSR-based features, i.e. MSRs * that are effectively CPUID leafs. VMX MSRs are also included in the set of * feature MSRs, but are handled separately to allow expedited lookups. */ static const u32 msr_based_features_all_except_vmx[] = { MSR_AMD64_DE_CFG, MSR_IA32_UCODE_REV, MSR_IA32_ARCH_CAPABILITIES, MSR_IA32_PERF_CAPABILITIES, }; static u32 msr_based_features[ARRAY_SIZE(msr_based_features_all_except_vmx) + (KVM_LAST_EMULATED_VMX_MSR - KVM_FIRST_EMULATED_VMX_MSR + 1)]; static unsigned int num_msr_based_features; /* * All feature MSRs except uCode revID, which tracks the currently loaded uCode * patch, are immutable once the vCPU model is defined. */ static bool kvm_is_immutable_feature_msr(u32 msr) { int i; if (msr >= KVM_FIRST_EMULATED_VMX_MSR && msr <= KVM_LAST_EMULATED_VMX_MSR) return true; for (i = 0; i < ARRAY_SIZE(msr_based_features_all_except_vmx); i++) { if (msr == msr_based_features_all_except_vmx[i]) return msr != MSR_IA32_UCODE_REV; } return false; } /* * Some IA32_ARCH_CAPABILITIES bits have dependencies on MSRs that KVM * does not yet virtualize. These include: * 10 - MISC_PACKAGE_CTRLS * 11 - ENERGY_FILTERING_CTL * 12 - DOITM * 18 - FB_CLEAR_CTRL * 21 - XAPIC_DISABLE_STATUS * 23 - OVERCLOCKING_STATUS */ #define KVM_SUPPORTED_ARCH_CAP \ (ARCH_CAP_RDCL_NO | ARCH_CAP_IBRS_ALL | ARCH_CAP_RSBA | \ ARCH_CAP_SKIP_VMENTRY_L1DFLUSH | ARCH_CAP_SSB_NO | ARCH_CAP_MDS_NO | \ ARCH_CAP_PSCHANGE_MC_NO | ARCH_CAP_TSX_CTRL_MSR | ARCH_CAP_TAA_NO | \ ARCH_CAP_SBDR_SSDP_NO | ARCH_CAP_FBSDP_NO | ARCH_CAP_PSDP_NO | \ ARCH_CAP_FB_CLEAR | ARCH_CAP_RRSBA | ARCH_CAP_PBRSB_NO | ARCH_CAP_GDS_NO) static u64 kvm_get_arch_capabilities(void) { u64 data = host_arch_capabilities & KVM_SUPPORTED_ARCH_CAP; /* * If nx_huge_pages is enabled, KVM's shadow paging will ensure that * the nested hypervisor runs with NX huge pages. If it is not, * L1 is anyway vulnerable to ITLB_MULTIHIT exploits from other * L1 guests, so it need not worry about its own (L2) guests. */ data |= ARCH_CAP_PSCHANGE_MC_NO; /* * If we're doing cache flushes (either "always" or "cond") * we will do one whenever the guest does a vmlaunch/vmresume. * If an outer hypervisor is doing the cache flush for us * (ARCH_CAP_SKIP_VMENTRY_L1DFLUSH), we can safely pass that * capability to the guest too, and if EPT is disabled we're not * vulnerable. Overall, only VMENTER_L1D_FLUSH_NEVER will * require a nested hypervisor to do a flush of its own. */ if (l1tf_vmx_mitigation != VMENTER_L1D_FLUSH_NEVER) data |= ARCH_CAP_SKIP_VMENTRY_L1DFLUSH; if (!boot_cpu_has_bug(X86_BUG_CPU_MELTDOWN)) data |= ARCH_CAP_RDCL_NO; if (!boot_cpu_has_bug(X86_BUG_SPEC_STORE_BYPASS)) data |= ARCH_CAP_SSB_NO; if (!boot_cpu_has_bug(X86_BUG_MDS)) data |= ARCH_CAP_MDS_NO; if (!boot_cpu_has(X86_FEATURE_RTM)) { /* * If RTM=0 because the kernel has disabled TSX, the host might * have TAA_NO or TSX_CTRL. Clear TAA_NO (the guest sees RTM=0 * and therefore knows that there cannot be TAA) but keep * TSX_CTRL: some buggy userspaces leave it set on tsx=on hosts, * and we want to allow migrating those guests to tsx=off hosts. */ data &= ~ARCH_CAP_TAA_NO; } else if (!boot_cpu_has_bug(X86_BUG_TAA)) { data |= ARCH_CAP_TAA_NO; } else { /* * Nothing to do here; we emulate TSX_CTRL if present on the * host so the guest can choose between disabling TSX or * using VERW to clear CPU buffers. */ } if (!boot_cpu_has_bug(X86_BUG_GDS) || gds_ucode_mitigated()) data |= ARCH_CAP_GDS_NO; return data; } static int kvm_get_msr_feature(struct kvm_msr_entry *msr) { switch (msr->index) { case MSR_IA32_ARCH_CAPABILITIES: msr->data = kvm_get_arch_capabilities(); break; case MSR_IA32_PERF_CAPABILITIES: msr->data = kvm_caps.supported_perf_cap; break; case MSR_IA32_UCODE_REV: rdmsrl_safe(msr->index, &msr->data); break; default: return static_call(kvm_x86_get_msr_feature)(msr); } return 0; } static int do_get_msr_feature(struct kvm_vcpu *vcpu, unsigned index, u64 *data) { struct kvm_msr_entry msr; int r; msr.index = index; r = kvm_get_msr_feature(&msr); if (r == KVM_MSR_RET_INVALID) { /* Unconditionally clear the output for simplicity */ *data = 0; if (kvm_msr_ignored_check(index, 0, false)) r = 0; } if (r) return r; *data = msr.data; return 0; } static bool __kvm_valid_efer(struct kvm_vcpu *vcpu, u64 efer) { if (efer & EFER_AUTOIBRS && !guest_cpuid_has(vcpu, X86_FEATURE_AUTOIBRS)) return false; if (efer & EFER_FFXSR && !guest_cpuid_has(vcpu, X86_FEATURE_FXSR_OPT)) return false; if (efer & EFER_SVME && !guest_cpuid_has(vcpu, X86_FEATURE_SVM)) return false; if (efer & (EFER_LME | EFER_LMA) && !guest_cpuid_has(vcpu, X86_FEATURE_LM)) return false; if (efer & EFER_NX && !guest_cpuid_has(vcpu, X86_FEATURE_NX)) return false; return true; } bool kvm_valid_efer(struct kvm_vcpu *vcpu, u64 efer) { if (efer & efer_reserved_bits) return false; return __kvm_valid_efer(vcpu, efer); } EXPORT_SYMBOL_GPL(kvm_valid_efer); static int set_efer(struct kvm_vcpu *vcpu, struct msr_data *msr_info) { u64 old_efer = vcpu->arch.efer; u64 efer = msr_info->data; int r; if (efer & efer_reserved_bits) return 1; if (!msr_info->host_initiated) { if (!__kvm_valid_efer(vcpu, efer)) return 1; if (is_paging(vcpu) && (vcpu->arch.efer & EFER_LME) != (efer & EFER_LME)) return 1; } efer &= ~EFER_LMA; efer |= vcpu->arch.efer & EFER_LMA; r = static_call(kvm_x86_set_efer)(vcpu, efer); if (r) { WARN_ON(r > 0); return r; } if ((efer ^ old_efer) & KVM_MMU_EFER_ROLE_BITS) kvm_mmu_reset_context(vcpu); return 0; } void kvm_enable_efer_bits(u64 mask) { efer_reserved_bits &= ~mask; } EXPORT_SYMBOL_GPL(kvm_enable_efer_bits); bool kvm_msr_allowed(struct kvm_vcpu *vcpu, u32 index, u32 type) { struct kvm_x86_msr_filter *msr_filter; struct msr_bitmap_range *ranges; struct kvm *kvm = vcpu->kvm; bool allowed; int idx; u32 i; /* x2APIC MSRs do not support filtering. */ if (index >= 0x800 && index <= 0x8ff) return true; idx = srcu_read_lock(&kvm->srcu); msr_filter = srcu_dereference(kvm->arch.msr_filter, &kvm->srcu); if (!msr_filter) { allowed = true; goto out; } allowed = msr_filter->default_allow; ranges = msr_filter->ranges; for (i = 0; i < msr_filter->count; i++) { u32 start = ranges[i].base; u32 end = start + ranges[i].nmsrs; u32 flags = ranges[i].flags; unsigned long *bitmap = ranges[i].bitmap; if ((index >= start) && (index < end) && (flags & type)) { allowed = test_bit(index - start, bitmap); break; } } out: srcu_read_unlock(&kvm->srcu, idx); return allowed; } EXPORT_SYMBOL_GPL(kvm_msr_allowed); /* * Write @data into the MSR specified by @index. Select MSR specific fault * checks are bypassed if @host_initiated is %true. * Returns 0 on success, non-0 otherwise. * Assumes vcpu_load() was already called. */ static int __kvm_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data, bool host_initiated) { struct msr_data msr; switch (index) { case MSR_FS_BASE: case MSR_GS_BASE: case MSR_KERNEL_GS_BASE: case MSR_CSTAR: case MSR_LSTAR: if (is_noncanonical_address(data, vcpu)) return 1; break; case MSR_IA32_SYSENTER_EIP: case MSR_IA32_SYSENTER_ESP: /* * IA32_SYSENTER_ESP and IA32_SYSENTER_EIP cause #GP if * non-canonical address is written on Intel but not on * AMD (which ignores the top 32-bits, because it does * not implement 64-bit SYSENTER). * * 64-bit code should hence be able to write a non-canonical * value on AMD. Making the address canonical ensures that * vmentry does not fail on Intel after writing a non-canonical * value, and that something deterministic happens if the guest * invokes 64-bit SYSENTER. */ data = __canonical_address(data, vcpu_virt_addr_bits(vcpu)); break; case MSR_TSC_AUX: if (!kvm_is_supported_user_return_msr(MSR_TSC_AUX)) return 1; if (!host_initiated && !guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP) && !guest_cpuid_has(vcpu, X86_FEATURE_RDPID)) return 1; /* * Per Intel's SDM, bits 63:32 are reserved, but AMD's APM has * incomplete and conflicting architectural behavior. Current * AMD CPUs completely ignore bits 63:32, i.e. they aren't * reserved and always read as zeros. Enforce Intel's reserved * bits check if and only if the guest CPU is Intel, and clear * the bits in all other cases. This ensures cross-vendor * migration will provide consistent behavior for the guest. */ if (guest_cpuid_is_intel(vcpu) && (data >> 32) != 0) return 1; data = (u32)data; break; } msr.data = data; msr.index = index; msr.host_initiated = host_initiated; return static_call(kvm_x86_set_msr)(vcpu, &msr); } static int kvm_set_msr_ignored_check(struct kvm_vcpu *vcpu, u32 index, u64 data, bool host_initiated) { int ret = __kvm_set_msr(vcpu, index, data, host_initiated); if (ret == KVM_MSR_RET_INVALID) if (kvm_msr_ignored_check(index, data, true)) ret = 0; return ret; } /* * Read the MSR specified by @index into @data. Select MSR specific fault * checks are bypassed if @host_initiated is %true. * Returns 0 on success, non-0 otherwise. * Assumes vcpu_load() was already called. */ int __kvm_get_msr(struct kvm_vcpu *vcpu, u32 index, u64 *data, bool host_initiated) { struct msr_data msr; int ret; switch (index) { case MSR_TSC_AUX: if (!kvm_is_supported_user_return_msr(MSR_TSC_AUX)) return 1; if (!host_initiated && !guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP) && !guest_cpuid_has(vcpu, X86_FEATURE_RDPID)) return 1; break; } msr.index = index; msr.host_initiated = host_initiated; ret = static_call(kvm_x86_get_msr)(vcpu, &msr); if (!ret) *data = msr.data; return ret; } static int kvm_get_msr_ignored_check(struct kvm_vcpu *vcpu, u32 index, u64 *data, bool host_initiated) { int ret = __kvm_get_msr(vcpu, index, data, host_initiated); if (ret == KVM_MSR_RET_INVALID) { /* Unconditionally clear *data for simplicity */ *data = 0; if (kvm_msr_ignored_check(index, 0, false)) ret = 0; } return ret; } static int kvm_get_msr_with_filter(struct kvm_vcpu *vcpu, u32 index, u64 *data) { if (!kvm_msr_allowed(vcpu, index, KVM_MSR_FILTER_READ)) return KVM_MSR_RET_FILTERED; return kvm_get_msr_ignored_check(vcpu, index, data, false); } static int kvm_set_msr_with_filter(struct kvm_vcpu *vcpu, u32 index, u64 data) { if (!kvm_msr_allowed(vcpu, index, KVM_MSR_FILTER_WRITE)) return KVM_MSR_RET_FILTERED; return kvm_set_msr_ignored_check(vcpu, index, data, false); } int kvm_get_msr(struct kvm_vcpu *vcpu, u32 index, u64 *data) { return kvm_get_msr_ignored_check(vcpu, index, data, false); } EXPORT_SYMBOL_GPL(kvm_get_msr); int kvm_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data) { return kvm_set_msr_ignored_check(vcpu, index, data, false); } EXPORT_SYMBOL_GPL(kvm_set_msr); static void complete_userspace_rdmsr(struct kvm_vcpu *vcpu) { if (!vcpu->run->msr.error) { kvm_rax_write(vcpu, (u32)vcpu->run->msr.data); kvm_rdx_write(vcpu, vcpu->run->msr.data >> 32); } } static int complete_emulated_msr_access(struct kvm_vcpu *vcpu) { return complete_emulated_insn_gp(vcpu, vcpu->run->msr.error); } static int complete_emulated_rdmsr(struct kvm_vcpu *vcpu) { complete_userspace_rdmsr(vcpu); return complete_emulated_msr_access(vcpu); } static int complete_fast_msr_access(struct kvm_vcpu *vcpu) { return static_call(kvm_x86_complete_emulated_msr)(vcpu, vcpu->run->msr.error); } static int complete_fast_rdmsr(struct kvm_vcpu *vcpu) { complete_userspace_rdmsr(vcpu); return complete_fast_msr_access(vcpu); } static u64 kvm_msr_reason(int r) { switch (r) { case KVM_MSR_RET_INVALID: return KVM_MSR_EXIT_REASON_UNKNOWN; case KVM_MSR_RET_FILTERED: return KVM_MSR_EXIT_REASON_FILTER; default: return KVM_MSR_EXIT_REASON_INVAL; } } static int kvm_msr_user_space(struct kvm_vcpu *vcpu, u32 index, u32 exit_reason, u64 data, int (*completion)(struct kvm_vcpu *vcpu), int r) { u64 msr_reason = kvm_msr_reason(r); /* Check if the user wanted to know about this MSR fault */ if (!(vcpu->kvm->arch.user_space_msr_mask & msr_reason)) return 0; vcpu->run->exit_reason = exit_reason; vcpu->run->msr.error = 0; memset(vcpu->run->msr.pad, 0, sizeof(vcpu->run->msr.pad)); vcpu->run->msr.reason = msr_reason; vcpu->run->msr.index = index; vcpu->run->msr.data = data; vcpu->arch.complete_userspace_io = completion; return 1; } int kvm_emulate_rdmsr(struct kvm_vcpu *vcpu) { u32 ecx = kvm_rcx_read(vcpu); u64 data; int r; r = kvm_get_msr_with_filter(vcpu, ecx, &data); if (!r) { trace_kvm_msr_read(ecx, data); kvm_rax_write(vcpu, data & -1u); kvm_rdx_write(vcpu, (data >> 32) & -1u); } else { /* MSR read failed? See if we should ask user space */ if (kvm_msr_user_space(vcpu, ecx, KVM_EXIT_X86_RDMSR, 0, complete_fast_rdmsr, r)) return 0; trace_kvm_msr_read_ex(ecx); } return static_call(kvm_x86_complete_emulated_msr)(vcpu, r); } EXPORT_SYMBOL_GPL(kvm_emulate_rdmsr); int kvm_emulate_wrmsr(struct kvm_vcpu *vcpu) { u32 ecx = kvm_rcx_read(vcpu); u64 data = kvm_read_edx_eax(vcpu); int r; r = kvm_set_msr_with_filter(vcpu, ecx, data); if (!r) { trace_kvm_msr_write(ecx, data); } else { /* MSR write failed? See if we should ask user space */ if (kvm_msr_user_space(vcpu, ecx, KVM_EXIT_X86_WRMSR, data, complete_fast_msr_access, r)) return 0; /* Signal all other negative errors to userspace */ if (r < 0) return r; trace_kvm_msr_write_ex(ecx, data); } return static_call(kvm_x86_complete_emulated_msr)(vcpu, r); } EXPORT_SYMBOL_GPL(kvm_emulate_wrmsr); int kvm_emulate_as_nop(struct kvm_vcpu *vcpu) { return kvm_skip_emulated_instruction(vcpu); } int kvm_emulate_invd(struct kvm_vcpu *vcpu) { /* Treat an INVD instruction as a NOP and just skip it. */ return kvm_emulate_as_nop(vcpu); } EXPORT_SYMBOL_GPL(kvm_emulate_invd); int kvm_handle_invalid_op(struct kvm_vcpu *vcpu) { kvm_queue_exception(vcpu, UD_VECTOR); return 1; } EXPORT_SYMBOL_GPL(kvm_handle_invalid_op); static int kvm_emulate_monitor_mwait(struct kvm_vcpu *vcpu, const char *insn) { if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MWAIT_NEVER_UD_FAULTS) && !guest_cpuid_has(vcpu, X86_FEATURE_MWAIT)) return kvm_handle_invalid_op(vcpu); pr_warn_once("%s instruction emulated as NOP!\n", insn); return kvm_emulate_as_nop(vcpu); } int kvm_emulate_mwait(struct kvm_vcpu *vcpu) { return kvm_emulate_monitor_mwait(vcpu, "MWAIT"); } EXPORT_SYMBOL_GPL(kvm_emulate_mwait); int kvm_emulate_monitor(struct kvm_vcpu *vcpu) { return kvm_emulate_monitor_mwait(vcpu, "MONITOR"); } EXPORT_SYMBOL_GPL(kvm_emulate_monitor); static inline bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu) { xfer_to_guest_mode_prepare(); return vcpu->mode == EXITING_GUEST_MODE || kvm_request_pending(vcpu) || xfer_to_guest_mode_work_pending(); } /* * The fast path for frequent and performance sensitive wrmsr emulation, * i.e. the sending of IPI, sending IPI early in the VM-Exit flow reduces * the latency of virtual IPI by avoiding the expensive bits of transitioning * from guest to host, e.g. reacquiring KVM's SRCU lock. In contrast to the * other cases which must be called after interrupts are enabled on the host. */ static int handle_fastpath_set_x2apic_icr_irqoff(struct kvm_vcpu *vcpu, u64 data) { if (!lapic_in_kernel(vcpu) || !apic_x2apic_mode(vcpu->arch.apic)) return 1; if (((data & APIC_SHORT_MASK) == APIC_DEST_NOSHORT) && ((data & APIC_DEST_MASK) == APIC_DEST_PHYSICAL) && ((data & APIC_MODE_MASK) == APIC_DM_FIXED) && ((u32)(data >> 32) != X2APIC_BROADCAST)) return kvm_x2apic_icr_write(vcpu->arch.apic, data); return 1; } static int handle_fastpath_set_tscdeadline(struct kvm_vcpu *vcpu, u64 data) { if (!kvm_can_use_hv_timer(vcpu)) return 1; kvm_set_lapic_tscdeadline_msr(vcpu, data); return 0; } fastpath_t handle_fastpath_set_msr_irqoff(struct kvm_vcpu *vcpu) { u32 msr = kvm_rcx_read(vcpu); u64 data; fastpath_t ret = EXIT_FASTPATH_NONE; kvm_vcpu_srcu_read_lock(vcpu); switch (msr) { case APIC_BASE_MSR + (APIC_ICR >> 4): data = kvm_read_edx_eax(vcpu); if (!handle_fastpath_set_x2apic_icr_irqoff(vcpu, data)) { kvm_skip_emulated_instruction(vcpu); ret = EXIT_FASTPATH_EXIT_HANDLED; } break; case MSR_IA32_TSC_DEADLINE: data = kvm_read_edx_eax(vcpu); if (!handle_fastpath_set_tscdeadline(vcpu, data)) { kvm_skip_emulated_instruction(vcpu); ret = EXIT_FASTPATH_REENTER_GUEST; } break; default: break; } if (ret != EXIT_FASTPATH_NONE) trace_kvm_msr_write(msr, data); kvm_vcpu_srcu_read_unlock(vcpu); return ret; } EXPORT_SYMBOL_GPL(handle_fastpath_set_msr_irqoff); /* * Adapt set_msr() to msr_io()'s calling convention */ static int do_get_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data) { return kvm_get_msr_ignored_check(vcpu, index, data, true); } static int do_set_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data) { u64 val; /* * Disallow writes to immutable feature MSRs after KVM_RUN. KVM does * not support modifying the guest vCPU model on the fly, e.g. changing * the nVMX capabilities while L2 is running is nonsensical. Ignore * writes of the same value, e.g. to allow userspace to blindly stuff * all MSRs when emulating RESET. */ if (kvm_vcpu_has_run(vcpu) && kvm_is_immutable_feature_msr(index)) { if (do_get_msr(vcpu, index, &val) || *data != val) return -EINVAL; return 0; } return kvm_set_msr_ignored_check(vcpu, index, *data, true); } #ifdef CONFIG_X86_64 struct pvclock_clock { int vclock_mode; u64 cycle_last; u64 mask; u32 mult; u32 shift; u64 base_cycles; u64 offset; }; struct pvclock_gtod_data { seqcount_t seq; struct pvclock_clock clock; /* extract of a clocksource struct */ struct pvclock_clock raw_clock; /* extract of a clocksource struct */ ktime_t offs_boot; u64 wall_time_sec; }; static struct pvclock_gtod_data pvclock_gtod_data; static void update_pvclock_gtod(struct timekeeper *tk) { struct pvclock_gtod_data *vdata = &pvclock_gtod_data; write_seqcount_begin(&vdata->seq); /* copy pvclock gtod data */ vdata->clock.vclock_mode = tk->tkr_mono.clock->vdso_clock_mode; vdata->clock.cycle_last = tk->tkr_mono.cycle_last; vdata->clock.mask = tk->tkr_mono.mask; vdata->clock.mult = tk->tkr_mono.mult; vdata->clock.shift = tk->tkr_mono.shift; vdata->clock.base_cycles = tk->tkr_mono.xtime_nsec; vdata->clock.offset = tk->tkr_mono.base; vdata->raw_clock.vclock_mode = tk->tkr_raw.clock->vdso_clock_mode; vdata->raw_clock.cycle_last = tk->tkr_raw.cycle_last; vdata->raw_clock.mask = tk->tkr_raw.mask; vdata->raw_clock.mult = tk->tkr_raw.mult; vdata->raw_clock.shift = tk->tkr_raw.shift; vdata->raw_clock.base_cycles = tk->tkr_raw.xtime_nsec; vdata->raw_clock.offset = tk->tkr_raw.base; vdata->wall_time_sec = tk->xtime_sec; vdata->offs_boot = tk->offs_boot; write_seqcount_end(&vdata->seq); } static s64 get_kvmclock_base_ns(void) { /* Count up from boot time, but with the frequency of the raw clock. */ return ktime_to_ns(ktime_add(ktime_get_raw(), pvclock_gtod_data.offs_boot)); } #else static s64 get_kvmclock_base_ns(void) { /* Master clock not used, so we can just use CLOCK_BOOTTIME. */ return ktime_get_boottime_ns(); } #endif static void kvm_write_wall_clock(struct kvm *kvm, gpa_t wall_clock, int sec_hi_ofs) { int version; int r; struct pvclock_wall_clock wc; u32 wc_sec_hi; u64 wall_nsec; if (!wall_clock) return; r = kvm_read_guest(kvm, wall_clock, &version, sizeof(version)); if (r) return; if (version & 1) ++version; /* first time write, random junk */ ++version; if (kvm_write_guest(kvm, wall_clock, &version, sizeof(version))) return; wall_nsec = kvm_get_wall_clock_epoch(kvm); wc.nsec = do_div(wall_nsec, NSEC_PER_SEC); wc.sec = (u32)wall_nsec; /* overflow in 2106 guest time */ wc.version = version; kvm_write_guest(kvm, wall_clock, &wc, sizeof(wc)); if (sec_hi_ofs) { wc_sec_hi = wall_nsec >> 32; kvm_write_guest(kvm, wall_clock + sec_hi_ofs, &wc_sec_hi, sizeof(wc_sec_hi)); } version++; kvm_write_guest(kvm, wall_clock, &version, sizeof(version)); } static void kvm_write_system_time(struct kvm_vcpu *vcpu, gpa_t system_time, bool old_msr, bool host_initiated) { struct kvm_arch *ka = &vcpu->kvm->arch; if (vcpu->vcpu_id == 0 && !host_initiated) { if (ka->boot_vcpu_runs_old_kvmclock != old_msr) kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu); ka->boot_vcpu_runs_old_kvmclock = old_msr; } vcpu->arch.time = system_time; kvm_make_request(KVM_REQ_GLOBAL_CLOCK_UPDATE, vcpu); /* we verify if the enable bit is set... */ if (system_time & 1) kvm_gpc_activate(&vcpu->arch.pv_time, system_time & ~1ULL, sizeof(struct pvclock_vcpu_time_info)); else kvm_gpc_deactivate(&vcpu->arch.pv_time); return; } static uint32_t div_frac(uint32_t dividend, uint32_t divisor) { do_shl32_div32(dividend, divisor); return dividend; } static void kvm_get_time_scale(uint64_t scaled_hz, uint64_t base_hz, s8 *pshift, u32 *pmultiplier) { uint64_t scaled64; int32_t shift = 0; uint64_t tps64; uint32_t tps32; tps64 = base_hz; scaled64 = scaled_hz; while (tps64 > scaled64*2 || tps64 & 0xffffffff00000000ULL) { tps64 >>= 1; shift--; } tps32 = (uint32_t)tps64; while (tps32 <= scaled64 || scaled64 & 0xffffffff00000000ULL) { if (scaled64 & 0xffffffff00000000ULL || tps32 & 0x80000000) scaled64 >>= 1; else tps32 <<= 1; shift++; } *pshift = shift; *pmultiplier = div_frac(scaled64, tps32); } #ifdef CONFIG_X86_64 static atomic_t kvm_guest_has_master_clock = ATOMIC_INIT(0); #endif static DEFINE_PER_CPU(unsigned long, cpu_tsc_khz); static unsigned long max_tsc_khz; static u32 adjust_tsc_khz(u32 khz, s32 ppm) { u64 v = (u64)khz * (1000000 + ppm); do_div(v, 1000000); return v; } static void kvm_vcpu_write_tsc_multiplier(struct kvm_vcpu *vcpu, u64 l1_multiplier); static int set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz, bool scale) { u64 ratio; /* Guest TSC same frequency as host TSC? */ if (!scale) { kvm_vcpu_write_tsc_multiplier(vcpu, kvm_caps.default_tsc_scaling_ratio); return 0; } /* TSC scaling supported? */ if (!kvm_caps.has_tsc_control) { if (user_tsc_khz > tsc_khz) { vcpu->arch.tsc_catchup = 1; vcpu->arch.tsc_always_catchup = 1; return 0; } else { pr_warn_ratelimited("user requested TSC rate below hardware speed\n"); return -1; } } /* TSC scaling required - calculate ratio */ ratio = mul_u64_u32_div(1ULL << kvm_caps.tsc_scaling_ratio_frac_bits, user_tsc_khz, tsc_khz); if (ratio == 0 || ratio >= kvm_caps.max_tsc_scaling_ratio) { pr_warn_ratelimited("Invalid TSC scaling ratio - virtual-tsc-khz=%u\n", user_tsc_khz); return -1; } kvm_vcpu_write_tsc_multiplier(vcpu, ratio); return 0; } static int kvm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz) { u32 thresh_lo, thresh_hi; int use_scaling = 0; /* tsc_khz can be zero if TSC calibration fails */ if (user_tsc_khz == 0) { /* set tsc_scaling_ratio to a safe value */ kvm_vcpu_write_tsc_multiplier(vcpu, kvm_caps.default_tsc_scaling_ratio); return -1; } /* Compute a scale to convert nanoseconds in TSC cycles */ kvm_get_time_scale(user_tsc_khz * 1000LL, NSEC_PER_SEC, &vcpu->arch.virtual_tsc_shift, &vcpu->arch.virtual_tsc_mult); vcpu->arch.virtual_tsc_khz = user_tsc_khz; /* * Compute the variation in TSC rate which is acceptable * within the range of tolerance and decide if the * rate being applied is within that bounds of the hardware * rate. If so, no scaling or compensation need be done. */ thresh_lo = adjust_tsc_khz(tsc_khz, -tsc_tolerance_ppm); thresh_hi = adjust_tsc_khz(tsc_khz, tsc_tolerance_ppm); if (user_tsc_khz < thresh_lo || user_tsc_khz > thresh_hi) { pr_debug("requested TSC rate %u falls outside tolerance [%u,%u]\n", user_tsc_khz, thresh_lo, thresh_hi); use_scaling = 1; } return set_tsc_khz(vcpu, user_tsc_khz, use_scaling); } static u64 compute_guest_tsc(struct kvm_vcpu *vcpu, s64 kernel_ns) { u64 tsc = pvclock_scale_delta(kernel_ns-vcpu->arch.this_tsc_nsec, vcpu->arch.virtual_tsc_mult, vcpu->arch.virtual_tsc_shift); tsc += vcpu->arch.this_tsc_write; return tsc; } #ifdef CONFIG_X86_64 static inline int gtod_is_based_on_tsc(int mode) { return mode == VDSO_CLOCKMODE_TSC || mode == VDSO_CLOCKMODE_HVCLOCK; } #endif static void kvm_track_tsc_matching(struct kvm_vcpu *vcpu, bool new_generation) { #ifdef CONFIG_X86_64 struct kvm_arch *ka = &vcpu->kvm->arch; struct pvclock_gtod_data *gtod = &pvclock_gtod_data; /* * To use the masterclock, the host clocksource must be based on TSC * and all vCPUs must have matching TSCs. Note, the count for matching * vCPUs doesn't include the reference vCPU, hence "+1". */ bool use_master_clock = (ka->nr_vcpus_matched_tsc + 1 == atomic_read(&vcpu->kvm->online_vcpus)) && gtod_is_based_on_tsc(gtod->clock.vclock_mode); /* * Request a masterclock update if the masterclock needs to be toggled * on/off, or when starting a new generation and the masterclock is * enabled (compute_guest_tsc() requires the masterclock snapshot to be * taken _after_ the new generation is created). */ if ((ka->use_master_clock && new_generation) || (ka->use_master_clock != use_master_clock)) kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu); trace_kvm_track_tsc(vcpu->vcpu_id, ka->nr_vcpus_matched_tsc, atomic_read(&vcpu->kvm->online_vcpus), ka->use_master_clock, gtod->clock.vclock_mode); #endif } /* * Multiply tsc by a fixed point number represented by ratio. * * The most significant 64-N bits (mult) of ratio represent the * integral part of the fixed point number; the remaining N bits * (frac) represent the fractional part, ie. ratio represents a fixed * point number (mult + frac * 2^(-N)). * * N equals to kvm_caps.tsc_scaling_ratio_frac_bits. */ static inline u64 __scale_tsc(u64 ratio, u64 tsc) { return mul_u64_u64_shr(tsc, ratio, kvm_caps.tsc_scaling_ratio_frac_bits); } u64 kvm_scale_tsc(u64 tsc, u64 ratio) { u64 _tsc = tsc; if (ratio != kvm_caps.default_tsc_scaling_ratio) _tsc = __scale_tsc(ratio, tsc); return _tsc; } static u64 kvm_compute_l1_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc) { u64 tsc; tsc = kvm_scale_tsc(rdtsc(), vcpu->arch.l1_tsc_scaling_ratio); return target_tsc - tsc; } u64 kvm_read_l1_tsc(struct kvm_vcpu *vcpu, u64 host_tsc) { return vcpu->arch.l1_tsc_offset + kvm_scale_tsc(host_tsc, vcpu->arch.l1_tsc_scaling_ratio); } EXPORT_SYMBOL_GPL(kvm_read_l1_tsc); u64 kvm_calc_nested_tsc_offset(u64 l1_offset, u64 l2_offset, u64 l2_multiplier) { u64 nested_offset; if (l2_multiplier == kvm_caps.default_tsc_scaling_ratio) nested_offset = l1_offset; else nested_offset = mul_s64_u64_shr((s64) l1_offset, l2_multiplier, kvm_caps.tsc_scaling_ratio_frac_bits); nested_offset += l2_offset; return nested_offset; } EXPORT_SYMBOL_GPL(kvm_calc_nested_tsc_offset); u64 kvm_calc_nested_tsc_multiplier(u64 l1_multiplier, u64 l2_multiplier) { if (l2_multiplier != kvm_caps.default_tsc_scaling_ratio) return mul_u64_u64_shr(l1_multiplier, l2_multiplier, kvm_caps.tsc_scaling_ratio_frac_bits); return l1_multiplier; } EXPORT_SYMBOL_GPL(kvm_calc_nested_tsc_multiplier); static void kvm_vcpu_write_tsc_offset(struct kvm_vcpu *vcpu, u64 l1_offset) { trace_kvm_write_tsc_offset(vcpu->vcpu_id, vcpu->arch.l1_tsc_offset, l1_offset); vcpu->arch.l1_tsc_offset = l1_offset; /* * If we are here because L1 chose not to trap WRMSR to TSC then * according to the spec this should set L1's TSC (as opposed to * setting L1's offset for L2). */ if (is_guest_mode(vcpu)) vcpu->arch.tsc_offset = kvm_calc_nested_tsc_offset( l1_offset, static_call(kvm_x86_get_l2_tsc_offset)(vcpu), static_call(kvm_x86_get_l2_tsc_multiplier)(vcpu)); else vcpu->arch.tsc_offset = l1_offset; static_call(kvm_x86_write_tsc_offset)(vcpu); } static void kvm_vcpu_write_tsc_multiplier(struct kvm_vcpu *vcpu, u64 l1_multiplier) { vcpu->arch.l1_tsc_scaling_ratio = l1_multiplier; /* Userspace is changing the multiplier while L2 is active */ if (is_guest_mode(vcpu)) vcpu->arch.tsc_scaling_ratio = kvm_calc_nested_tsc_multiplier( l1_multiplier, static_call(kvm_x86_get_l2_tsc_multiplier)(vcpu)); else vcpu->arch.tsc_scaling_ratio = l1_multiplier; if (kvm_caps.has_tsc_control) static_call(kvm_x86_write_tsc_multiplier)(vcpu); } static inline bool kvm_check_tsc_unstable(void) { #ifdef CONFIG_X86_64 /* * TSC is marked unstable when we're running on Hyper-V, * 'TSC page' clocksource is good. */ if (pvclock_gtod_data.clock.vclock_mode == VDSO_CLOCKMODE_HVCLOCK) return false; #endif return check_tsc_unstable(); } /* * Infers attempts to synchronize the guest's tsc from host writes. Sets the * offset for the vcpu and tracks the TSC matching generation that the vcpu * participates in. */ static void __kvm_synchronize_tsc(struct kvm_vcpu *vcpu, u64 offset, u64 tsc, u64 ns, bool matched) { struct kvm *kvm = vcpu->kvm; lockdep_assert_held(&kvm->arch.tsc_write_lock); /* * We also track th most recent recorded KHZ, write and time to * allow the matching interval to be extended at each write. */ kvm->arch.last_tsc_nsec = ns; kvm->arch.last_tsc_write = tsc; kvm->arch.last_tsc_khz = vcpu->arch.virtual_tsc_khz; kvm->arch.last_tsc_offset = offset; vcpu->arch.last_guest_tsc = tsc; kvm_vcpu_write_tsc_offset(vcpu, offset); if (!matched) { /* * We split periods of matched TSC writes into generations. * For each generation, we track the original measured * nanosecond time, offset, and write, so if TSCs are in * sync, we can match exact offset, and if not, we can match * exact software computation in compute_guest_tsc() * * These values are tracked in kvm->arch.cur_xxx variables. */ kvm->arch.cur_tsc_generation++; kvm->arch.cur_tsc_nsec = ns; kvm->arch.cur_tsc_write = tsc; kvm->arch.cur_tsc_offset = offset; kvm->arch.nr_vcpus_matched_tsc = 0; } else if (vcpu->arch.this_tsc_generation != kvm->arch.cur_tsc_generation) { kvm->arch.nr_vcpus_matched_tsc++; } /* Keep track of which generation this VCPU has synchronized to */ vcpu->arch.this_tsc_generation = kvm->arch.cur_tsc_generation; vcpu->arch.this_tsc_nsec = kvm->arch.cur_tsc_nsec; vcpu->arch.this_tsc_write = kvm->arch.cur_tsc_write; kvm_track_tsc_matching(vcpu, !matched); } static void kvm_synchronize_tsc(struct kvm_vcpu *vcpu, u64 *user_value) { u64 data = user_value ? *user_value : 0; struct kvm *kvm = vcpu->kvm; u64 offset, ns, elapsed; unsigned long flags; bool matched = false; bool synchronizing = false; raw_spin_lock_irqsave(&kvm->arch.tsc_write_lock, flags); offset = kvm_compute_l1_tsc_offset(vcpu, data); ns = get_kvmclock_base_ns(); elapsed = ns - kvm->arch.last_tsc_nsec; if (vcpu->arch.virtual_tsc_khz) { if (data == 0) { /* * Force synchronization when creating a vCPU, or when * userspace explicitly writes a zero value. */ synchronizing = true; } else if (kvm->arch.user_set_tsc) { u64 tsc_exp = kvm->arch.last_tsc_write + nsec_to_cycles(vcpu, elapsed); u64 tsc_hz = vcpu->arch.virtual_tsc_khz * 1000LL; /* * Here lies UAPI baggage: when a user-initiated TSC write has * a small delta (1 second) of virtual cycle time against the * previously set vCPU, we assume that they were intended to be * in sync and the delta was only due to the racy nature of the * legacy API. * * This trick falls down when restoring a guest which genuinely * has been running for less time than the 1 second of imprecision * which we allow for in the legacy API. In this case, the first * value written by userspace (on any vCPU) should not be subject * to this 'correction' to make it sync up with values that only * come from the kernel's default vCPU creation. Make the 1-second * slop hack only trigger if the user_set_tsc flag is already set. */ synchronizing = data < tsc_exp + tsc_hz && data + tsc_hz > tsc_exp; } } if (user_value) kvm->arch.user_set_tsc = true; /* * For a reliable TSC, we can match TSC offsets, and for an unstable * TSC, we add elapsed time in this computation. We could let the * compensation code attempt to catch up if we fall behind, but * it's better to try to match offsets from the beginning. */ if (synchronizing && vcpu->arch.virtual_tsc_khz == kvm->arch.last_tsc_khz) { if (!kvm_check_tsc_unstable()) { offset = kvm->arch.cur_tsc_offset; } else { u64 delta = nsec_to_cycles(vcpu, elapsed); data += delta; offset = kvm_compute_l1_tsc_offset(vcpu, data); } matched = true; } __kvm_synchronize_tsc(vcpu, offset, data, ns, matched); raw_spin_unlock_irqrestore(&kvm->arch.tsc_write_lock, flags); } static inline void adjust_tsc_offset_guest(struct kvm_vcpu *vcpu, s64 adjustment) { u64 tsc_offset = vcpu->arch.l1_tsc_offset; kvm_vcpu_write_tsc_offset(vcpu, tsc_offset + adjustment); } static inline void adjust_tsc_offset_host(struct kvm_vcpu *vcpu, s64 adjustment) { if (vcpu->arch.l1_tsc_scaling_ratio != kvm_caps.default_tsc_scaling_ratio) WARN_ON(adjustment < 0); adjustment = kvm_scale_tsc((u64) adjustment, vcpu->arch.l1_tsc_scaling_ratio); adjust_tsc_offset_guest(vcpu, adjustment); } #ifdef CONFIG_X86_64 static u64 read_tsc(void) { u64 ret = (u64)rdtsc_ordered(); u64 last = pvclock_gtod_data.clock.cycle_last; if (likely(ret >= last)) return ret; /* * GCC likes to generate cmov here, but this branch is extremely * predictable (it's just a function of time and the likely is * very likely) and there's a data dependence, so force GCC * to generate a branch instead. I don't barrier() because * we don't actually need a barrier, and if this function * ever gets inlined it will generate worse code. */ asm volatile (""); return last; } static inline u64 vgettsc(struct pvclock_clock *clock, u64 *tsc_timestamp, int *mode) { u64 tsc_pg_val; long v; switch (clock->vclock_mode) { case VDSO_CLOCKMODE_HVCLOCK: if (hv_read_tsc_page_tsc(hv_get_tsc_page(), tsc_timestamp, &tsc_pg_val)) { /* TSC page valid */ *mode = VDSO_CLOCKMODE_HVCLOCK; v = (tsc_pg_val - clock->cycle_last) & clock->mask; } else { /* TSC page invalid */ *mode = VDSO_CLOCKMODE_NONE; } break; case VDSO_CLOCKMODE_TSC: *mode = VDSO_CLOCKMODE_TSC; *tsc_timestamp = read_tsc(); v = (*tsc_timestamp - clock->cycle_last) & clock->mask; break; default: *mode = VDSO_CLOCKMODE_NONE; } if (*mode == VDSO_CLOCKMODE_NONE) *tsc_timestamp = v = 0; return v * clock->mult; } static int do_monotonic_raw(s64 *t, u64 *tsc_timestamp) { struct pvclock_gtod_data *gtod = &pvclock_gtod_data; unsigned long seq; int mode; u64 ns; do { seq = read_seqcount_begin(>od->seq); ns = gtod->raw_clock.base_cycles; ns += vgettsc(>od->raw_clock, tsc_timestamp, &mode); ns >>= gtod->raw_clock.shift; ns += ktime_to_ns(ktime_add(gtod->raw_clock.offset, gtod->offs_boot)); } while (unlikely(read_seqcount_retry(>od->seq, seq))); *t = ns; return mode; } static int do_realtime(struct timespec64 *ts, u64 *tsc_timestamp) { struct pvclock_gtod_data *gtod = &pvclock_gtod_data; unsigned long seq; int mode; u64 ns; do { seq = read_seqcount_begin(>od->seq); ts->tv_sec = gtod->wall_time_sec; ns = gtod->clock.base_cycles; ns += vgettsc(>od->clock, tsc_timestamp, &mode); ns >>= gtod->clock.shift; } while (unlikely(read_seqcount_retry(>od->seq, seq))); ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns); ts->tv_nsec = ns; return mode; } /* returns true if host is using TSC based clocksource */ static bool kvm_get_time_and_clockread(s64 *kernel_ns, u64 *tsc_timestamp) { /* checked again under seqlock below */ if (!gtod_is_based_on_tsc(pvclock_gtod_data.clock.vclock_mode)) return false; return gtod_is_based_on_tsc(do_monotonic_raw(kernel_ns, tsc_timestamp)); } /* returns true if host is using TSC based clocksource */ static bool kvm_get_walltime_and_clockread(struct timespec64 *ts, u64 *tsc_timestamp) { /* checked again under seqlock below */ if (!gtod_is_based_on_tsc(pvclock_gtod_data.clock.vclock_mode)) return false; return gtod_is_based_on_tsc(do_realtime(ts, tsc_timestamp)); } #endif /* * * Assuming a stable TSC across physical CPUS, and a stable TSC * across virtual CPUs, the following condition is possible. * Each numbered line represents an event visible to both * CPUs at the next numbered event. * * "timespecX" represents host monotonic time. "tscX" represents * RDTSC value. * * VCPU0 on CPU0 | VCPU1 on CPU1 * * 1. read timespec0,tsc0 * 2. | timespec1 = timespec0 + N * | tsc1 = tsc0 + M * 3. transition to guest | transition to guest * 4. ret0 = timespec0 + (rdtsc - tsc0) | * 5. | ret1 = timespec1 + (rdtsc - tsc1) * | ret1 = timespec0 + N + (rdtsc - (tsc0 + M)) * * Since ret0 update is visible to VCPU1 at time 5, to obey monotonicity: * * - ret0 < ret1 * - timespec0 + (rdtsc - tsc0) < timespec0 + N + (rdtsc - (tsc0 + M)) * ... * - 0 < N - M => M < N * * That is, when timespec0 != timespec1, M < N. Unfortunately that is not * always the case (the difference between two distinct xtime instances * might be smaller then the difference between corresponding TSC reads, * when updating guest vcpus pvclock areas). * * To avoid that problem, do not allow visibility of distinct * system_timestamp/tsc_timestamp values simultaneously: use a master * copy of host monotonic time values. Update that master copy * in lockstep. * * Rely on synchronization of host TSCs and guest TSCs for monotonicity. * */ static void pvclock_update_vm_gtod_copy(struct kvm *kvm) { #ifdef CONFIG_X86_64 struct kvm_arch *ka = &kvm->arch; int vclock_mode; bool host_tsc_clocksource, vcpus_matched; lockdep_assert_held(&kvm->arch.tsc_write_lock); vcpus_matched = (ka->nr_vcpus_matched_tsc + 1 == atomic_read(&kvm->online_vcpus)); /* * If the host uses TSC clock, then passthrough TSC as stable * to the guest. */ host_tsc_clocksource = kvm_get_time_and_clockread( &ka->master_kernel_ns, &ka->master_cycle_now); ka->use_master_clock = host_tsc_clocksource && vcpus_matched && !ka->backwards_tsc_observed && !ka->boot_vcpu_runs_old_kvmclock; if (ka->use_master_clock) atomic_set(&kvm_guest_has_master_clock, 1); vclock_mode = pvclock_gtod_data.clock.vclock_mode; trace_kvm_update_master_clock(ka->use_master_clock, vclock_mode, vcpus_matched); #endif } static void kvm_make_mclock_inprogress_request(struct kvm *kvm) { kvm_make_all_cpus_request(kvm, KVM_REQ_MCLOCK_INPROGRESS); } static void __kvm_start_pvclock_update(struct kvm *kvm) { raw_spin_lock_irq(&kvm->arch.tsc_write_lock); write_seqcount_begin(&kvm->arch.pvclock_sc); } static void kvm_start_pvclock_update(struct kvm *kvm) { kvm_make_mclock_inprogress_request(kvm); /* no guest entries from this point */ __kvm_start_pvclock_update(kvm); } static void kvm_end_pvclock_update(struct kvm *kvm) { struct kvm_arch *ka = &kvm->arch; struct kvm_vcpu *vcpu; unsigned long i; write_seqcount_end(&ka->pvclock_sc); raw_spin_unlock_irq(&ka->tsc_write_lock); kvm_for_each_vcpu(i, vcpu, kvm) kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu); /* guest entries allowed */ kvm_for_each_vcpu(i, vcpu, kvm) kvm_clear_request(KVM_REQ_MCLOCK_INPROGRESS, vcpu); } static void kvm_update_masterclock(struct kvm *kvm) { kvm_hv_request_tsc_page_update(kvm); kvm_start_pvclock_update(kvm); pvclock_update_vm_gtod_copy(kvm); kvm_end_pvclock_update(kvm); } /* * Use the kernel's tsc_khz directly if the TSC is constant, otherwise use KVM's * per-CPU value (which may be zero if a CPU is going offline). Note, tsc_khz * can change during boot even if the TSC is constant, as it's possible for KVM * to be loaded before TSC calibration completes. Ideally, KVM would get a * notification when calibration completes, but practically speaking calibration * will complete before userspace is alive enough to create VMs. */ static unsigned long get_cpu_tsc_khz(void) { if (static_cpu_has(X86_FEATURE_CONSTANT_TSC)) return tsc_khz; else return __this_cpu_read(cpu_tsc_khz); } /* Called within read_seqcount_begin/retry for kvm->pvclock_sc. */ static void __get_kvmclock(struct kvm *kvm, struct kvm_clock_data *data) { struct kvm_arch *ka = &kvm->arch; struct pvclock_vcpu_time_info hv_clock; /* both __this_cpu_read() and rdtsc() should be on the same cpu */ get_cpu(); data->flags = 0; if (ka->use_master_clock && (static_cpu_has(X86_FEATURE_CONSTANT_TSC) || __this_cpu_read(cpu_tsc_khz))) { #ifdef CONFIG_X86_64 struct timespec64 ts; if (kvm_get_walltime_and_clockread(&ts, &data->host_tsc)) { data->realtime = ts.tv_nsec + NSEC_PER_SEC * ts.tv_sec; data->flags |= KVM_CLOCK_REALTIME | KVM_CLOCK_HOST_TSC; } else #endif data->host_tsc = rdtsc(); data->flags |= KVM_CLOCK_TSC_STABLE; hv_clock.tsc_timestamp = ka->master_cycle_now; hv_clock.system_time = ka->master_kernel_ns + ka->kvmclock_offset; kvm_get_time_scale(NSEC_PER_SEC, get_cpu_tsc_khz() * 1000LL, &hv_clock.tsc_shift, &hv_clock.tsc_to_system_mul); data->clock = __pvclock_read_cycles(&hv_clock, data->host_tsc); } else { data->clock = get_kvmclock_base_ns() + ka->kvmclock_offset; } put_cpu(); } static void get_kvmclock(struct kvm *kvm, struct kvm_clock_data *data) { struct kvm_arch *ka = &kvm->arch; unsigned seq; do { seq = read_seqcount_begin(&ka->pvclock_sc); __get_kvmclock(kvm, data); } while (read_seqcount_retry(&ka->pvclock_sc, seq)); } u64 get_kvmclock_ns(struct kvm *kvm) { struct kvm_clock_data data; get_kvmclock(kvm, &data); return data.clock; } static void kvm_setup_guest_pvclock(struct kvm_vcpu *v, struct gfn_to_pfn_cache *gpc, unsigned int offset, bool force_tsc_unstable) { struct kvm_vcpu_arch *vcpu = &v->arch; struct pvclock_vcpu_time_info *guest_hv_clock; unsigned long flags; read_lock_irqsave(&gpc->lock, flags); while (!kvm_gpc_check(gpc, offset + sizeof(*guest_hv_clock))) { read_unlock_irqrestore(&gpc->lock, flags); if (kvm_gpc_refresh(gpc, offset + sizeof(*guest_hv_clock))) return; read_lock_irqsave(&gpc->lock, flags); } guest_hv_clock = (void *)(gpc->khva + offset); /* * This VCPU is paused, but it's legal for a guest to read another * VCPU's kvmclock, so we really have to follow the specification where * it says that version is odd if data is being modified, and even after * it is consistent. */ guest_hv_clock->version = vcpu->hv_clock.version = (guest_hv_clock->version + 1) | 1; smp_wmb(); /* retain PVCLOCK_GUEST_STOPPED if set in guest copy */ vcpu->hv_clock.flags |= (guest_hv_clock->flags & PVCLOCK_GUEST_STOPPED); if (vcpu->pvclock_set_guest_stopped_request) { vcpu->hv_clock.flags |= PVCLOCK_GUEST_STOPPED; vcpu->pvclock_set_guest_stopped_request = false; } memcpy(guest_hv_clock, &vcpu->hv_clock, sizeof(*guest_hv_clock)); if (force_tsc_unstable) guest_hv_clock->flags &= ~PVCLOCK_TSC_STABLE_BIT; smp_wmb(); guest_hv_clock->version = ++vcpu->hv_clock.version; mark_page_dirty_in_slot(v->kvm, gpc->memslot, gpc->gpa >> PAGE_SHIFT); read_unlock_irqrestore(&gpc->lock, flags); trace_kvm_pvclock_update(v->vcpu_id, &vcpu->hv_clock); } static int kvm_guest_time_update(struct kvm_vcpu *v) { unsigned long flags, tgt_tsc_khz; unsigned seq; struct kvm_vcpu_arch *vcpu = &v->arch; struct kvm_arch *ka = &v->kvm->arch; s64 kernel_ns; u64 tsc_timestamp, host_tsc; u8 pvclock_flags; bool use_master_clock; #ifdef CONFIG_KVM_XEN /* * For Xen guests we may need to override PVCLOCK_TSC_STABLE_BIT as unless * explicitly told to use TSC as its clocksource Xen will not set this bit. * This default behaviour led to bugs in some guest kernels which cause * problems if they observe PVCLOCK_TSC_STABLE_BIT in the pvclock flags. */ bool xen_pvclock_tsc_unstable = ka->xen_hvm_config.flags & KVM_XEN_HVM_CONFIG_PVCLOCK_TSC_UNSTABLE; #endif kernel_ns = 0; host_tsc = 0; /* * If the host uses TSC clock, then passthrough TSC as stable * to the guest. */ do { seq = read_seqcount_begin(&ka->pvclock_sc); use_master_clock = ka->use_master_clock; if (use_master_clock) { host_tsc = ka->master_cycle_now; kernel_ns = ka->master_kernel_ns; } } while (read_seqcount_retry(&ka->pvclock_sc, seq)); /* Keep irq disabled to prevent changes to the clock */ local_irq_save(flags); tgt_tsc_khz = get_cpu_tsc_khz(); if (unlikely(tgt_tsc_khz == 0)) { local_irq_restore(flags); kvm_make_request(KVM_REQ_CLOCK_UPDATE, v); return 1; } if (!use_master_clock) { host_tsc = rdtsc(); kernel_ns = get_kvmclock_base_ns(); } tsc_timestamp = kvm_read_l1_tsc(v, host_tsc); /* * We may have to catch up the TSC to match elapsed wall clock * time for two reasons, even if kvmclock is used. * 1) CPU could have been running below the maximum TSC rate * 2) Broken TSC compensation resets the base at each VCPU * entry to avoid unknown leaps of TSC even when running * again on the same CPU. This may cause apparent elapsed * time to disappear, and the guest to stand still or run * very slowly. */ if (vcpu->tsc_catchup) { u64 tsc = compute_guest_tsc(v, kernel_ns); if (tsc > tsc_timestamp) { adjust_tsc_offset_guest(v, tsc - tsc_timestamp); tsc_timestamp = tsc; } } local_irq_restore(flags); /* With all the info we got, fill in the values */ if (kvm_caps.has_tsc_control) tgt_tsc_khz = kvm_scale_tsc(tgt_tsc_khz, v->arch.l1_tsc_scaling_ratio); if (unlikely(vcpu->hw_tsc_khz != tgt_tsc_khz)) { kvm_get_time_scale(NSEC_PER_SEC, tgt_tsc_khz * 1000LL, &vcpu->hv_clock.tsc_shift, &vcpu->hv_clock.tsc_to_system_mul); vcpu->hw_tsc_khz = tgt_tsc_khz; kvm_xen_update_tsc_info(v); } vcpu->hv_clock.tsc_timestamp = tsc_timestamp; vcpu->hv_clock.system_time = kernel_ns + v->kvm->arch.kvmclock_offset; vcpu->last_guest_tsc = tsc_timestamp; /* If the host uses TSC clocksource, then it is stable */ pvclock_flags = 0; if (use_master_clock) pvclock_flags |= PVCLOCK_TSC_STABLE_BIT; vcpu->hv_clock.flags = pvclock_flags; if (vcpu->pv_time.active) kvm_setup_guest_pvclock(v, &vcpu->pv_time, 0, false); #ifdef CONFIG_KVM_XEN if (vcpu->xen.vcpu_info_cache.active) kvm_setup_guest_pvclock(v, &vcpu->xen.vcpu_info_cache, offsetof(struct compat_vcpu_info, time), xen_pvclock_tsc_unstable); if (vcpu->xen.vcpu_time_info_cache.active) kvm_setup_guest_pvclock(v, &vcpu->xen.vcpu_time_info_cache, 0, xen_pvclock_tsc_unstable); #endif kvm_hv_setup_tsc_page(v->kvm, &vcpu->hv_clock); return 0; } /* * The pvclock_wall_clock ABI tells the guest the wall clock time at * which it started (i.e. its epoch, when its kvmclock was zero). * * In fact those clocks are subtly different; wall clock frequency is * adjusted by NTP and has leap seconds, while the kvmclock is a * simple function of the TSC without any such adjustment. * * Perhaps the ABI should have exposed CLOCK_TAI and a ratio between * that and kvmclock, but even that would be subject to change over * time. * * Attempt to calculate the epoch at a given moment using the *same* * TSC reading via kvm_get_walltime_and_clockread() to obtain both * wallclock and kvmclock times, and subtracting one from the other. * * Fall back to using their values at slightly different moments by * calling ktime_get_real_ns() and get_kvmclock_ns() separately. */ uint64_t kvm_get_wall_clock_epoch(struct kvm *kvm) { #ifdef CONFIG_X86_64 struct pvclock_vcpu_time_info hv_clock; struct kvm_arch *ka = &kvm->arch; unsigned long seq, local_tsc_khz; struct timespec64 ts; uint64_t host_tsc; do { seq = read_seqcount_begin(&ka->pvclock_sc); local_tsc_khz = 0; if (!ka->use_master_clock) break; /* * The TSC read and the call to get_cpu_tsc_khz() must happen * on the same CPU. */ get_cpu(); local_tsc_khz = get_cpu_tsc_khz(); if (local_tsc_khz && !kvm_get_walltime_and_clockread(&ts, &host_tsc)) local_tsc_khz = 0; /* Fall back to old method */ put_cpu(); /* * These values must be snapshotted within the seqcount loop. * After that, it's just mathematics which can happen on any * CPU at any time. */ hv_clock.tsc_timestamp = ka->master_cycle_now; hv_clock.system_time = ka->master_kernel_ns + ka->kvmclock_offset; } while (read_seqcount_retry(&ka->pvclock_sc, seq)); /* * If the conditions were right, and obtaining the wallclock+TSC was * successful, calculate the KVM clock at the corresponding time and * subtract one from the other to get the guest's epoch in nanoseconds * since 1970-01-01. */ if (local_tsc_khz) { kvm_get_time_scale(NSEC_PER_SEC, local_tsc_khz * NSEC_PER_USEC, &hv_clock.tsc_shift, &hv_clock.tsc_to_system_mul); return ts.tv_nsec + NSEC_PER_SEC * ts.tv_sec - __pvclock_read_cycles(&hv_clock, host_tsc); } #endif return ktime_get_real_ns() - get_kvmclock_ns(kvm); } /* * kvmclock updates which are isolated to a given vcpu, such as * vcpu->cpu migration, should not allow system_timestamp from * the rest of the vcpus to remain static. Otherwise ntp frequency * correction applies to one vcpu's system_timestamp but not * the others. * * So in those cases, request a kvmclock update for all vcpus. * We need to rate-limit these requests though, as they can * considerably slow guests that have a large number of vcpus. * The time for a remote vcpu to update its kvmclock is bound * by the delay we use to rate-limit the updates. */ #define KVMCLOCK_UPDATE_DELAY msecs_to_jiffies(100) static void kvmclock_update_fn(struct work_struct *work) { unsigned long i; struct delayed_work *dwork = to_delayed_work(work); struct kvm_arch *ka = container_of(dwork, struct kvm_arch, kvmclock_update_work); struct kvm *kvm = container_of(ka, struct kvm, arch); struct kvm_vcpu *vcpu; kvm_for_each_vcpu(i, vcpu, kvm) { kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu); kvm_vcpu_kick(vcpu); } } static void kvm_gen_kvmclock_update(struct kvm_vcpu *v) { struct kvm *kvm = v->kvm; kvm_make_request(KVM_REQ_CLOCK_UPDATE, v); schedule_delayed_work(&kvm->arch.kvmclock_update_work, KVMCLOCK_UPDATE_DELAY); } #define KVMCLOCK_SYNC_PERIOD (300 * HZ) static void kvmclock_sync_fn(struct work_struct *work) { struct delayed_work *dwork = to_delayed_work(work); struct kvm_arch *ka = container_of(dwork, struct kvm_arch, kvmclock_sync_work); struct kvm *kvm = container_of(ka, struct kvm, arch); schedule_delayed_work(&kvm->arch.kvmclock_update_work, 0); schedule_delayed_work(&kvm->arch.kvmclock_sync_work, KVMCLOCK_SYNC_PERIOD); } /* These helpers are safe iff @msr is known to be an MCx bank MSR. */ static bool is_mci_control_msr(u32 msr) { return (msr & 3) == 0; } static bool is_mci_status_msr(u32 msr) { return (msr & 3) == 1; } /* * On AMD, HWCR[McStatusWrEn] controls whether setting MCi_STATUS results in #GP. */ static bool can_set_mci_status(struct kvm_vcpu *vcpu) { /* McStatusWrEn enabled? */ if (guest_cpuid_is_amd_or_hygon(vcpu)) return !!(vcpu->arch.msr_hwcr & BIT_ULL(18)); return false; } static int set_msr_mce(struct kvm_vcpu *vcpu, struct msr_data *msr_info) { u64 mcg_cap = vcpu->arch.mcg_cap; unsigned bank_num = mcg_cap & 0xff; u32 msr = msr_info->index; u64 data = msr_info->data; u32 offset, last_msr; switch (msr) { case MSR_IA32_MCG_STATUS: vcpu->arch.mcg_status = data; break; case MSR_IA32_MCG_CTL: if (!(mcg_cap & MCG_CTL_P) && (data || !msr_info->host_initiated)) return 1; if (data != 0 && data != ~(u64)0) return 1; vcpu->arch.mcg_ctl = data; break; case MSR_IA32_MC0_CTL2 ... MSR_IA32_MCx_CTL2(KVM_MAX_MCE_BANKS) - 1: last_msr = MSR_IA32_MCx_CTL2(bank_num) - 1; if (msr > last_msr) return 1; if (!(mcg_cap & MCG_CMCI_P) && (data || !msr_info->host_initiated)) return 1; /* An attempt to write a 1 to a reserved bit raises #GP */ if (data & ~(MCI_CTL2_CMCI_EN | MCI_CTL2_CMCI_THRESHOLD_MASK)) return 1; offset = array_index_nospec(msr - MSR_IA32_MC0_CTL2, last_msr + 1 - MSR_IA32_MC0_CTL2); vcpu->arch.mci_ctl2_banks[offset] = data; break; case MSR_IA32_MC0_CTL ... MSR_IA32_MCx_CTL(KVM_MAX_MCE_BANKS) - 1: last_msr = MSR_IA32_MCx_CTL(bank_num) - 1; if (msr > last_msr) return 1; /* * Only 0 or all 1s can be written to IA32_MCi_CTL, all other * values are architecturally undefined. But, some Linux * kernels clear bit 10 in bank 4 to workaround a BIOS/GART TLB * issue on AMD K8s, allow bit 10 to be clear when setting all * other bits in order to avoid an uncaught #GP in the guest. * * UNIXWARE clears bit 0 of MC1_CTL to ignore correctable, * single-bit ECC data errors. */ if (is_mci_control_msr(msr) && data != 0 && (data | (1 << 10) | 1) != ~(u64)0) return 1; /* * All CPUs allow writing 0 to MCi_STATUS MSRs to clear the MSR. * AMD-based CPUs allow non-zero values, but if and only if * HWCR[McStatusWrEn] is set. */ if (!msr_info->host_initiated && is_mci_status_msr(msr) && data != 0 && !can_set_mci_status(vcpu)) return 1; offset = array_index_nospec(msr - MSR_IA32_MC0_CTL, last_msr + 1 - MSR_IA32_MC0_CTL); vcpu->arch.mce_banks[offset] = data; break; default: return 1; } return 0; } static inline bool kvm_pv_async_pf_enabled(struct kvm_vcpu *vcpu) { u64 mask = KVM_ASYNC_PF_ENABLED | KVM_ASYNC_PF_DELIVERY_AS_INT; return (vcpu->arch.apf.msr_en_val & mask) == mask; } static int kvm_pv_enable_async_pf(struct kvm_vcpu *vcpu, u64 data) { gpa_t gpa = data & ~0x3f; /* Bits 4:5 are reserved, Should be zero */ if (data & 0x30) return 1; if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_VMEXIT) && (data & KVM_ASYNC_PF_DELIVERY_AS_PF_VMEXIT)) return 1; if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT) && (data & KVM_ASYNC_PF_DELIVERY_AS_INT)) return 1; if (!lapic_in_kernel(vcpu)) return data ? 1 : 0; vcpu->arch.apf.msr_en_val = data; if (!kvm_pv_async_pf_enabled(vcpu)) { kvm_clear_async_pf_completion_queue(vcpu); kvm_async_pf_hash_reset(vcpu); return 0; } if (kvm_gfn_to_hva_cache_init(vcpu->kvm, &vcpu->arch.apf.data, gpa, sizeof(u64))) return 1; vcpu->arch.apf.send_user_only = !(data & KVM_ASYNC_PF_SEND_ALWAYS); vcpu->arch.apf.delivery_as_pf_vmexit = data & KVM_ASYNC_PF_DELIVERY_AS_PF_VMEXIT; kvm_async_pf_wakeup_all(vcpu); return 0; } static int kvm_pv_enable_async_pf_int(struct kvm_vcpu *vcpu, u64 data) { /* Bits 8-63 are reserved */ if (data >> 8) return 1; if (!lapic_in_kernel(vcpu)) return 1; vcpu->arch.apf.msr_int_val = data; vcpu->arch.apf.vec = data & KVM_ASYNC_PF_VEC_MASK; return 0; } static void kvmclock_reset(struct kvm_vcpu *vcpu) { kvm_gpc_deactivate(&vcpu->arch.pv_time); vcpu->arch.time = 0; } static void kvm_vcpu_flush_tlb_all(struct kvm_vcpu *vcpu) { ++vcpu->stat.tlb_flush; static_call(kvm_x86_flush_tlb_all)(vcpu); /* Flushing all ASIDs flushes the current ASID... */ kvm_clear_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu); } static void kvm_vcpu_flush_tlb_guest(struct kvm_vcpu *vcpu) { ++vcpu->stat.tlb_flush; if (!tdp_enabled) { /* * A TLB flush on behalf of the guest is equivalent to * INVPCID(all), toggling CR4.PGE, etc., which requires * a forced sync of the shadow page tables. Ensure all the * roots are synced and the guest TLB in hardware is clean. */ kvm_mmu_sync_roots(vcpu); kvm_mmu_sync_prev_roots(vcpu); } static_call(kvm_x86_flush_tlb_guest)(vcpu); /* * Flushing all "guest" TLB is always a superset of Hyper-V's fine * grained flushing. */ kvm_hv_vcpu_purge_flush_tlb(vcpu); } static inline void kvm_vcpu_flush_tlb_current(struct kvm_vcpu *vcpu) { ++vcpu->stat.tlb_flush; static_call(kvm_x86_flush_tlb_current)(vcpu); } /* * Service "local" TLB flush requests, which are specific to the current MMU * context. In addition to the generic event handling in vcpu_enter_guest(), * TLB flushes that are targeted at an MMU context also need to be serviced * prior before nested VM-Enter/VM-Exit. */ void kvm_service_local_tlb_flush_requests(struct kvm_vcpu *vcpu) { if (kvm_check_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu)) kvm_vcpu_flush_tlb_current(vcpu); if (kvm_check_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu)) kvm_vcpu_flush_tlb_guest(vcpu); } EXPORT_SYMBOL_GPL(kvm_service_local_tlb_flush_requests); static void record_steal_time(struct kvm_vcpu *vcpu) { struct gfn_to_hva_cache *ghc = &vcpu->arch.st.cache; struct kvm_steal_time __user *st; struct kvm_memslots *slots; gpa_t gpa = vcpu->arch.st.msr_val & KVM_STEAL_VALID_BITS; u64 steal; u32 version; if (kvm_xen_msr_enabled(vcpu->kvm)) { kvm_xen_runstate_set_running(vcpu); return; } if (!(vcpu->arch.st.msr_val & KVM_MSR_ENABLED)) return; if (WARN_ON_ONCE(current->mm != vcpu->kvm->mm)) return; slots = kvm_memslots(vcpu->kvm); if (unlikely(slots->generation != ghc->generation || gpa != ghc->gpa || kvm_is_error_hva(ghc->hva) || !ghc->memslot)) { /* We rely on the fact that it fits in a single page. */ BUILD_BUG_ON((sizeof(*st) - 1) & KVM_STEAL_VALID_BITS); if (kvm_gfn_to_hva_cache_init(vcpu->kvm, ghc, gpa, sizeof(*st)) || kvm_is_error_hva(ghc->hva) || !ghc->memslot) return; } st = (struct kvm_steal_time __user *)ghc->hva; /* * Doing a TLB flush here, on the guest's behalf, can avoid * expensive IPIs. */ if (guest_pv_has(vcpu, KVM_FEATURE_PV_TLB_FLUSH)) { u8 st_preempted = 0; int err = -EFAULT; if (!user_access_begin(st, sizeof(*st))) return; asm volatile("1: xchgb %0, %2\n" "xor %1, %1\n" "2:\n" _ASM_EXTABLE_UA(1b, 2b) : "+q" (st_preempted), "+&r" (err), "+m" (st->preempted)); if (err) goto out; user_access_end(); vcpu->arch.st.preempted = 0; trace_kvm_pv_tlb_flush(vcpu->vcpu_id, st_preempted & KVM_VCPU_FLUSH_TLB); if (st_preempted & KVM_VCPU_FLUSH_TLB) kvm_vcpu_flush_tlb_guest(vcpu); if (!user_access_begin(st, sizeof(*st))) goto dirty; } else { if (!user_access_begin(st, sizeof(*st))) return; unsafe_put_user(0, &st->preempted, out); vcpu->arch.st.preempted = 0; } unsafe_get_user(version, &st->version, out); if (version & 1) version += 1; /* first time write, random junk */ version += 1; unsafe_put_user(version, &st->version, out); smp_wmb(); unsafe_get_user(steal, &st->steal, out); steal += current->sched_info.run_delay - vcpu->arch.st.last_steal; vcpu->arch.st.last_steal = current->sched_info.run_delay; unsafe_put_user(steal, &st->steal, out); version += 1; unsafe_put_user(version, &st->version, out); out: user_access_end(); dirty: mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa)); } static bool kvm_is_msr_to_save(u32 msr_index) { unsigned int i; for (i = 0; i < num_msrs_to_save; i++) { if (msrs_to_save[i] == msr_index) return true; } return false; } int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) { u32 msr = msr_info->index; u64 data = msr_info->data; if (msr && msr == vcpu->kvm->arch.xen_hvm_config.msr) return kvm_xen_write_hypercall_page(vcpu, data); switch (msr) { case MSR_AMD64_NB_CFG: case MSR_IA32_UCODE_WRITE: case MSR_VM_HSAVE_PA: case MSR_AMD64_PATCH_LOADER: case MSR_AMD64_BU_CFG2: case MSR_AMD64_DC_CFG: case MSR_AMD64_TW_CFG: case MSR_F15H_EX_CFG: break; case MSR_IA32_UCODE_REV: if (msr_info->host_initiated) vcpu->arch.microcode_version = data; break; case MSR_IA32_ARCH_CAPABILITIES: if (!msr_info->host_initiated) return 1; vcpu->arch.arch_capabilities = data; break; case MSR_IA32_PERF_CAPABILITIES: if (!msr_info->host_initiated) return 1; if (data & ~kvm_caps.supported_perf_cap) return 1; /* * Note, this is not just a performance optimization! KVM * disallows changing feature MSRs after the vCPU has run; PMU * refresh will bug the VM if called after the vCPU has run. */ if (vcpu->arch.perf_capabilities == data) break; vcpu->arch.perf_capabilities = data; kvm_pmu_refresh(vcpu); break; case MSR_IA32_PRED_CMD: { u64 reserved_bits = ~(PRED_CMD_IBPB | PRED_CMD_SBPB); if (!msr_info->host_initiated) { if ((!guest_has_pred_cmd_msr(vcpu))) return 1; if (!guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL) && !guest_cpuid_has(vcpu, X86_FEATURE_AMD_IBPB)) reserved_bits |= PRED_CMD_IBPB; if (!guest_cpuid_has(vcpu, X86_FEATURE_SBPB)) reserved_bits |= PRED_CMD_SBPB; } if (!boot_cpu_has(X86_FEATURE_IBPB)) reserved_bits |= PRED_CMD_IBPB; if (!boot_cpu_has(X86_FEATURE_SBPB)) reserved_bits |= PRED_CMD_SBPB; if (data & reserved_bits) return 1; if (!data) break; wrmsrl(MSR_IA32_PRED_CMD, data); break; } case MSR_IA32_FLUSH_CMD: if (!msr_info->host_initiated && !guest_cpuid_has(vcpu, X86_FEATURE_FLUSH_L1D)) return 1; if (!boot_cpu_has(X86_FEATURE_FLUSH_L1D) || (data & ~L1D_FLUSH)) return 1; if (!data) break; wrmsrl(MSR_IA32_FLUSH_CMD, L1D_FLUSH); break; case MSR_EFER: return set_efer(vcpu, msr_info); case MSR_K7_HWCR: data &= ~(u64)0x40; /* ignore flush filter disable */ data &= ~(u64)0x100; /* ignore ignne emulation enable */ data &= ~(u64)0x8; /* ignore TLB cache disable */ /* * Allow McStatusWrEn and TscFreqSel. (Linux guests from v3.2 * through at least v6.6 whine if TscFreqSel is clear, * depending on F/M/S. */ if (data & ~(BIT_ULL(18) | BIT_ULL(24))) { kvm_pr_unimpl_wrmsr(vcpu, msr, data); return 1; } vcpu->arch.msr_hwcr = data; break; case MSR_FAM10H_MMIO_CONF_BASE: if (data != 0) { kvm_pr_unimpl_wrmsr(vcpu, msr, data); return 1; } break; case MSR_IA32_CR_PAT: if (!kvm_pat_valid(data)) return 1; vcpu->arch.pat = data; break; case MTRRphysBase_MSR(0) ... MSR_MTRRfix4K_F8000: case MSR_MTRRdefType: return kvm_mtrr_set_msr(vcpu, msr, data); case MSR_IA32_APICBASE: return kvm_set_apic_base(vcpu, msr_info); case APIC_BASE_MSR ... APIC_BASE_MSR + 0xff: return kvm_x2apic_msr_write(vcpu, msr, data); case MSR_IA32_TSC_DEADLINE: kvm_set_lapic_tscdeadline_msr(vcpu, data); break; case MSR_IA32_TSC_ADJUST: if (guest_cpuid_has(vcpu, X86_FEATURE_TSC_ADJUST)) { if (!msr_info->host_initiated) { s64 adj = data - vcpu->arch.ia32_tsc_adjust_msr; adjust_tsc_offset_guest(vcpu, adj); /* Before back to guest, tsc_timestamp must be adjusted * as well, otherwise guest's percpu pvclock time could jump. */ kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu); } vcpu->arch.ia32_tsc_adjust_msr = data; } break; case MSR_IA32_MISC_ENABLE: { u64 old_val = vcpu->arch.ia32_misc_enable_msr; if (!msr_info->host_initiated) { /* RO bits */ if ((old_val ^ data) & MSR_IA32_MISC_ENABLE_PMU_RO_MASK) return 1; /* R bits, i.e. writes are ignored, but don't fault. */ data = data & ~MSR_IA32_MISC_ENABLE_EMON; data |= old_val & MSR_IA32_MISC_ENABLE_EMON; } if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT) && ((old_val ^ data) & MSR_IA32_MISC_ENABLE_MWAIT)) { if (!guest_cpuid_has(vcpu, X86_FEATURE_XMM3)) return 1; vcpu->arch.ia32_misc_enable_msr = data; kvm_update_cpuid_runtime(vcpu); } else { vcpu->arch.ia32_misc_enable_msr = data; } break; } case MSR_IA32_SMBASE: if (!IS_ENABLED(CONFIG_KVM_SMM) || !msr_info->host_initiated) return 1; vcpu->arch.smbase = data; break; case MSR_IA32_POWER_CTL: vcpu->arch.msr_ia32_power_ctl = data; break; case MSR_IA32_TSC: if (msr_info->host_initiated) { kvm_synchronize_tsc(vcpu, &data); } else { u64 adj = kvm_compute_l1_tsc_offset(vcpu, data) - vcpu->arch.l1_tsc_offset; adjust_tsc_offset_guest(vcpu, adj); vcpu->arch.ia32_tsc_adjust_msr += adj; } break; case MSR_IA32_XSS: if (!msr_info->host_initiated && !guest_cpuid_has(vcpu, X86_FEATURE_XSAVES)) return 1; /* * KVM supports exposing PT to the guest, but does not support * IA32_XSS[bit 8]. Guests have to use RDMSR/WRMSR rather than * XSAVES/XRSTORS to save/restore PT MSRs. */ if (data & ~kvm_caps.supported_xss) return 1; vcpu->arch.ia32_xss = data; kvm_update_cpuid_runtime(vcpu); break; case MSR_SMI_COUNT: if (!msr_info->host_initiated) return 1; vcpu->arch.smi_count = data; break; case MSR_KVM_WALL_CLOCK_NEW: if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2)) return 1; vcpu->kvm->arch.wall_clock = data; kvm_write_wall_clock(vcpu->kvm, data, 0); break; case MSR_KVM_WALL_CLOCK: if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE)) return 1; vcpu->kvm->arch.wall_clock = data; kvm_write_wall_clock(vcpu->kvm, data, 0); break; case MSR_KVM_SYSTEM_TIME_NEW: if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2)) return 1; kvm_write_system_time(vcpu, data, false, msr_info->host_initiated); break; case MSR_KVM_SYSTEM_TIME: if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE)) return 1; kvm_write_system_time(vcpu, data, true, msr_info->host_initiated); break; case MSR_KVM_ASYNC_PF_EN: if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF)) return 1; if (kvm_pv_enable_async_pf(vcpu, data)) return 1; break; case MSR_KVM_ASYNC_PF_INT: if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT)) return 1; if (kvm_pv_enable_async_pf_int(vcpu, data)) return 1; break; case MSR_KVM_ASYNC_PF_ACK: if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT)) return 1; if (data & 0x1) { vcpu->arch.apf.pageready_pending = false; kvm_check_async_pf_completion(vcpu); } break; case MSR_KVM_STEAL_TIME: if (!guest_pv_has(vcpu, KVM_FEATURE_STEAL_TIME)) return 1; if (unlikely(!sched_info_on())) return 1; if (data & KVM_STEAL_RESERVED_MASK) return 1; vcpu->arch.st.msr_val = data; if (!(data & KVM_MSR_ENABLED)) break; kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); break; case MSR_KVM_PV_EOI_EN: if (!guest_pv_has(vcpu, KVM_FEATURE_PV_EOI)) return 1; if (kvm_lapic_set_pv_eoi(vcpu, data, sizeof(u8))) return 1; break; case MSR_KVM_POLL_CONTROL: if (!guest_pv_has(vcpu, KVM_FEATURE_POLL_CONTROL)) return 1; /* only enable bit supported */ if (data & (-1ULL << 1)) return 1; vcpu->arch.msr_kvm_poll_control = data; break; case MSR_IA32_MCG_CTL: case MSR_IA32_MCG_STATUS: case MSR_IA32_MC0_CTL ... MSR_IA32_MCx_CTL(KVM_MAX_MCE_BANKS) - 1: case MSR_IA32_MC0_CTL2 ... MSR_IA32_MCx_CTL2(KVM_MAX_MCE_BANKS) - 1: return set_msr_mce(vcpu, msr_info); case MSR_K7_PERFCTR0 ... MSR_K7_PERFCTR3: case MSR_P6_PERFCTR0 ... MSR_P6_PERFCTR1: case MSR_K7_EVNTSEL0 ... MSR_K7_EVNTSEL3: case MSR_P6_EVNTSEL0 ... MSR_P6_EVNTSEL1: if (kvm_pmu_is_valid_msr(vcpu, msr)) return kvm_pmu_set_msr(vcpu, msr_info); if (data) kvm_pr_unimpl_wrmsr(vcpu, msr, data); break; case MSR_K7_CLK_CTL: /* * Ignore all writes to this no longer documented MSR. * Writes are only relevant for old K7 processors, * all pre-dating SVM, but a recommended workaround from * AMD for these chips. It is possible to specify the * affected processor models on the command line, hence * the need to ignore the workaround. */ break; #ifdef CONFIG_KVM_HYPERV case HV_X64_MSR_GUEST_OS_ID ... HV_X64_MSR_SINT15: case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER: case HV_X64_MSR_SYNDBG_OPTIONS: case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4: case HV_X64_MSR_CRASH_CTL: case HV_X64_MSR_STIMER0_CONFIG ... HV_X64_MSR_STIMER3_COUNT: case HV_X64_MSR_REENLIGHTENMENT_CONTROL: case HV_X64_MSR_TSC_EMULATION_CONTROL: case HV_X64_MSR_TSC_EMULATION_STATUS: case HV_X64_MSR_TSC_INVARIANT_CONTROL: return kvm_hv_set_msr_common(vcpu, msr, data, msr_info->host_initiated); #endif case MSR_IA32_BBL_CR_CTL3: /* Drop writes to this legacy MSR -- see rdmsr * counterpart for further detail. */ kvm_pr_unimpl_wrmsr(vcpu, msr, data); break; case MSR_AMD64_OSVW_ID_LENGTH: if (!guest_cpuid_has(vcpu, X86_FEATURE_OSVW)) return 1; vcpu->arch.osvw.length = data; break; case MSR_AMD64_OSVW_STATUS: if (!guest_cpuid_has(vcpu, X86_FEATURE_OSVW)) return 1; vcpu->arch.osvw.status = data; break; case MSR_PLATFORM_INFO: if (!msr_info->host_initiated || (!(data & MSR_PLATFORM_INFO_CPUID_FAULT) && cpuid_fault_enabled(vcpu))) return 1; vcpu->arch.msr_platform_info = data; break; case MSR_MISC_FEATURES_ENABLES: if (data & ~MSR_MISC_FEATURES_ENABLES_CPUID_FAULT || (data & MSR_MISC_FEATURES_ENABLES_CPUID_FAULT && !supports_cpuid_fault(vcpu))) return 1; vcpu->arch.msr_misc_features_enables = data; break; #ifdef CONFIG_X86_64 case MSR_IA32_XFD: if (!msr_info->host_initiated && !guest_cpuid_has(vcpu, X86_FEATURE_XFD)) return 1; if (data & ~kvm_guest_supported_xfd(vcpu)) return 1; fpu_update_guest_xfd(&vcpu->arch.guest_fpu, data); break; case MSR_IA32_XFD_ERR: if (!msr_info->host_initiated && !guest_cpuid_has(vcpu, X86_FEATURE_XFD)) return 1; if (data & ~kvm_guest_supported_xfd(vcpu)) return 1; vcpu->arch.guest_fpu.xfd_err = data; break; #endif default: if (kvm_pmu_is_valid_msr(vcpu, msr)) return kvm_pmu_set_msr(vcpu, msr_info); /* * Userspace is allowed to write '0' to MSRs that KVM reports * as to-be-saved, even if an MSRs isn't fully supported. */ if (msr_info->host_initiated && !data && kvm_is_msr_to_save(msr)) break; return KVM_MSR_RET_INVALID; } return 0; } EXPORT_SYMBOL_GPL(kvm_set_msr_common); static int get_msr_mce(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host) { u64 data; u64 mcg_cap = vcpu->arch.mcg_cap; unsigned bank_num = mcg_cap & 0xff; u32 offset, last_msr; switch (msr) { case MSR_IA32_P5_MC_ADDR: case MSR_IA32_P5_MC_TYPE: data = 0; break; case MSR_IA32_MCG_CAP: data = vcpu->arch.mcg_cap; break; case MSR_IA32_MCG_CTL: if (!(mcg_cap & MCG_CTL_P) && !host) return 1; data = vcpu->arch.mcg_ctl; break; case MSR_IA32_MCG_STATUS: data = vcpu->arch.mcg_status; break; case MSR_IA32_MC0_CTL2 ... MSR_IA32_MCx_CTL2(KVM_MAX_MCE_BANKS) - 1: last_msr = MSR_IA32_MCx_CTL2(bank_num) - 1; if (msr > last_msr) return 1; if (!(mcg_cap & MCG_CMCI_P) && !host) return 1; offset = array_index_nospec(msr - MSR_IA32_MC0_CTL2, last_msr + 1 - MSR_IA32_MC0_CTL2); data = vcpu->arch.mci_ctl2_banks[offset]; break; case MSR_IA32_MC0_CTL ... MSR_IA32_MCx_CTL(KVM_MAX_MCE_BANKS) - 1: last_msr = MSR_IA32_MCx_CTL(bank_num) - 1; if (msr > last_msr) return 1; offset = array_index_nospec(msr - MSR_IA32_MC0_CTL, last_msr + 1 - MSR_IA32_MC0_CTL); data = vcpu->arch.mce_banks[offset]; break; default: return 1; } *pdata = data; return 0; } int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) { switch (msr_info->index) { case MSR_IA32_PLATFORM_ID: case MSR_IA32_EBL_CR_POWERON: case MSR_IA32_LASTBRANCHFROMIP: case MSR_IA32_LASTBRANCHTOIP: case MSR_IA32_LASTINTFROMIP: case MSR_IA32_LASTINTTOIP: case MSR_AMD64_SYSCFG: case MSR_K8_TSEG_ADDR: case MSR_K8_TSEG_MASK: case MSR_VM_HSAVE_PA: case MSR_K8_INT_PENDING_MSG: case MSR_AMD64_NB_CFG: case MSR_FAM10H_MMIO_CONF_BASE: case MSR_AMD64_BU_CFG2: case MSR_IA32_PERF_CTL: case MSR_AMD64_DC_CFG: case MSR_AMD64_TW_CFG: case MSR_F15H_EX_CFG: /* * Intel Sandy Bridge CPUs must support the RAPL (running average power * limit) MSRs. Just return 0, as we do not want to expose the host * data here. Do not conditionalize this on CPUID, as KVM does not do * so for existing CPU-specific MSRs. */ case MSR_RAPL_POWER_UNIT: case MSR_PP0_ENERGY_STATUS: /* Power plane 0 (core) */ case MSR_PP1_ENERGY_STATUS: /* Power plane 1 (graphics uncore) */ case MSR_PKG_ENERGY_STATUS: /* Total package */ case MSR_DRAM_ENERGY_STATUS: /* DRAM controller */ msr_info->data = 0; break; case MSR_K7_EVNTSEL0 ... MSR_K7_EVNTSEL3: case MSR_K7_PERFCTR0 ... MSR_K7_PERFCTR3: case MSR_P6_PERFCTR0 ... MSR_P6_PERFCTR1: case MSR_P6_EVNTSEL0 ... MSR_P6_EVNTSEL1: if (kvm_pmu_is_valid_msr(vcpu, msr_info->index)) return kvm_pmu_get_msr(vcpu, msr_info); msr_info->data = 0; break; case MSR_IA32_UCODE_REV: msr_info->data = vcpu->arch.microcode_version; break; case MSR_IA32_ARCH_CAPABILITIES: if (!msr_info->host_initiated && !guest_cpuid_has(vcpu, X86_FEATURE_ARCH_CAPABILITIES)) return 1; msr_info->data = vcpu->arch.arch_capabilities; break; case MSR_IA32_PERF_CAPABILITIES: if (!msr_info->host_initiated && !guest_cpuid_has(vcpu, X86_FEATURE_PDCM)) return 1; msr_info->data = vcpu->arch.perf_capabilities; break; case MSR_IA32_POWER_CTL: msr_info->data = vcpu->arch.msr_ia32_power_ctl; break; case MSR_IA32_TSC: { /* * Intel SDM states that MSR_IA32_TSC read adds the TSC offset * even when not intercepted. AMD manual doesn't explicitly * state this but appears to behave the same. * * On userspace reads and writes, however, we unconditionally * return L1's TSC value to ensure backwards-compatible * behavior for migration. */ u64 offset, ratio; if (msr_info->host_initiated) { offset = vcpu->arch.l1_tsc_offset; ratio = vcpu->arch.l1_tsc_scaling_ratio; } else { offset = vcpu->arch.tsc_offset; ratio = vcpu->arch.tsc_scaling_ratio; } msr_info->data = kvm_scale_tsc(rdtsc(), ratio) + offset; break; } case MSR_IA32_CR_PAT: msr_info->data = vcpu->arch.pat; break; case MSR_MTRRcap: case MTRRphysBase_MSR(0) ... MSR_MTRRfix4K_F8000: case MSR_MTRRdefType: return kvm_mtrr_get_msr(vcpu, msr_info->index, &msr_info->data); case 0xcd: /* fsb frequency */ msr_info->data = 3; break; /* * MSR_EBC_FREQUENCY_ID * Conservative value valid for even the basic CPU models. * Models 0,1: 000 in bits 23:21 indicating a bus speed of * 100MHz, model 2 000 in bits 18:16 indicating 100MHz, * and 266MHz for model 3, or 4. Set Core Clock * Frequency to System Bus Frequency Ratio to 1 (bits * 31:24) even though these are only valid for CPU * models > 2, however guests may end up dividing or * multiplying by zero otherwise. */ case MSR_EBC_FREQUENCY_ID: msr_info->data = 1 << 24; break; case MSR_IA32_APICBASE: msr_info->data = kvm_get_apic_base(vcpu); break; case APIC_BASE_MSR ... APIC_BASE_MSR + 0xff: return kvm_x2apic_msr_read(vcpu, msr_info->index, &msr_info->data); case MSR_IA32_TSC_DEADLINE: msr_info->data = kvm_get_lapic_tscdeadline_msr(vcpu); break; case MSR_IA32_TSC_ADJUST: msr_info->data = (u64)vcpu->arch.ia32_tsc_adjust_msr; break; case MSR_IA32_MISC_ENABLE: msr_info->data = vcpu->arch.ia32_misc_enable_msr; break; case MSR_IA32_SMBASE: if (!IS_ENABLED(CONFIG_KVM_SMM) || !msr_info->host_initiated) return 1; msr_info->data = vcpu->arch.smbase; break; case MSR_SMI_COUNT: msr_info->data = vcpu->arch.smi_count; break; case MSR_IA32_PERF_STATUS: /* TSC increment by tick */ msr_info->data = 1000ULL; /* CPU multiplier */ msr_info->data |= (((uint64_t)4ULL) << 40); break; case MSR_EFER: msr_info->data = vcpu->arch.efer; break; case MSR_KVM_WALL_CLOCK: if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE)) return 1; msr_info->data = vcpu->kvm->arch.wall_clock; break; case MSR_KVM_WALL_CLOCK_NEW: if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2)) return 1; msr_info->data = vcpu->kvm->arch.wall_clock; break; case MSR_KVM_SYSTEM_TIME: if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE)) return 1; msr_info->data = vcpu->arch.time; break; case MSR_KVM_SYSTEM_TIME_NEW: if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2)) return 1; msr_info->data = vcpu->arch.time; break; case MSR_KVM_ASYNC_PF_EN: if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF)) return 1; msr_info->data = vcpu->arch.apf.msr_en_val; break; case MSR_KVM_ASYNC_PF_INT: if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT)) return 1; msr_info->data = vcpu->arch.apf.msr_int_val; break; case MSR_KVM_ASYNC_PF_ACK: if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT)) return 1; msr_info->data = 0; break; case MSR_KVM_STEAL_TIME: if (!guest_pv_has(vcpu, KVM_FEATURE_STEAL_TIME)) return 1; msr_info->data = vcpu->arch.st.msr_val; break; case MSR_KVM_PV_EOI_EN: if (!guest_pv_has(vcpu, KVM_FEATURE_PV_EOI)) return 1; msr_info->data = vcpu->arch.pv_eoi.msr_val; break; case MSR_KVM_POLL_CONTROL: if (!guest_pv_has(vcpu, KVM_FEATURE_POLL_CONTROL)) return 1; msr_info->data = vcpu->arch.msr_kvm_poll_control; break; case MSR_IA32_P5_MC_ADDR: case MSR_IA32_P5_MC_TYPE: case MSR_IA32_MCG_CAP: case MSR_IA32_MCG_CTL: case MSR_IA32_MCG_STATUS: case MSR_IA32_MC0_CTL ... MSR_IA32_MCx_CTL(KVM_MAX_MCE_BANKS) - 1: case MSR_IA32_MC0_CTL2 ... MSR_IA32_MCx_CTL2(KVM_MAX_MCE_BANKS) - 1: return get_msr_mce(vcpu, msr_info->index, &msr_info->data, msr_info->host_initiated); case MSR_IA32_XSS: if (!msr_info->host_initiated && !guest_cpuid_has(vcpu, X86_FEATURE_XSAVES)) return 1; msr_info->data = vcpu->arch.ia32_xss; break; case MSR_K7_CLK_CTL: /* * Provide expected ramp-up count for K7. All other * are set to zero, indicating minimum divisors for * every field. * * This prevents guest kernels on AMD host with CPU * type 6, model 8 and higher from exploding due to * the rdmsr failing. */ msr_info->data = 0x20000000; break; #ifdef CONFIG_KVM_HYPERV case HV_X64_MSR_GUEST_OS_ID ... HV_X64_MSR_SINT15: case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER: case HV_X64_MSR_SYNDBG_OPTIONS: case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4: case HV_X64_MSR_CRASH_CTL: case HV_X64_MSR_STIMER0_CONFIG ... HV_X64_MSR_STIMER3_COUNT: case HV_X64_MSR_REENLIGHTENMENT_CONTROL: case HV_X64_MSR_TSC_EMULATION_CONTROL: case HV_X64_MSR_TSC_EMULATION_STATUS: case HV_X64_MSR_TSC_INVARIANT_CONTROL: return kvm_hv_get_msr_common(vcpu, msr_info->index, &msr_info->data, msr_info->host_initiated); #endif case MSR_IA32_BBL_CR_CTL3: /* This legacy MSR exists but isn't fully documented in current * silicon. It is however accessed by winxp in very narrow * scenarios where it sets bit #19, itself documented as * a "reserved" bit. Best effort attempt to source coherent * read data here should the balance of the register be * interpreted by the guest: * * L2 cache control register 3: 64GB range, 256KB size, * enabled, latency 0x1, configured */ msr_info->data = 0xbe702111; break; case MSR_AMD64_OSVW_ID_LENGTH: if (!guest_cpuid_has(vcpu, X86_FEATURE_OSVW)) return 1; msr_info->data = vcpu->arch.osvw.length; break; case MSR_AMD64_OSVW_STATUS: if (!guest_cpuid_has(vcpu, X86_FEATURE_OSVW)) return 1; msr_info->data = vcpu->arch.osvw.status; break; case MSR_PLATFORM_INFO: if (!msr_info->host_initiated && !vcpu->kvm->arch.guest_can_read_msr_platform_info) return 1; msr_info->data = vcpu->arch.msr_platform_info; break; case MSR_MISC_FEATURES_ENABLES: msr_info->data = vcpu->arch.msr_misc_features_enables; break; case MSR_K7_HWCR: msr_info->data = vcpu->arch.msr_hwcr; break; #ifdef CONFIG_X86_64 case MSR_IA32_XFD: if (!msr_info->host_initiated && !guest_cpuid_has(vcpu, X86_FEATURE_XFD)) return 1; msr_info->data = vcpu->arch.guest_fpu.fpstate->xfd; break; case MSR_IA32_XFD_ERR: if (!msr_info->host_initiated && !guest_cpuid_has(vcpu, X86_FEATURE_XFD)) return 1; msr_info->data = vcpu->arch.guest_fpu.xfd_err; break; #endif default: if (kvm_pmu_is_valid_msr(vcpu, msr_info->index)) return kvm_pmu_get_msr(vcpu, msr_info); /* * Userspace is allowed to read MSRs that KVM reports as * to-be-saved, even if an MSR isn't fully supported. */ if (msr_info->host_initiated && kvm_is_msr_to_save(msr_info->index)) { msr_info->data = 0; break; } return KVM_MSR_RET_INVALID; } return 0; } EXPORT_SYMBOL_GPL(kvm_get_msr_common); /* * Read or write a bunch of msrs. All parameters are kernel addresses. * * @return number of msrs set successfully. */ static int __msr_io(struct kvm_vcpu *vcpu, struct kvm_msrs *msrs, struct kvm_msr_entry *entries, int (*do_msr)(struct kvm_vcpu *vcpu, unsigned index, u64 *data)) { int i; for (i = 0; i < msrs->nmsrs; ++i) if (do_msr(vcpu, entries[i].index, &entries[i].data)) break; return i; } /* * Read or write a bunch of msrs. Parameters are user addresses. * * @return number of msrs set successfully. */ static int msr_io(struct kvm_vcpu *vcpu, struct kvm_msrs __user *user_msrs, int (*do_msr)(struct kvm_vcpu *vcpu, unsigned index, u64 *data), int writeback) { struct kvm_msrs msrs; struct kvm_msr_entry *entries; unsigned size; int r; r = -EFAULT; if (copy_from_user(&msrs, user_msrs, sizeof(msrs))) goto out; r = -E2BIG; if (msrs.nmsrs >= MAX_IO_MSRS) goto out; size = sizeof(struct kvm_msr_entry) * msrs.nmsrs; entries = memdup_user(user_msrs->entries, size); if (IS_ERR(entries)) { r = PTR_ERR(entries); goto out; } r = __msr_io(vcpu, &msrs, entries, do_msr); if (writeback && copy_to_user(user_msrs->entries, entries, size)) r = -EFAULT; kfree(entries); out: return r; } static inline bool kvm_can_mwait_in_guest(void) { return boot_cpu_has(X86_FEATURE_MWAIT) && !boot_cpu_has_bug(X86_BUG_MONITOR) && boot_cpu_has(X86_FEATURE_ARAT); } #ifdef CONFIG_KVM_HYPERV static int kvm_ioctl_get_supported_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 __user *cpuid_arg) { struct kvm_cpuid2 cpuid; int r; r = -EFAULT; if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid))) return r; r = kvm_get_hv_cpuid(vcpu, &cpuid, cpuid_arg->entries); if (r) return r; r = -EFAULT; if (copy_to_user(cpuid_arg, &cpuid, sizeof(cpuid))) return r; return 0; } #endif static bool kvm_is_vm_type_supported(unsigned long type) { return type == KVM_X86_DEFAULT_VM || (type == KVM_X86_SW_PROTECTED_VM && IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_enabled); } int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) { int r = 0; switch (ext) { case KVM_CAP_IRQCHIP: case KVM_CAP_HLT: case KVM_CAP_MMU_SHADOW_CACHE_CONTROL: case KVM_CAP_SET_TSS_ADDR: case KVM_CAP_EXT_CPUID: case KVM_CAP_EXT_EMUL_CPUID: case KVM_CAP_CLOCKSOURCE: case KVM_CAP_PIT: case KVM_CAP_NOP_IO_DELAY: case KVM_CAP_MP_STATE: case KVM_CAP_SYNC_MMU: case KVM_CAP_USER_NMI: case KVM_CAP_REINJECT_CONTROL: case KVM_CAP_IRQ_INJECT_STATUS: case KVM_CAP_IOEVENTFD: case KVM_CAP_IOEVENTFD_NO_LENGTH: case KVM_CAP_PIT2: case KVM_CAP_PIT_STATE2: case KVM_CAP_SET_IDENTITY_MAP_ADDR: case KVM_CAP_VCPU_EVENTS: #ifdef CONFIG_KVM_HYPERV case KVM_CAP_HYPERV: case KVM_CAP_HYPERV_VAPIC: case KVM_CAP_HYPERV_SPIN: case KVM_CAP_HYPERV_TIME: case KVM_CAP_HYPERV_SYNIC: case KVM_CAP_HYPERV_SYNIC2: case KVM_CAP_HYPERV_VP_INDEX: case KVM_CAP_HYPERV_EVENTFD: case KVM_CAP_HYPERV_TLBFLUSH: case KVM_CAP_HYPERV_SEND_IPI: case KVM_CAP_HYPERV_CPUID: case KVM_CAP_HYPERV_ENFORCE_CPUID: case KVM_CAP_SYS_HYPERV_CPUID: #endif case KVM_CAP_PCI_SEGMENT: case KVM_CAP_DEBUGREGS: case KVM_CAP_X86_ROBUST_SINGLESTEP: case KVM_CAP_XSAVE: case KVM_CAP_ASYNC_PF: case KVM_CAP_ASYNC_PF_INT: case KVM_CAP_GET_TSC_KHZ: case KVM_CAP_KVMCLOCK_CTRL: case KVM_CAP_READONLY_MEM: case KVM_CAP_IOAPIC_POLARITY_IGNORED: case KVM_CAP_TSC_DEADLINE_TIMER: case KVM_CAP_DISABLE_QUIRKS: case KVM_CAP_SET_BOOT_CPU_ID: case KVM_CAP_SPLIT_IRQCHIP: case KVM_CAP_IMMEDIATE_EXIT: case KVM_CAP_PMU_EVENT_FILTER: case KVM_CAP_PMU_EVENT_MASKED_EVENTS: case KVM_CAP_GET_MSR_FEATURES: case KVM_CAP_MSR_PLATFORM_INFO: case KVM_CAP_EXCEPTION_PAYLOAD: case KVM_CAP_X86_TRIPLE_FAULT_EVENT: case KVM_CAP_SET_GUEST_DEBUG: case KVM_CAP_LAST_CPU: case KVM_CAP_X86_USER_SPACE_MSR: case KVM_CAP_X86_MSR_FILTER: case KVM_CAP_ENFORCE_PV_FEATURE_CPUID: #ifdef CONFIG_X86_SGX_KVM case KVM_CAP_SGX_ATTRIBUTE: #endif case KVM_CAP_VM_COPY_ENC_CONTEXT_FROM: case KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM: case KVM_CAP_SREGS2: case KVM_CAP_EXIT_ON_EMULATION_FAILURE: case KVM_CAP_VCPU_ATTRIBUTES: case KVM_CAP_SYS_ATTRIBUTES: case KVM_CAP_VAPIC: case KVM_CAP_ENABLE_CAP: case KVM_CAP_VM_DISABLE_NX_HUGE_PAGES: case KVM_CAP_IRQFD_RESAMPLE: case KVM_CAP_MEMORY_FAULT_INFO: r = 1; break; case KVM_CAP_EXIT_HYPERCALL: r = KVM_EXIT_HYPERCALL_VALID_MASK; break; case KVM_CAP_SET_GUEST_DEBUG2: return KVM_GUESTDBG_VALID_MASK; #ifdef CONFIG_KVM_XEN case KVM_CAP_XEN_HVM: r = KVM_XEN_HVM_CONFIG_HYPERCALL_MSR | KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL | KVM_XEN_HVM_CONFIG_SHARED_INFO | KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL | KVM_XEN_HVM_CONFIG_EVTCHN_SEND | KVM_XEN_HVM_CONFIG_PVCLOCK_TSC_UNSTABLE; if (sched_info_on()) r |= KVM_XEN_HVM_CONFIG_RUNSTATE | KVM_XEN_HVM_CONFIG_RUNSTATE_UPDATE_FLAG; break; #endif case KVM_CAP_SYNC_REGS: r = KVM_SYNC_X86_VALID_FIELDS; break; case KVM_CAP_ADJUST_CLOCK: r = KVM_CLOCK_VALID_FLAGS; break; case KVM_CAP_X86_DISABLE_EXITS: r = KVM_X86_DISABLE_EXITS_PAUSE; if (!mitigate_smt_rsb) { r |= KVM_X86_DISABLE_EXITS_HLT | KVM_X86_DISABLE_EXITS_CSTATE; if (kvm_can_mwait_in_guest()) r |= KVM_X86_DISABLE_EXITS_MWAIT; } break; case KVM_CAP_X86_SMM: if (!IS_ENABLED(CONFIG_KVM_SMM)) break; /* SMBASE is usually relocated above 1M on modern chipsets, * and SMM handlers might indeed rely on 4G segment limits, * so do not report SMM to be available if real mode is * emulated via vm86 mode. Still, do not go to great lengths * to avoid userspace's usage of the feature, because it is a * fringe case that is not enabled except via specific settings * of the module parameters. */ r = static_call(kvm_x86_has_emulated_msr)(kvm, MSR_IA32_SMBASE); break; case KVM_CAP_NR_VCPUS: r = min_t(unsigned int, num_online_cpus(), KVM_MAX_VCPUS); break; case KVM_CAP_MAX_VCPUS: r = KVM_MAX_VCPUS; break; case KVM_CAP_MAX_VCPU_ID: r = KVM_MAX_VCPU_IDS; break; case KVM_CAP_PV_MMU: /* obsolete */ r = 0; break; case KVM_CAP_MCE: r = KVM_MAX_MCE_BANKS; break; case KVM_CAP_XCRS: r = boot_cpu_has(X86_FEATURE_XSAVE); break; case KVM_CAP_TSC_CONTROL: case KVM_CAP_VM_TSC_CONTROL: r = kvm_caps.has_tsc_control; break; case KVM_CAP_X2APIC_API: r = KVM_X2APIC_API_VALID_FLAGS; break; case KVM_CAP_NESTED_STATE: r = kvm_x86_ops.nested_ops->get_state ? kvm_x86_ops.nested_ops->get_state(NULL, NULL, 0) : 0; break; #ifdef CONFIG_KVM_HYPERV case KVM_CAP_HYPERV_DIRECT_TLBFLUSH: r = kvm_x86_ops.enable_l2_tlb_flush != NULL; break; case KVM_CAP_HYPERV_ENLIGHTENED_VMCS: r = kvm_x86_ops.nested_ops->enable_evmcs != NULL; break; #endif case KVM_CAP_SMALLER_MAXPHYADDR: r = (int) allow_smaller_maxphyaddr; break; case KVM_CAP_STEAL_TIME: r = sched_info_on(); break; case KVM_CAP_X86_BUS_LOCK_EXIT: if (kvm_caps.has_bus_lock_exit) r = KVM_BUS_LOCK_DETECTION_OFF | KVM_BUS_LOCK_DETECTION_EXIT; else r = 0; break; case KVM_CAP_XSAVE2: { r = xstate_required_size(kvm_get_filtered_xcr0(), false); if (r < sizeof(struct kvm_xsave)) r = sizeof(struct kvm_xsave); break; } case KVM_CAP_PMU_CAPABILITY: r = enable_pmu ? KVM_CAP_PMU_VALID_MASK : 0; break; case KVM_CAP_DISABLE_QUIRKS2: r = KVM_X86_VALID_QUIRKS; break; case KVM_CAP_X86_NOTIFY_VMEXIT: r = kvm_caps.has_notify_vmexit; break; case KVM_CAP_VM_TYPES: r = BIT(KVM_X86_DEFAULT_VM); if (kvm_is_vm_type_supported(KVM_X86_SW_PROTECTED_VM)) r |= BIT(KVM_X86_SW_PROTECTED_VM); break; default: break; } return r; } static inline void __user *kvm_get_attr_addr(struct kvm_device_attr *attr) { void __user *uaddr = (void __user*)(unsigned long)attr->addr; if ((u64)(unsigned long)uaddr != attr->addr) return ERR_PTR_USR(-EFAULT); return uaddr; } static int kvm_x86_dev_get_attr(struct kvm_device_attr *attr) { u64 __user *uaddr = kvm_get_attr_addr(attr); if (attr->group) return -ENXIO; if (IS_ERR(uaddr)) return PTR_ERR(uaddr); switch (attr->attr) { case KVM_X86_XCOMP_GUEST_SUPP: if (put_user(kvm_caps.supported_xcr0, uaddr)) return -EFAULT; return 0; default: return -ENXIO; } } static int kvm_x86_dev_has_attr(struct kvm_device_attr *attr) { if (attr->group) return -ENXIO; switch (attr->attr) { case KVM_X86_XCOMP_GUEST_SUPP: return 0; default: return -ENXIO; } } long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { void __user *argp = (void __user *)arg; long r; switch (ioctl) { case KVM_GET_MSR_INDEX_LIST: { struct kvm_msr_list __user *user_msr_list = argp; struct kvm_msr_list msr_list; unsigned n; r = -EFAULT; if (copy_from_user(&msr_list, user_msr_list, sizeof(msr_list))) goto out; n = msr_list.nmsrs; msr_list.nmsrs = num_msrs_to_save + num_emulated_msrs; if (copy_to_user(user_msr_list, &msr_list, sizeof(msr_list))) goto out; r = -E2BIG; if (n < msr_list.nmsrs) goto out; r = -EFAULT; if (copy_to_user(user_msr_list->indices, &msrs_to_save, num_msrs_to_save * sizeof(u32))) goto out; if (copy_to_user(user_msr_list->indices + num_msrs_to_save, &emulated_msrs, num_emulated_msrs * sizeof(u32))) goto out; r = 0; break; } case KVM_GET_SUPPORTED_CPUID: case KVM_GET_EMULATED_CPUID: { struct kvm_cpuid2 __user *cpuid_arg = argp; struct kvm_cpuid2 cpuid; r = -EFAULT; if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid))) goto out; r = kvm_dev_ioctl_get_cpuid(&cpuid, cpuid_arg->entries, ioctl); if (r) goto out; r = -EFAULT; if (copy_to_user(cpuid_arg, &cpuid, sizeof(cpuid))) goto out; r = 0; break; } case KVM_X86_GET_MCE_CAP_SUPPORTED: r = -EFAULT; if (copy_to_user(argp, &kvm_caps.supported_mce_cap, sizeof(kvm_caps.supported_mce_cap))) goto out; r = 0; break; case KVM_GET_MSR_FEATURE_INDEX_LIST: { struct kvm_msr_list __user *user_msr_list = argp; struct kvm_msr_list msr_list; unsigned int n; r = -EFAULT; if (copy_from_user(&msr_list, user_msr_list, sizeof(msr_list))) goto out; n = msr_list.nmsrs; msr_list.nmsrs = num_msr_based_features; if (copy_to_user(user_msr_list, &msr_list, sizeof(msr_list))) goto out; r = -E2BIG; if (n < msr_list.nmsrs) goto out; r = -EFAULT; if (copy_to_user(user_msr_list->indices, &msr_based_features, num_msr_based_features * sizeof(u32))) goto out; r = 0; break; } case KVM_GET_MSRS: r = msr_io(NULL, argp, do_get_msr_feature, 1); break; #ifdef CONFIG_KVM_HYPERV case KVM_GET_SUPPORTED_HV_CPUID: r = kvm_ioctl_get_supported_hv_cpuid(NULL, argp); break; #endif case KVM_GET_DEVICE_ATTR: { struct kvm_device_attr attr; r = -EFAULT; if (copy_from_user(&attr, (void __user *)arg, sizeof(attr))) break; r = kvm_x86_dev_get_attr(&attr); break; } case KVM_HAS_DEVICE_ATTR: { struct kvm_device_attr attr; r = -EFAULT; if (copy_from_user(&attr, (void __user *)arg, sizeof(attr))) break; r = kvm_x86_dev_has_attr(&attr); break; } default: r = -EINVAL; break; } out: return r; } static void wbinvd_ipi(void *garbage) { wbinvd(); } static bool need_emulate_wbinvd(struct kvm_vcpu *vcpu) { return kvm_arch_has_noncoherent_dma(vcpu->kvm); } void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) { /* Address WBINVD may be executed by guest */ if (need_emulate_wbinvd(vcpu)) { if (static_call(kvm_x86_has_wbinvd_exit)()) cpumask_set_cpu(cpu, vcpu->arch.wbinvd_dirty_mask); else if (vcpu->cpu != -1 && vcpu->cpu != cpu) smp_call_function_single(vcpu->cpu, wbinvd_ipi, NULL, 1); } static_call(kvm_x86_vcpu_load)(vcpu, cpu); /* Save host pkru register if supported */ vcpu->arch.host_pkru = read_pkru(); /* Apply any externally detected TSC adjustments (due to suspend) */ if (unlikely(vcpu->arch.tsc_offset_adjustment)) { adjust_tsc_offset_host(vcpu, vcpu->arch.tsc_offset_adjustment); vcpu->arch.tsc_offset_adjustment = 0; kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu); } if (unlikely(vcpu->cpu != cpu) || kvm_check_tsc_unstable()) { s64 tsc_delta = !vcpu->arch.last_host_tsc ? 0 : rdtsc() - vcpu->arch.last_host_tsc; if (tsc_delta < 0) mark_tsc_unstable("KVM discovered backwards TSC"); if (kvm_check_tsc_unstable()) { u64 offset = kvm_compute_l1_tsc_offset(vcpu, vcpu->arch.last_guest_tsc); kvm_vcpu_write_tsc_offset(vcpu, offset); vcpu->arch.tsc_catchup = 1; } if (kvm_lapic_hv_timer_in_use(vcpu)) kvm_lapic_restart_hv_timer(vcpu); /* * On a host with synchronized TSC, there is no need to update * kvmclock on vcpu->cpu migration */ if (!vcpu->kvm->arch.use_master_clock || vcpu->cpu == -1) kvm_make_request(KVM_REQ_GLOBAL_CLOCK_UPDATE, vcpu); if (vcpu->cpu != cpu) kvm_make_request(KVM_REQ_MIGRATE_TIMER, vcpu); vcpu->cpu = cpu; } kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); } static void kvm_steal_time_set_preempted(struct kvm_vcpu *vcpu) { struct gfn_to_hva_cache *ghc = &vcpu->arch.st.cache; struct kvm_steal_time __user *st; struct kvm_memslots *slots; static const u8 preempted = KVM_VCPU_PREEMPTED; gpa_t gpa = vcpu->arch.st.msr_val & KVM_STEAL_VALID_BITS; /* * The vCPU can be marked preempted if and only if the VM-Exit was on * an instruction boundary and will not trigger guest emulation of any * kind (see vcpu_run). Vendor specific code controls (conservatively) * when this is true, for example allowing the vCPU to be marked * preempted if and only if the VM-Exit was due to a host interrupt. */ if (!vcpu->arch.at_instruction_boundary) { vcpu->stat.preemption_other++; return; } vcpu->stat.preemption_reported++; if (!(vcpu->arch.st.msr_val & KVM_MSR_ENABLED)) return; if (vcpu->arch.st.preempted) return; /* This happens on process exit */ if (unlikely(current->mm != vcpu->kvm->mm)) return; slots = kvm_memslots(vcpu->kvm); if (unlikely(slots->generation != ghc->generation || gpa != ghc->gpa || kvm_is_error_hva(ghc->hva) || !ghc->memslot)) return; st = (struct kvm_steal_time __user *)ghc->hva; BUILD_BUG_ON(sizeof(st->preempted) != sizeof(preempted)); if (!copy_to_user_nofault(&st->preempted, &preempted, sizeof(preempted))) vcpu->arch.st.preempted = KVM_VCPU_PREEMPTED; mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa)); } void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) { int idx; if (vcpu->preempted) { vcpu->arch.preempted_in_kernel = kvm_arch_vcpu_in_kernel(vcpu); /* * Take the srcu lock as memslots will be accessed to check the gfn * cache generation against the memslots generation. */ idx = srcu_read_lock(&vcpu->kvm->srcu); if (kvm_xen_msr_enabled(vcpu->kvm)) kvm_xen_runstate_set_preempted(vcpu); else kvm_steal_time_set_preempted(vcpu); srcu_read_unlock(&vcpu->kvm->srcu, idx); } static_call(kvm_x86_vcpu_put)(vcpu); vcpu->arch.last_host_tsc = rdtsc(); } static int kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s) { static_call_cond(kvm_x86_sync_pir_to_irr)(vcpu); return kvm_apic_get_state(vcpu, s); } static int kvm_vcpu_ioctl_set_lapic(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s) { int r; r = kvm_apic_set_state(vcpu, s); if (r) return r; update_cr8_intercept(vcpu); return 0; } static int kvm_cpu_accept_dm_intr(struct kvm_vcpu *vcpu) { /* * We can accept userspace's request for interrupt injection * as long as we have a place to store the interrupt number. * The actual injection will happen when the CPU is able to * deliver the interrupt. */ if (kvm_cpu_has_extint(vcpu)) return false; /* Acknowledging ExtINT does not happen if LINT0 is masked. */ return (!lapic_in_kernel(vcpu) || kvm_apic_accept_pic_intr(vcpu)); } static int kvm_vcpu_ready_for_interrupt_injection(struct kvm_vcpu *vcpu) { /* * Do not cause an interrupt window exit if an exception * is pending or an event needs reinjection; userspace * might want to inject the interrupt manually using KVM_SET_REGS * or KVM_SET_SREGS. For that to work, we must be at an * instruction boundary and with no events half-injected. */ return (kvm_arch_interrupt_allowed(vcpu) && kvm_cpu_accept_dm_intr(vcpu) && !kvm_event_needs_reinjection(vcpu) && !kvm_is_exception_pending(vcpu)); } static int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, struct kvm_interrupt *irq) { if (irq->irq >= KVM_NR_INTERRUPTS) return -EINVAL; if (!irqchip_in_kernel(vcpu->kvm)) { kvm_queue_interrupt(vcpu, irq->irq, false); kvm_make_request(KVM_REQ_EVENT, vcpu); return 0; } /* * With in-kernel LAPIC, we only use this to inject EXTINT, so * fail for in-kernel 8259. */ if (pic_in_kernel(vcpu->kvm)) return -ENXIO; if (vcpu->arch.pending_external_vector != -1) return -EEXIST; vcpu->arch.pending_external_vector = irq->irq; kvm_make_request(KVM_REQ_EVENT, vcpu); return 0; } static int kvm_vcpu_ioctl_nmi(struct kvm_vcpu *vcpu) { kvm_inject_nmi(vcpu); return 0; } static int vcpu_ioctl_tpr_access_reporting(struct kvm_vcpu *vcpu, struct kvm_tpr_access_ctl *tac) { if (tac->flags) return -EINVAL; vcpu->arch.tpr_access_reporting = !!tac->enabled; return 0; } static int kvm_vcpu_ioctl_x86_setup_mce(struct kvm_vcpu *vcpu, u64 mcg_cap) { int r; unsigned bank_num = mcg_cap & 0xff, bank; r = -EINVAL; if (!bank_num || bank_num > KVM_MAX_MCE_BANKS) goto out; if (mcg_cap & ~(kvm_caps.supported_mce_cap | 0xff | 0xff0000)) goto out; r = 0; vcpu->arch.mcg_cap = mcg_cap; /* Init IA32_MCG_CTL to all 1s */ if (mcg_cap & MCG_CTL_P) vcpu->arch.mcg_ctl = ~(u64)0; /* Init IA32_MCi_CTL to all 1s, IA32_MCi_CTL2 to all 0s */ for (bank = 0; bank < bank_num; bank++) { vcpu->arch.mce_banks[bank*4] = ~(u64)0; if (mcg_cap & MCG_CMCI_P) vcpu->arch.mci_ctl2_banks[bank] = 0; } kvm_apic_after_set_mcg_cap(vcpu); static_call(kvm_x86_setup_mce)(vcpu); out: return r; } /* * Validate this is an UCNA (uncorrectable no action) error by checking the * MCG_STATUS and MCi_STATUS registers: * - none of the bits for Machine Check Exceptions are set * - both the VAL (valid) and UC (uncorrectable) bits are set * MCI_STATUS_PCC - Processor Context Corrupted * MCI_STATUS_S - Signaled as a Machine Check Exception * MCI_STATUS_AR - Software recoverable Action Required */ static bool is_ucna(struct kvm_x86_mce *mce) { return !mce->mcg_status && !(mce->status & (MCI_STATUS_PCC | MCI_STATUS_S | MCI_STATUS_AR)) && (mce->status & MCI_STATUS_VAL) && (mce->status & MCI_STATUS_UC); } static int kvm_vcpu_x86_set_ucna(struct kvm_vcpu *vcpu, struct kvm_x86_mce *mce, u64* banks) { u64 mcg_cap = vcpu->arch.mcg_cap; banks[1] = mce->status; banks[2] = mce->addr; banks[3] = mce->misc; vcpu->arch.mcg_status = mce->mcg_status; if (!(mcg_cap & MCG_CMCI_P) || !(vcpu->arch.mci_ctl2_banks[mce->bank] & MCI_CTL2_CMCI_EN)) return 0; if (lapic_in_kernel(vcpu)) kvm_apic_local_deliver(vcpu->arch.apic, APIC_LVTCMCI); return 0; } static int kvm_vcpu_ioctl_x86_set_mce(struct kvm_vcpu *vcpu, struct kvm_x86_mce *mce) { u64 mcg_cap = vcpu->arch.mcg_cap; unsigned bank_num = mcg_cap & 0xff; u64 *banks = vcpu->arch.mce_banks; if (mce->bank >= bank_num || !(mce->status & MCI_STATUS_VAL)) return -EINVAL; banks += array_index_nospec(4 * mce->bank, 4 * bank_num); if (is_ucna(mce)) return kvm_vcpu_x86_set_ucna(vcpu, mce, banks); /* * if IA32_MCG_CTL is not all 1s, the uncorrected error * reporting is disabled */ if ((mce->status & MCI_STATUS_UC) && (mcg_cap & MCG_CTL_P) && vcpu->arch.mcg_ctl != ~(u64)0) return 0; /* * if IA32_MCi_CTL is not all 1s, the uncorrected error * reporting is disabled for the bank */ if ((mce->status & MCI_STATUS_UC) && banks[0] != ~(u64)0) return 0; if (mce->status & MCI_STATUS_UC) { if ((vcpu->arch.mcg_status & MCG_STATUS_MCIP) || !kvm_is_cr4_bit_set(vcpu, X86_CR4_MCE)) { kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu); return 0; } if (banks[1] & MCI_STATUS_VAL) mce->status |= MCI_STATUS_OVER; banks[2] = mce->addr; banks[3] = mce->misc; vcpu->arch.mcg_status = mce->mcg_status; banks[1] = mce->status; kvm_queue_exception(vcpu, MC_VECTOR); } else if (!(banks[1] & MCI_STATUS_VAL) || !(banks[1] & MCI_STATUS_UC)) { if (banks[1] & MCI_STATUS_VAL) mce->status |= MCI_STATUS_OVER; banks[2] = mce->addr; banks[3] = mce->misc; banks[1] = mce->status; } else banks[1] |= MCI_STATUS_OVER; return 0; } static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu, struct kvm_vcpu_events *events) { struct kvm_queued_exception *ex; process_nmi(vcpu); #ifdef CONFIG_KVM_SMM if (kvm_check_request(KVM_REQ_SMI, vcpu)) process_smi(vcpu); #endif /* * KVM's ABI only allows for one exception to be migrated. Luckily, * the only time there can be two queued exceptions is if there's a * non-exiting _injected_ exception, and a pending exiting exception. * In that case, ignore the VM-Exiting exception as it's an extension * of the injected exception. */ if (vcpu->arch.exception_vmexit.pending && !vcpu->arch.exception.pending && !vcpu->arch.exception.injected) ex = &vcpu->arch.exception_vmexit; else ex = &vcpu->arch.exception; /* * In guest mode, payload delivery should be deferred if the exception * will be intercepted by L1, e.g. KVM should not modifying CR2 if L1 * intercepts #PF, ditto for DR6 and #DBs. If the per-VM capability, * KVM_CAP_EXCEPTION_PAYLOAD, is not set, userspace may or may not * propagate the payload and so it cannot be safely deferred. Deliver * the payload if the capability hasn't been requested. */ if (!vcpu->kvm->arch.exception_payload_enabled && ex->pending && ex->has_payload) kvm_deliver_exception_payload(vcpu, ex); memset(events, 0, sizeof(*events)); /* * The API doesn't provide the instruction length for software * exceptions, so don't report them. As long as the guest RIP * isn't advanced, we should expect to encounter the exception * again. */ if (!kvm_exception_is_soft(ex->vector)) { events->exception.injected = ex->injected; events->exception.pending = ex->pending; /* * For ABI compatibility, deliberately conflate * pending and injected exceptions when * KVM_CAP_EXCEPTION_PAYLOAD isn't enabled. */ if (!vcpu->kvm->arch.exception_payload_enabled) events->exception.injected |= ex->pending; } events->exception.nr = ex->vector; events->exception.has_error_code = ex->has_error_code; events->exception.error_code = ex->error_code; events->exception_has_payload = ex->has_payload; events->exception_payload = ex->payload; events->interrupt.injected = vcpu->arch.interrupt.injected && !vcpu->arch.interrupt.soft; events->interrupt.nr = vcpu->arch.interrupt.nr; events->interrupt.shadow = static_call(kvm_x86_get_interrupt_shadow)(vcpu); events->nmi.injected = vcpu->arch.nmi_injected; events->nmi.pending = kvm_get_nr_pending_nmis(vcpu); events->nmi.masked = static_call(kvm_x86_get_nmi_mask)(vcpu); /* events->sipi_vector is never valid when reporting to user space */ #ifdef CONFIG_KVM_SMM events->smi.smm = is_smm(vcpu); events->smi.pending = vcpu->arch.smi_pending; events->smi.smm_inside_nmi = !!(vcpu->arch.hflags & HF_SMM_INSIDE_NMI_MASK); #endif events->smi.latched_init = kvm_lapic_latched_init(vcpu); events->flags = (KVM_VCPUEVENT_VALID_NMI_PENDING | KVM_VCPUEVENT_VALID_SHADOW | KVM_VCPUEVENT_VALID_SMM); if (vcpu->kvm->arch.exception_payload_enabled) events->flags |= KVM_VCPUEVENT_VALID_PAYLOAD; if (vcpu->kvm->arch.triple_fault_event) { events->triple_fault.pending = kvm_test_request(KVM_REQ_TRIPLE_FAULT, vcpu); events->flags |= KVM_VCPUEVENT_VALID_TRIPLE_FAULT; } } static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu, struct kvm_vcpu_events *events) { if (events->flags & ~(KVM_VCPUEVENT_VALID_NMI_PENDING | KVM_VCPUEVENT_VALID_SIPI_VECTOR | KVM_VCPUEVENT_VALID_SHADOW | KVM_VCPUEVENT_VALID_SMM | KVM_VCPUEVENT_VALID_PAYLOAD | KVM_VCPUEVENT_VALID_TRIPLE_FAULT)) return -EINVAL; if (events->flags & KVM_VCPUEVENT_VALID_PAYLOAD) { if (!vcpu->kvm->arch.exception_payload_enabled) return -EINVAL; if (events->exception.pending) events->exception.injected = 0; else events->exception_has_payload = 0; } else { events->exception.pending = 0; events->exception_has_payload = 0; } if ((events->exception.injected || events->exception.pending) && (events->exception.nr > 31 || events->exception.nr == NMI_VECTOR)) return -EINVAL; /* INITs are latched while in SMM */ if (events->flags & KVM_VCPUEVENT_VALID_SMM && (events->smi.smm || events->smi.pending) && vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED) return -EINVAL; process_nmi(vcpu); /* * Flag that userspace is stuffing an exception, the next KVM_RUN will * morph the exception to a VM-Exit if appropriate. Do this only for * pending exceptions, already-injected exceptions are not subject to * intercpetion. Note, userspace that conflates pending and injected * is hosed, and will incorrectly convert an injected exception into a * pending exception, which in turn may cause a spurious VM-Exit. */ vcpu->arch.exception_from_userspace = events->exception.pending; vcpu->arch.exception_vmexit.pending = false; vcpu->arch.exception.injected = events->exception.injected; vcpu->arch.exception.pending = events->exception.pending; vcpu->arch.exception.vector = events->exception.nr; vcpu->arch.exception.has_error_code = events->exception.has_error_code; vcpu->arch.exception.error_code = events->exception.error_code; vcpu->arch.exception.has_payload = events->exception_has_payload; vcpu->arch.exception.payload = events->exception_payload; vcpu->arch.interrupt.injected = events->interrupt.injected; vcpu->arch.interrupt.nr = events->interrupt.nr; vcpu->arch.interrupt.soft = events->interrupt.soft; if (events->flags & KVM_VCPUEVENT_VALID_SHADOW) static_call(kvm_x86_set_interrupt_shadow)(vcpu, events->interrupt.shadow); vcpu->arch.nmi_injected = events->nmi.injected; if (events->flags & KVM_VCPUEVENT_VALID_NMI_PENDING) { vcpu->arch.nmi_pending = 0; atomic_set(&vcpu->arch.nmi_queued, events->nmi.pending); kvm_make_request(KVM_REQ_NMI, vcpu); } static_call(kvm_x86_set_nmi_mask)(vcpu, events->nmi.masked); if (events->flags & KVM_VCPUEVENT_VALID_SIPI_VECTOR && lapic_in_kernel(vcpu)) vcpu->arch.apic->sipi_vector = events->sipi_vector; if (events->flags & KVM_VCPUEVENT_VALID_SMM) { #ifdef CONFIG_KVM_SMM if (!!(vcpu->arch.hflags & HF_SMM_MASK) != events->smi.smm) { kvm_leave_nested(vcpu); kvm_smm_changed(vcpu, events->smi.smm); } vcpu->arch.smi_pending = events->smi.pending; if (events->smi.smm) { if (events->smi.smm_inside_nmi) vcpu->arch.hflags |= HF_SMM_INSIDE_NMI_MASK; else vcpu->arch.hflags &= ~HF_SMM_INSIDE_NMI_MASK; } #else if (events->smi.smm || events->smi.pending || events->smi.smm_inside_nmi) return -EINVAL; #endif if (lapic_in_kernel(vcpu)) { if (events->smi.latched_init) set_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events); else clear_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events); } } if (events->flags & KVM_VCPUEVENT_VALID_TRIPLE_FAULT) { if (!vcpu->kvm->arch.triple_fault_event) return -EINVAL; if (events->triple_fault.pending) kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu); else kvm_clear_request(KVM_REQ_TRIPLE_FAULT, vcpu); } kvm_make_request(KVM_REQ_EVENT, vcpu); return 0; } static void kvm_vcpu_ioctl_x86_get_debugregs(struct kvm_vcpu *vcpu, struct kvm_debugregs *dbgregs) { unsigned int i; memset(dbgregs, 0, sizeof(*dbgregs)); BUILD_BUG_ON(ARRAY_SIZE(vcpu->arch.db) != ARRAY_SIZE(dbgregs->db)); for (i = 0; i < ARRAY_SIZE(vcpu->arch.db); i++) dbgregs->db[i] = vcpu->arch.db[i]; dbgregs->dr6 = vcpu->arch.dr6; dbgregs->dr7 = vcpu->arch.dr7; } static int kvm_vcpu_ioctl_x86_set_debugregs(struct kvm_vcpu *vcpu, struct kvm_debugregs *dbgregs) { unsigned int i; if (dbgregs->flags) return -EINVAL; if (!kvm_dr6_valid(dbgregs->dr6)) return -EINVAL; if (!kvm_dr7_valid(dbgregs->dr7)) return -EINVAL; for (i = 0; i < ARRAY_SIZE(vcpu->arch.db); i++) vcpu->arch.db[i] = dbgregs->db[i]; kvm_update_dr0123(vcpu); vcpu->arch.dr6 = dbgregs->dr6; vcpu->arch.dr7 = dbgregs->dr7; kvm_update_dr7(vcpu); return 0; } static void kvm_vcpu_ioctl_x86_get_xsave2(struct kvm_vcpu *vcpu, u8 *state, unsigned int size) { /* * Only copy state for features that are enabled for the guest. The * state itself isn't problematic, but setting bits in the header for * features that are supported in *this* host but not exposed to the * guest can result in KVM_SET_XSAVE failing when live migrating to a * compatible host without the features that are NOT exposed to the * guest. * * FP+SSE can always be saved/restored via KVM_{G,S}ET_XSAVE, even if * XSAVE/XCRO are not exposed to the guest, and even if XSAVE isn't * supported by the host. */ u64 supported_xcr0 = vcpu->arch.guest_supported_xcr0 | XFEATURE_MASK_FPSSE; if (fpstate_is_confidential(&vcpu->arch.guest_fpu)) return; fpu_copy_guest_fpstate_to_uabi(&vcpu->arch.guest_fpu, state, size, supported_xcr0, vcpu->arch.pkru); } static void kvm_vcpu_ioctl_x86_get_xsave(struct kvm_vcpu *vcpu, struct kvm_xsave *guest_xsave) { kvm_vcpu_ioctl_x86_get_xsave2(vcpu, (void *)guest_xsave->region, sizeof(guest_xsave->region)); } static int kvm_vcpu_ioctl_x86_set_xsave(struct kvm_vcpu *vcpu, struct kvm_xsave *guest_xsave) { if (fpstate_is_confidential(&vcpu->arch.guest_fpu)) return 0; return fpu_copy_uabi_to_guest_fpstate(&vcpu->arch.guest_fpu, guest_xsave->region, kvm_caps.supported_xcr0, &vcpu->arch.pkru); } static void kvm_vcpu_ioctl_x86_get_xcrs(struct kvm_vcpu *vcpu, struct kvm_xcrs *guest_xcrs) { if (!boot_cpu_has(X86_FEATURE_XSAVE)) { guest_xcrs->nr_xcrs = 0; return; } guest_xcrs->nr_xcrs = 1; guest_xcrs->flags = 0; guest_xcrs->xcrs[0].xcr = XCR_XFEATURE_ENABLED_MASK; guest_xcrs->xcrs[0].value = vcpu->arch.xcr0; } static int kvm_vcpu_ioctl_x86_set_xcrs(struct kvm_vcpu *vcpu, struct kvm_xcrs *guest_xcrs) { int i, r = 0; if (!boot_cpu_has(X86_FEATURE_XSAVE)) return -EINVAL; if (guest_xcrs->nr_xcrs > KVM_MAX_XCRS || guest_xcrs->flags) return -EINVAL; for (i = 0; i < guest_xcrs->nr_xcrs; i++) /* Only support XCR0 currently */ if (guest_xcrs->xcrs[i].xcr == XCR_XFEATURE_ENABLED_MASK) { r = __kvm_set_xcr(vcpu, XCR_XFEATURE_ENABLED_MASK, guest_xcrs->xcrs[i].value); break; } if (r) r = -EINVAL; return r; } /* * kvm_set_guest_paused() indicates to the guest kernel that it has been * stopped by the hypervisor. This function will be called from the host only. * EINVAL is returned when the host attempts to set the flag for a guest that * does not support pv clocks. */ static int kvm_set_guest_paused(struct kvm_vcpu *vcpu) { if (!vcpu->arch.pv_time.active) return -EINVAL; vcpu->arch.pvclock_set_guest_stopped_request = true; kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu); return 0; } static int kvm_arch_tsc_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) { int r; switch (attr->attr) { case KVM_VCPU_TSC_OFFSET: r = 0; break; default: r = -ENXIO; } return r; } static int kvm_arch_tsc_get_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) { u64 __user *uaddr = kvm_get_attr_addr(attr); int r; if (IS_ERR(uaddr)) return PTR_ERR(uaddr); switch (attr->attr) { case KVM_VCPU_TSC_OFFSET: r = -EFAULT; if (put_user(vcpu->arch.l1_tsc_offset, uaddr)) break; r = 0; break; default: r = -ENXIO; } return r; } static int kvm_arch_tsc_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) { u64 __user *uaddr = kvm_get_attr_addr(attr); struct kvm *kvm = vcpu->kvm; int r; if (IS_ERR(uaddr)) return PTR_ERR(uaddr); switch (attr->attr) { case KVM_VCPU_TSC_OFFSET: { u64 offset, tsc, ns; unsigned long flags; bool matched; r = -EFAULT; if (get_user(offset, uaddr)) break; raw_spin_lock_irqsave(&kvm->arch.tsc_write_lock, flags); matched = (vcpu->arch.virtual_tsc_khz && kvm->arch.last_tsc_khz == vcpu->arch.virtual_tsc_khz && kvm->arch.last_tsc_offset == offset); tsc = kvm_scale_tsc(rdtsc(), vcpu->arch.l1_tsc_scaling_ratio) + offset; ns = get_kvmclock_base_ns(); kvm->arch.user_set_tsc = true; __kvm_synchronize_tsc(vcpu, offset, tsc, ns, matched); raw_spin_unlock_irqrestore(&kvm->arch.tsc_write_lock, flags); r = 0; break; } default: r = -ENXIO; } return r; } static int kvm_vcpu_ioctl_device_attr(struct kvm_vcpu *vcpu, unsigned int ioctl, void __user *argp) { struct kvm_device_attr attr; int r; if (copy_from_user(&attr, argp, sizeof(attr))) return -EFAULT; if (attr.group != KVM_VCPU_TSC_CTRL) return -ENXIO; switch (ioctl) { case KVM_HAS_DEVICE_ATTR: r = kvm_arch_tsc_has_attr(vcpu, &attr); break; case KVM_GET_DEVICE_ATTR: r = kvm_arch_tsc_get_attr(vcpu, &attr); break; case KVM_SET_DEVICE_ATTR: r = kvm_arch_tsc_set_attr(vcpu, &attr); break; } return r; } static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu, struct kvm_enable_cap *cap) { if (cap->flags) return -EINVAL; switch (cap->cap) { #ifdef CONFIG_KVM_HYPERV case KVM_CAP_HYPERV_SYNIC2: if (cap->args[0]) return -EINVAL; fallthrough; case KVM_CAP_HYPERV_SYNIC: if (!irqchip_in_kernel(vcpu->kvm)) return -EINVAL; return kvm_hv_activate_synic(vcpu, cap->cap == KVM_CAP_HYPERV_SYNIC2); case KVM_CAP_HYPERV_ENLIGHTENED_VMCS: { int r; uint16_t vmcs_version; void __user *user_ptr; if (!kvm_x86_ops.nested_ops->enable_evmcs) return -ENOTTY; r = kvm_x86_ops.nested_ops->enable_evmcs(vcpu, &vmcs_version); if (!r) { user_ptr = (void __user *)(uintptr_t)cap->args[0]; if (copy_to_user(user_ptr, &vmcs_version, sizeof(vmcs_version))) r = -EFAULT; } return r; } case KVM_CAP_HYPERV_DIRECT_TLBFLUSH: if (!kvm_x86_ops.enable_l2_tlb_flush) return -ENOTTY; return static_call(kvm_x86_enable_l2_tlb_flush)(vcpu); case KVM_CAP_HYPERV_ENFORCE_CPUID: return kvm_hv_set_enforce_cpuid(vcpu, cap->args[0]); #endif case KVM_CAP_ENFORCE_PV_FEATURE_CPUID: vcpu->arch.pv_cpuid.enforce = cap->args[0]; if (vcpu->arch.pv_cpuid.enforce) kvm_update_pv_runtime(vcpu); return 0; default: return -EINVAL; } } long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { struct kvm_vcpu *vcpu = filp->private_data; void __user *argp = (void __user *)arg; int r; union { struct kvm_sregs2 *sregs2; struct kvm_lapic_state *lapic; struct kvm_xsave *xsave; struct kvm_xcrs *xcrs; void *buffer; } u; vcpu_load(vcpu); u.buffer = NULL; switch (ioctl) { case KVM_GET_LAPIC: { r = -EINVAL; if (!lapic_in_kernel(vcpu)) goto out; u.lapic = kzalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL_ACCOUNT); r = -ENOMEM; if (!u.lapic) goto out; r = kvm_vcpu_ioctl_get_lapic(vcpu, u.lapic); if (r) goto out; r = -EFAULT; if (copy_to_user(argp, u.lapic, sizeof(struct kvm_lapic_state))) goto out; r = 0; break; } case KVM_SET_LAPIC: { r = -EINVAL; if (!lapic_in_kernel(vcpu)) goto out; u.lapic = memdup_user(argp, sizeof(*u.lapic)); if (IS_ERR(u.lapic)) { r = PTR_ERR(u.lapic); goto out_nofree; } r = kvm_vcpu_ioctl_set_lapic(vcpu, u.lapic); break; } case KVM_INTERRUPT: { struct kvm_interrupt irq; r = -EFAULT; if (copy_from_user(&irq, argp, sizeof(irq))) goto out; r = kvm_vcpu_ioctl_interrupt(vcpu, &irq); break; } case KVM_NMI: { r = kvm_vcpu_ioctl_nmi(vcpu); break; } case KVM_SMI: { r = kvm_inject_smi(vcpu); break; } case KVM_SET_CPUID: { struct kvm_cpuid __user *cpuid_arg = argp; struct kvm_cpuid cpuid; r = -EFAULT; if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid))) goto out; r = kvm_vcpu_ioctl_set_cpuid(vcpu, &cpuid, cpuid_arg->entries); break; } case KVM_SET_CPUID2: { struct kvm_cpuid2 __user *cpuid_arg = argp; struct kvm_cpuid2 cpuid; r = -EFAULT; if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid))) goto out; r = kvm_vcpu_ioctl_set_cpuid2(vcpu, &cpuid, cpuid_arg->entries); break; } case KVM_GET_CPUID2: { struct kvm_cpuid2 __user *cpuid_arg = argp; struct kvm_cpuid2 cpuid; r = -EFAULT; if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid))) goto out; r = kvm_vcpu_ioctl_get_cpuid2(vcpu, &cpuid, cpuid_arg->entries); if (r) goto out; r = -EFAULT; if (copy_to_user(cpuid_arg, &cpuid, sizeof(cpuid))) goto out; r = 0; break; } case KVM_GET_MSRS: { int idx = srcu_read_lock(&vcpu->kvm->srcu); r = msr_io(vcpu, argp, do_get_msr, 1); srcu_read_unlock(&vcpu->kvm->srcu, idx); break; } case KVM_SET_MSRS: { int idx = srcu_read_lock(&vcpu->kvm->srcu); r = msr_io(vcpu, argp, do_set_msr, 0); srcu_read_unlock(&vcpu->kvm->srcu, idx); break; } case KVM_TPR_ACCESS_REPORTING: { struct kvm_tpr_access_ctl tac; r = -EFAULT; if (copy_from_user(&tac, argp, sizeof(tac))) goto out; r = vcpu_ioctl_tpr_access_reporting(vcpu, &tac); if (r) goto out; r = -EFAULT; if (copy_to_user(argp, &tac, sizeof(tac))) goto out; r = 0; break; }; case KVM_SET_VAPIC_ADDR: { struct kvm_vapic_addr va; int idx; r = -EINVAL; if (!lapic_in_kernel(vcpu)) goto out; r = -EFAULT; if (copy_from_user(&va, argp, sizeof(va))) goto out; idx = srcu_read_lock(&vcpu->kvm->srcu); r = kvm_lapic_set_vapic_addr(vcpu, va.vapic_addr); srcu_read_unlock(&vcpu->kvm->srcu, idx); break; } case KVM_X86_SETUP_MCE: { u64 mcg_cap; r = -EFAULT; if (copy_from_user(&mcg_cap, argp, sizeof(mcg_cap))) goto out; r = kvm_vcpu_ioctl_x86_setup_mce(vcpu, mcg_cap); break; } case KVM_X86_SET_MCE: { struct kvm_x86_mce mce; r = -EFAULT; if (copy_from_user(&mce, argp, sizeof(mce))) goto out; r = kvm_vcpu_ioctl_x86_set_mce(vcpu, &mce); break; } case KVM_GET_VCPU_EVENTS: { struct kvm_vcpu_events events; kvm_vcpu_ioctl_x86_get_vcpu_events(vcpu, &events); r = -EFAULT; if (copy_to_user(argp, &events, sizeof(struct kvm_vcpu_events))) break; r = 0; break; } case KVM_SET_VCPU_EVENTS: { struct kvm_vcpu_events events; r = -EFAULT; if (copy_from_user(&events, argp, sizeof(struct kvm_vcpu_events))) break; r = kvm_vcpu_ioctl_x86_set_vcpu_events(vcpu, &events); break; } case KVM_GET_DEBUGREGS: { struct kvm_debugregs dbgregs; kvm_vcpu_ioctl_x86_get_debugregs(vcpu, &dbgregs); r = -EFAULT; if (copy_to_user(argp, &dbgregs, sizeof(struct kvm_debugregs))) break; r = 0; break; } case KVM_SET_DEBUGREGS: { struct kvm_debugregs dbgregs; r = -EFAULT; if (copy_from_user(&dbgregs, argp, sizeof(struct kvm_debugregs))) break; r = kvm_vcpu_ioctl_x86_set_debugregs(vcpu, &dbgregs); break; } case KVM_GET_XSAVE: { r = -EINVAL; if (vcpu->arch.guest_fpu.uabi_size > sizeof(struct kvm_xsave)) break; u.xsave = kzalloc(sizeof(struct kvm_xsave), GFP_KERNEL_ACCOUNT); r = -ENOMEM; if (!u.xsave) break; kvm_vcpu_ioctl_x86_get_xsave(vcpu, u.xsave); r = -EFAULT; if (copy_to_user(argp, u.xsave, sizeof(struct kvm_xsave))) break; r = 0; break; } case KVM_SET_XSAVE: { int size = vcpu->arch.guest_fpu.uabi_size; u.xsave = memdup_user(argp, size); if (IS_ERR(u.xsave)) { r = PTR_ERR(u.xsave); goto out_nofree; } r = kvm_vcpu_ioctl_x86_set_xsave(vcpu, u.xsave); break; } case KVM_GET_XSAVE2: { int size = vcpu->arch.guest_fpu.uabi_size; u.xsave = kzalloc(size, GFP_KERNEL_ACCOUNT); r = -ENOMEM; if (!u.xsave) break; kvm_vcpu_ioctl_x86_get_xsave2(vcpu, u.buffer, size); r = -EFAULT; if (copy_to_user(argp, u.xsave, size)) break; r = 0; break; } case KVM_GET_XCRS: { u.xcrs = kzalloc(sizeof(struct kvm_xcrs), GFP_KERNEL_ACCOUNT); r = -ENOMEM; if (!u.xcrs) break; kvm_vcpu_ioctl_x86_get_xcrs(vcpu, u.xcrs); r = -EFAULT; if (copy_to_user(argp, u.xcrs, sizeof(struct kvm_xcrs))) break; r = 0; break; } case KVM_SET_XCRS: { u.xcrs = memdup_user(argp, sizeof(*u.xcrs)); if (IS_ERR(u.xcrs)) { r = PTR_ERR(u.xcrs); goto out_nofree; } r = kvm_vcpu_ioctl_x86_set_xcrs(vcpu, u.xcrs); break; } case KVM_SET_TSC_KHZ: { u32 user_tsc_khz; r = -EINVAL; user_tsc_khz = (u32)arg; if (kvm_caps.has_tsc_control && user_tsc_khz >= kvm_caps.max_guest_tsc_khz) goto out; if (user_tsc_khz == 0) user_tsc_khz = tsc_khz; if (!kvm_set_tsc_khz(vcpu, user_tsc_khz)) r = 0; goto out; } case KVM_GET_TSC_KHZ: { r = vcpu->arch.virtual_tsc_khz; goto out; } case KVM_KVMCLOCK_CTRL: { r = kvm_set_guest_paused(vcpu); goto out; } case KVM_ENABLE_CAP: { struct kvm_enable_cap cap; r = -EFAULT; if (copy_from_user(&cap, argp, sizeof(cap))) goto out; r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap); break; } case KVM_GET_NESTED_STATE: { struct kvm_nested_state __user *user_kvm_nested_state = argp; u32 user_data_size; r = -EINVAL; if (!kvm_x86_ops.nested_ops->get_state) break; BUILD_BUG_ON(sizeof(user_data_size) != sizeof(user_kvm_nested_state->size)); r = -EFAULT; if (get_user(user_data_size, &user_kvm_nested_state->size)) break; r = kvm_x86_ops.nested_ops->get_state(vcpu, user_kvm_nested_state, user_data_size); if (r < 0) break; if (r > user_data_size) { if (put_user(r, &user_kvm_nested_state->size)) r = -EFAULT; else r = -E2BIG; break; } r = 0; break; } case KVM_SET_NESTED_STATE: { struct kvm_nested_state __user *user_kvm_nested_state = argp; struct kvm_nested_state kvm_state; int idx; r = -EINVAL; if (!kvm_x86_ops.nested_ops->set_state) break; r = -EFAULT; if (copy_from_user(&kvm_state, user_kvm_nested_state, sizeof(kvm_state))) break; r = -EINVAL; if (kvm_state.size < sizeof(kvm_state)) break; if (kvm_state.flags & ~(KVM_STATE_NESTED_RUN_PENDING | KVM_STATE_NESTED_GUEST_MODE | KVM_STATE_NESTED_EVMCS | KVM_STATE_NESTED_MTF_PENDING | KVM_STATE_NESTED_GIF_SET)) break; /* nested_run_pending implies guest_mode. */ if ((kvm_state.flags & KVM_STATE_NESTED_RUN_PENDING) && !(kvm_state.flags & KVM_STATE_NESTED_GUEST_MODE)) break; idx = srcu_read_lock(&vcpu->kvm->srcu); r = kvm_x86_ops.nested_ops->set_state(vcpu, user_kvm_nested_state, &kvm_state); srcu_read_unlock(&vcpu->kvm->srcu, idx); break; } #ifdef CONFIG_KVM_HYPERV case KVM_GET_SUPPORTED_HV_CPUID: r = kvm_ioctl_get_supported_hv_cpuid(vcpu, argp); break; #endif #ifdef CONFIG_KVM_XEN case KVM_XEN_VCPU_GET_ATTR: { struct kvm_xen_vcpu_attr xva; r = -EFAULT; if (copy_from_user(&xva, argp, sizeof(xva))) goto out; r = kvm_xen_vcpu_get_attr(vcpu, &xva); if (!r && copy_to_user(argp, &xva, sizeof(xva))) r = -EFAULT; break; } case KVM_XEN_VCPU_SET_ATTR: { struct kvm_xen_vcpu_attr xva; r = -EFAULT; if (copy_from_user(&xva, argp, sizeof(xva))) goto out; r = kvm_xen_vcpu_set_attr(vcpu, &xva); break; } #endif case KVM_GET_SREGS2: { u.sregs2 = kzalloc(sizeof(struct kvm_sregs2), GFP_KERNEL); r = -ENOMEM; if (!u.sregs2) goto out; __get_sregs2(vcpu, u.sregs2); r = -EFAULT; if (copy_to_user(argp, u.sregs2, sizeof(struct kvm_sregs2))) goto out; r = 0; break; } case KVM_SET_SREGS2: { u.sregs2 = memdup_user(argp, sizeof(struct kvm_sregs2)); if (IS_ERR(u.sregs2)) { r = PTR_ERR(u.sregs2); u.sregs2 = NULL; goto out; } r = __set_sregs2(vcpu, u.sregs2); break; } case KVM_HAS_DEVICE_ATTR: case KVM_GET_DEVICE_ATTR: case KVM_SET_DEVICE_ATTR: r = kvm_vcpu_ioctl_device_attr(vcpu, ioctl, argp); break; default: r = -EINVAL; } out: kfree(u.buffer); out_nofree: vcpu_put(vcpu); return r; } vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) { return VM_FAULT_SIGBUS; } static int kvm_vm_ioctl_set_tss_addr(struct kvm *kvm, unsigned long addr) { int ret; if (addr > (unsigned int)(-3 * PAGE_SIZE)) return -EINVAL; ret = static_call(kvm_x86_set_tss_addr)(kvm, addr); return ret; } static int kvm_vm_ioctl_set_identity_map_addr(struct kvm *kvm, u64 ident_addr) { return static_call(kvm_x86_set_identity_map_addr)(kvm, ident_addr); } static int kvm_vm_ioctl_set_nr_mmu_pages(struct kvm *kvm, unsigned long kvm_nr_mmu_pages) { if (kvm_nr_mmu_pages < KVM_MIN_ALLOC_MMU_PAGES) return -EINVAL; mutex_lock(&kvm->slots_lock); kvm_mmu_change_mmu_pages(kvm, kvm_nr_mmu_pages); kvm->arch.n_requested_mmu_pages = kvm_nr_mmu_pages; mutex_unlock(&kvm->slots_lock); return 0; } static int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip) { struct kvm_pic *pic = kvm->arch.vpic; int r; r = 0; switch (chip->chip_id) { case KVM_IRQCHIP_PIC_MASTER: memcpy(&chip->chip.pic, &pic->pics[0], sizeof(struct kvm_pic_state)); break; case KVM_IRQCHIP_PIC_SLAVE: memcpy(&chip->chip.pic, &pic->pics[1], sizeof(struct kvm_pic_state)); break; case KVM_IRQCHIP_IOAPIC: kvm_get_ioapic(kvm, &chip->chip.ioapic); break; default: r = -EINVAL; break; } return r; } static int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip) { struct kvm_pic *pic = kvm->arch.vpic; int r; r = 0; switch (chip->chip_id) { case KVM_IRQCHIP_PIC_MASTER: spin_lock(&pic->lock); memcpy(&pic->pics[0], &chip->chip.pic, sizeof(struct kvm_pic_state)); spin_unlock(&pic->lock); break; case KVM_IRQCHIP_PIC_SLAVE: spin_lock(&pic->lock); memcpy(&pic->pics[1], &chip->chip.pic, sizeof(struct kvm_pic_state)); spin_unlock(&pic->lock); break; case KVM_IRQCHIP_IOAPIC: kvm_set_ioapic(kvm, &chip->chip.ioapic); break; default: r = -EINVAL; break; } kvm_pic_update_irq(pic); return r; } static int kvm_vm_ioctl_get_pit(struct kvm *kvm, struct kvm_pit_state *ps) { struct kvm_kpit_state *kps = &kvm->arch.vpit->pit_state; BUILD_BUG_ON(sizeof(*ps) != sizeof(kps->channels)); mutex_lock(&kps->lock); memcpy(ps, &kps->channels, sizeof(*ps)); mutex_unlock(&kps->lock); return 0; } static int kvm_vm_ioctl_set_pit(struct kvm *kvm, struct kvm_pit_state *ps) { int i; struct kvm_pit *pit = kvm->arch.vpit; mutex_lock(&pit->pit_state.lock); memcpy(&pit->pit_state.channels, ps, sizeof(*ps)); for (i = 0; i < 3; i++) kvm_pit_load_count(pit, i, ps->channels[i].count, 0); mutex_unlock(&pit->pit_state.lock); return 0; } static int kvm_vm_ioctl_get_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps) { mutex_lock(&kvm->arch.vpit->pit_state.lock); memcpy(ps->channels, &kvm->arch.vpit->pit_state.channels, sizeof(ps->channels)); ps->flags = kvm->arch.vpit->pit_state.flags; mutex_unlock(&kvm->arch.vpit->pit_state.lock); memset(&ps->reserved, 0, sizeof(ps->reserved)); return 0; } static int kvm_vm_ioctl_set_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps) { int start = 0; int i; u32 prev_legacy, cur_legacy; struct kvm_pit *pit = kvm->arch.vpit; mutex_lock(&pit->pit_state.lock); prev_legacy = pit->pit_state.flags & KVM_PIT_FLAGS_HPET_LEGACY; cur_legacy = ps->flags & KVM_PIT_FLAGS_HPET_LEGACY; if (!prev_legacy && cur_legacy) start = 1; memcpy(&pit->pit_state.channels, &ps->channels, sizeof(pit->pit_state.channels)); pit->pit_state.flags = ps->flags; for (i = 0; i < 3; i++) kvm_pit_load_count(pit, i, pit->pit_state.channels[i].count, start && i == 0); mutex_unlock(&pit->pit_state.lock); return 0; } static int kvm_vm_ioctl_reinject(struct kvm *kvm, struct kvm_reinject_control *control) { struct kvm_pit *pit = kvm->arch.vpit; /* pit->pit_state.lock was overloaded to prevent userspace from getting * an inconsistent state after running multiple KVM_REINJECT_CONTROL * ioctls in parallel. Use a separate lock if that ioctl isn't rare. */ mutex_lock(&pit->pit_state.lock); kvm_pit_set_reinject(pit, control->pit_reinject); mutex_unlock(&pit->pit_state.lock); return 0; } void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) { /* * Flush all CPUs' dirty log buffers to the dirty_bitmap. Called * before reporting dirty_bitmap to userspace. KVM flushes the buffers * on all VM-Exits, thus we only need to kick running vCPUs to force a * VM-Exit. */ struct kvm_vcpu *vcpu; unsigned long i; if (!kvm_x86_ops.cpu_dirty_log_size) return; kvm_for_each_vcpu(i, vcpu, kvm) kvm_vcpu_kick(vcpu); } int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_event, bool line_status) { if (!irqchip_in_kernel(kvm)) return -ENXIO; irq_event->status = kvm_set_irq(kvm, KVM_USERSPACE_IRQ_SOURCE_ID, irq_event->irq, irq_event->level, line_status); return 0; } int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) { int r; if (cap->flags) return -EINVAL; switch (cap->cap) { case KVM_CAP_DISABLE_QUIRKS2: r = -EINVAL; if (cap->args[0] & ~KVM_X86_VALID_QUIRKS) break; fallthrough; case KVM_CAP_DISABLE_QUIRKS: kvm->arch.disabled_quirks = cap->args[0]; r = 0; break; case KVM_CAP_SPLIT_IRQCHIP: { mutex_lock(&kvm->lock); r = -EINVAL; if (cap->args[0] > MAX_NR_RESERVED_IOAPIC_PINS) goto split_irqchip_unlock; r = -EEXIST; if (irqchip_in_kernel(kvm)) goto split_irqchip_unlock; if (kvm->created_vcpus) goto split_irqchip_unlock; r = kvm_setup_empty_irq_routing(kvm); if (r) goto split_irqchip_unlock; /* Pairs with irqchip_in_kernel. */ smp_wmb(); kvm->arch.irqchip_mode = KVM_IRQCHIP_SPLIT; kvm->arch.nr_reserved_ioapic_pins = cap->args[0]; kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_ABSENT); r = 0; split_irqchip_unlock: mutex_unlock(&kvm->lock); break; } case KVM_CAP_X2APIC_API: r = -EINVAL; if (cap->args[0] & ~KVM_X2APIC_API_VALID_FLAGS) break; if (cap->args[0] & KVM_X2APIC_API_USE_32BIT_IDS) kvm->arch.x2apic_format = true; if (cap->args[0] & KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK) kvm->arch.x2apic_broadcast_quirk_disabled = true; r = 0; break; case KVM_CAP_X86_DISABLE_EXITS: r = -EINVAL; if (cap->args[0] & ~KVM_X86_DISABLE_VALID_EXITS) break; if (cap->args[0] & KVM_X86_DISABLE_EXITS_PAUSE) kvm->arch.pause_in_guest = true; #define SMT_RSB_MSG "This processor is affected by the Cross-Thread Return Predictions vulnerability. " \ "KVM_CAP_X86_DISABLE_EXITS should only be used with SMT disabled or trusted guests." if (!mitigate_smt_rsb) { if (boot_cpu_has_bug(X86_BUG_SMT_RSB) && cpu_smt_possible() && (cap->args[0] & ~KVM_X86_DISABLE_EXITS_PAUSE)) pr_warn_once(SMT_RSB_MSG); if ((cap->args[0] & KVM_X86_DISABLE_EXITS_MWAIT) && kvm_can_mwait_in_guest()) kvm->arch.mwait_in_guest = true; if (cap->args[0] & KVM_X86_DISABLE_EXITS_HLT) kvm->arch.hlt_in_guest = true; if (cap->args[0] & KVM_X86_DISABLE_EXITS_CSTATE) kvm->arch.cstate_in_guest = true; } r = 0; break; case KVM_CAP_MSR_PLATFORM_INFO: kvm->arch.guest_can_read_msr_platform_info = cap->args[0]; r = 0; break; case KVM_CAP_EXCEPTION_PAYLOAD: kvm->arch.exception_payload_enabled = cap->args[0]; r = 0; break; case KVM_CAP_X86_TRIPLE_FAULT_EVENT: kvm->arch.triple_fault_event = cap->args[0]; r = 0; break; case KVM_CAP_X86_USER_SPACE_MSR: r = -EINVAL; if (cap->args[0] & ~KVM_MSR_EXIT_REASON_VALID_MASK) break; kvm->arch.user_space_msr_mask = cap->args[0]; r = 0; break; case KVM_CAP_X86_BUS_LOCK_EXIT: r = -EINVAL; if (cap->args[0] & ~KVM_BUS_LOCK_DETECTION_VALID_MODE) break; if ((cap->args[0] & KVM_BUS_LOCK_DETECTION_OFF) && (cap->args[0] & KVM_BUS_LOCK_DETECTION_EXIT)) break; if (kvm_caps.has_bus_lock_exit && cap->args[0] & KVM_BUS_LOCK_DETECTION_EXIT) kvm->arch.bus_lock_detection_enabled = true; r = 0; break; #ifdef CONFIG_X86_SGX_KVM case KVM_CAP_SGX_ATTRIBUTE: { unsigned long allowed_attributes = 0; r = sgx_set_attribute(&allowed_attributes, cap->args[0]); if (r) break; /* KVM only supports the PROVISIONKEY privileged attribute. */ if ((allowed_attributes & SGX_ATTR_PROVISIONKEY) && !(allowed_attributes & ~SGX_ATTR_PROVISIONKEY)) kvm->arch.sgx_provisioning_allowed = true; else r = -EINVAL; break; } #endif case KVM_CAP_VM_COPY_ENC_CONTEXT_FROM: r = -EINVAL; if (!kvm_x86_ops.vm_copy_enc_context_from) break; r = static_call(kvm_x86_vm_copy_enc_context_from)(kvm, cap->args[0]); break; case KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM: r = -EINVAL; if (!kvm_x86_ops.vm_move_enc_context_from) break; r = static_call(kvm_x86_vm_move_enc_context_from)(kvm, cap->args[0]); break; case KVM_CAP_EXIT_HYPERCALL: if (cap->args[0] & ~KVM_EXIT_HYPERCALL_VALID_MASK) { r = -EINVAL; break; } kvm->arch.hypercall_exit_enabled = cap->args[0]; r = 0; break; case KVM_CAP_EXIT_ON_EMULATION_FAILURE: r = -EINVAL; if (cap->args[0] & ~1) break; kvm->arch.exit_on_emulation_error = cap->args[0]; r = 0; break; case KVM_CAP_PMU_CAPABILITY: r = -EINVAL; if (!enable_pmu || (cap->args[0] & ~KVM_CAP_PMU_VALID_MASK)) break; mutex_lock(&kvm->lock); if (!kvm->created_vcpus) { kvm->arch.enable_pmu = !(cap->args[0] & KVM_PMU_CAP_DISABLE); r = 0; } mutex_unlock(&kvm->lock); break; case KVM_CAP_MAX_VCPU_ID: r = -EINVAL; if (cap->args[0] > KVM_MAX_VCPU_IDS) break; mutex_lock(&kvm->lock); if (kvm->arch.max_vcpu_ids == cap->args[0]) { r = 0; } else if (!kvm->arch.max_vcpu_ids) { kvm->arch.max_vcpu_ids = cap->args[0]; r = 0; } mutex_unlock(&kvm->lock); break; case KVM_CAP_X86_NOTIFY_VMEXIT: r = -EINVAL; if ((u32)cap->args[0] & ~KVM_X86_NOTIFY_VMEXIT_VALID_BITS) break; if (!kvm_caps.has_notify_vmexit) break; if (!((u32)cap->args[0] & KVM_X86_NOTIFY_VMEXIT_ENABLED)) break; mutex_lock(&kvm->lock); if (!kvm->created_vcpus) { kvm->arch.notify_window = cap->args[0] >> 32; kvm->arch.notify_vmexit_flags = (u32)cap->args[0]; r = 0; } mutex_unlock(&kvm->lock); break; case KVM_CAP_VM_DISABLE_NX_HUGE_PAGES: r = -EINVAL; /* * Since the risk of disabling NX hugepages is a guest crashing * the system, ensure the userspace process has permission to * reboot the system. * * Note that unlike the reboot() syscall, the process must have * this capability in the root namespace because exposing * /dev/kvm into a container does not limit the scope of the * iTLB multihit bug to that container. In other words, * this must use capable(), not ns_capable(). */ if (!capable(CAP_SYS_BOOT)) { r = -EPERM; break; } if (cap->args[0]) break; mutex_lock(&kvm->lock); if (!kvm->created_vcpus) { kvm->arch.disable_nx_huge_pages = true; r = 0; } mutex_unlock(&kvm->lock); break; default: r = -EINVAL; break; } return r; } static struct kvm_x86_msr_filter *kvm_alloc_msr_filter(bool default_allow) { struct kvm_x86_msr_filter *msr_filter; msr_filter = kzalloc(sizeof(*msr_filter), GFP_KERNEL_ACCOUNT); if (!msr_filter) return NULL; msr_filter->default_allow = default_allow; return msr_filter; } static void kvm_free_msr_filter(struct kvm_x86_msr_filter *msr_filter) { u32 i; if (!msr_filter) return; for (i = 0; i < msr_filter->count; i++) kfree(msr_filter->ranges[i].bitmap); kfree(msr_filter); } static int kvm_add_msr_filter(struct kvm_x86_msr_filter *msr_filter, struct kvm_msr_filter_range *user_range) { unsigned long *bitmap; size_t bitmap_size; if (!user_range->nmsrs) return 0; if (user_range->flags & ~KVM_MSR_FILTER_RANGE_VALID_MASK) return -EINVAL; if (!user_range->flags) return -EINVAL; bitmap_size = BITS_TO_LONGS(user_range->nmsrs) * sizeof(long); if (!bitmap_size || bitmap_size > KVM_MSR_FILTER_MAX_BITMAP_SIZE) return -EINVAL; bitmap = memdup_user((__user u8*)user_range->bitmap, bitmap_size); if (IS_ERR(bitmap)) return PTR_ERR(bitmap); msr_filter->ranges[msr_filter->count] = (struct msr_bitmap_range) { .flags = user_range->flags, .base = user_range->base, .nmsrs = user_range->nmsrs, .bitmap = bitmap, }; msr_filter->count++; return 0; } static int kvm_vm_ioctl_set_msr_filter(struct kvm *kvm, struct kvm_msr_filter *filter) { struct kvm_x86_msr_filter *new_filter, *old_filter; bool default_allow; bool empty = true; int r; u32 i; if (filter->flags & ~KVM_MSR_FILTER_VALID_MASK) return -EINVAL; for (i = 0; i < ARRAY_SIZE(filter->ranges); i++) empty &= !filter->ranges[i].nmsrs; default_allow = !(filter->flags & KVM_MSR_FILTER_DEFAULT_DENY); if (empty && !default_allow) return -EINVAL; new_filter = kvm_alloc_msr_filter(default_allow); if (!new_filter) return -ENOMEM; for (i = 0; i < ARRAY_SIZE(filter->ranges); i++) { r = kvm_add_msr_filter(new_filter, &filter->ranges[i]); if (r) { kvm_free_msr_filter(new_filter); return r; } } mutex_lock(&kvm->lock); old_filter = rcu_replace_pointer(kvm->arch.msr_filter, new_filter, mutex_is_locked(&kvm->lock)); mutex_unlock(&kvm->lock); synchronize_srcu(&kvm->srcu); kvm_free_msr_filter(old_filter); kvm_make_all_cpus_request(kvm, KVM_REQ_MSR_FILTER_CHANGED); return 0; } #ifdef CONFIG_KVM_COMPAT /* for KVM_X86_SET_MSR_FILTER */ struct kvm_msr_filter_range_compat { __u32 flags; __u32 nmsrs; __u32 base; __u32 bitmap; }; struct kvm_msr_filter_compat { __u32 flags; struct kvm_msr_filter_range_compat ranges[KVM_MSR_FILTER_MAX_RANGES]; }; #define KVM_X86_SET_MSR_FILTER_COMPAT _IOW(KVMIO, 0xc6, struct kvm_msr_filter_compat) long kvm_arch_vm_compat_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { void __user *argp = (void __user *)arg; struct kvm *kvm = filp->private_data; long r = -ENOTTY; switch (ioctl) { case KVM_X86_SET_MSR_FILTER_COMPAT: { struct kvm_msr_filter __user *user_msr_filter = argp; struct kvm_msr_filter_compat filter_compat; struct kvm_msr_filter filter; int i; if (copy_from_user(&filter_compat, user_msr_filter, sizeof(filter_compat))) return -EFAULT; filter.flags = filter_compat.flags; for (i = 0; i < ARRAY_SIZE(filter.ranges); i++) { struct kvm_msr_filter_range_compat *cr; cr = &filter_compat.ranges[i]; filter.ranges[i] = (struct kvm_msr_filter_range) { .flags = cr->flags, .nmsrs = cr->nmsrs, .base = cr->base, .bitmap = (__u8 *)(ulong)cr->bitmap, }; } r = kvm_vm_ioctl_set_msr_filter(kvm, &filter); break; } } return r; } #endif #ifdef CONFIG_HAVE_KVM_PM_NOTIFIER static int kvm_arch_suspend_notifier(struct kvm *kvm) { struct kvm_vcpu *vcpu; unsigned long i; int ret = 0; mutex_lock(&kvm->lock); kvm_for_each_vcpu(i, vcpu, kvm) { if (!vcpu->arch.pv_time.active) continue; ret = kvm_set_guest_paused(vcpu); if (ret) { kvm_err("Failed to pause guest VCPU%d: %d\n", vcpu->vcpu_id, ret); break; } } mutex_unlock(&kvm->lock); return ret ? NOTIFY_BAD : NOTIFY_DONE; } int kvm_arch_pm_notifier(struct kvm *kvm, unsigned long state) { switch (state) { case PM_HIBERNATION_PREPARE: case PM_SUSPEND_PREPARE: return kvm_arch_suspend_notifier(kvm); } return NOTIFY_DONE; } #endif /* CONFIG_HAVE_KVM_PM_NOTIFIER */ static int kvm_vm_ioctl_get_clock(struct kvm *kvm, void __user *argp) { struct kvm_clock_data data = { 0 }; get_kvmclock(kvm, &data); if (copy_to_user(argp, &data, sizeof(data))) return -EFAULT; return 0; } static int kvm_vm_ioctl_set_clock(struct kvm *kvm, void __user *argp) { struct kvm_arch *ka = &kvm->arch; struct kvm_clock_data data; u64 now_raw_ns; if (copy_from_user(&data, argp, sizeof(data))) return -EFAULT; /* * Only KVM_CLOCK_REALTIME is used, but allow passing the * result of KVM_GET_CLOCK back to KVM_SET_CLOCK. */ if (data.flags & ~KVM_CLOCK_VALID_FLAGS) return -EINVAL; kvm_hv_request_tsc_page_update(kvm); kvm_start_pvclock_update(kvm); pvclock_update_vm_gtod_copy(kvm); /* * This pairs with kvm_guest_time_update(): when masterclock is * in use, we use master_kernel_ns + kvmclock_offset to set * unsigned 'system_time' so if we use get_kvmclock_ns() (which * is slightly ahead) here we risk going negative on unsigned * 'system_time' when 'data.clock' is very small. */ if (data.flags & KVM_CLOCK_REALTIME) { u64 now_real_ns = ktime_get_real_ns(); /* * Avoid stepping the kvmclock backwards. */ if (now_real_ns > data.realtime) data.clock += now_real_ns - data.realtime; } if (ka->use_master_clock) now_raw_ns = ka->master_kernel_ns; else now_raw_ns = get_kvmclock_base_ns(); ka->kvmclock_offset = data.clock - now_raw_ns; kvm_end_pvclock_update(kvm); return 0; } int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { struct kvm *kvm = filp->private_data; void __user *argp = (void __user *)arg; int r = -ENOTTY; /* * This union makes it completely explicit to gcc-3.x * that these two variables' stack usage should be * combined, not added together. */ union { struct kvm_pit_state ps; struct kvm_pit_state2 ps2; struct kvm_pit_config pit_config; } u; switch (ioctl) { case KVM_SET_TSS_ADDR: r = kvm_vm_ioctl_set_tss_addr(kvm, arg); break; case KVM_SET_IDENTITY_MAP_ADDR: { u64 ident_addr; mutex_lock(&kvm->lock); r = -EINVAL; if (kvm->created_vcpus) goto set_identity_unlock; r = -EFAULT; if (copy_from_user(&ident_addr, argp, sizeof(ident_addr))) goto set_identity_unlock; r = kvm_vm_ioctl_set_identity_map_addr(kvm, ident_addr); set_identity_unlock: mutex_unlock(&kvm->lock); break; } case KVM_SET_NR_MMU_PAGES: r = kvm_vm_ioctl_set_nr_mmu_pages(kvm, arg); break; case KVM_CREATE_IRQCHIP: { mutex_lock(&kvm->lock); r = -EEXIST; if (irqchip_in_kernel(kvm)) goto create_irqchip_unlock; r = -EINVAL; if (kvm->created_vcpus) goto create_irqchip_unlock; r = kvm_pic_init(kvm); if (r) goto create_irqchip_unlock; r = kvm_ioapic_init(kvm); if (r) { kvm_pic_destroy(kvm); goto create_irqchip_unlock; } r = kvm_setup_default_irq_routing(kvm); if (r) { kvm_ioapic_destroy(kvm); kvm_pic_destroy(kvm); goto create_irqchip_unlock; } /* Write kvm->irq_routing before enabling irqchip_in_kernel. */ smp_wmb(); kvm->arch.irqchip_mode = KVM_IRQCHIP_KERNEL; kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_ABSENT); create_irqchip_unlock: mutex_unlock(&kvm->lock); break; } case KVM_CREATE_PIT: u.pit_config.flags = KVM_PIT_SPEAKER_DUMMY; goto create_pit; case KVM_CREATE_PIT2: r = -EFAULT; if (copy_from_user(&u.pit_config, argp, sizeof(struct kvm_pit_config))) goto out; create_pit: mutex_lock(&kvm->lock); r = -EEXIST; if (kvm->arch.vpit) goto create_pit_unlock; r = -ENOMEM; kvm->arch.vpit = kvm_create_pit(kvm, u.pit_config.flags); if (kvm->arch.vpit) r = 0; create_pit_unlock: mutex_unlock(&kvm->lock); break; case KVM_GET_IRQCHIP: { /* 0: PIC master, 1: PIC slave, 2: IOAPIC */ struct kvm_irqchip *chip; chip = memdup_user(argp, sizeof(*chip)); if (IS_ERR(chip)) { r = PTR_ERR(chip); goto out; } r = -ENXIO; if (!irqchip_kernel(kvm)) goto get_irqchip_out; r = kvm_vm_ioctl_get_irqchip(kvm, chip); if (r) goto get_irqchip_out; r = -EFAULT; if (copy_to_user(argp, chip, sizeof(*chip))) goto get_irqchip_out; r = 0; get_irqchip_out: kfree(chip); break; } case KVM_SET_IRQCHIP: { /* 0: PIC master, 1: PIC slave, 2: IOAPIC */ struct kvm_irqchip *chip; chip = memdup_user(argp, sizeof(*chip)); if (IS_ERR(chip)) { r = PTR_ERR(chip); goto out; } r = -ENXIO; if (!irqchip_kernel(kvm)) goto set_irqchip_out; r = kvm_vm_ioctl_set_irqchip(kvm, chip); set_irqchip_out: kfree(chip); break; } case KVM_GET_PIT: { r = -EFAULT; if (copy_from_user(&u.ps, argp, sizeof(struct kvm_pit_state))) goto out; r = -ENXIO; if (!kvm->arch.vpit) goto out; r = kvm_vm_ioctl_get_pit(kvm, &u.ps); if (r) goto out; r = -EFAULT; if (copy_to_user(argp, &u.ps, sizeof(struct kvm_pit_state))) goto out; r = 0; break; } case KVM_SET_PIT: { r = -EFAULT; if (copy_from_user(&u.ps, argp, sizeof(u.ps))) goto out; mutex_lock(&kvm->lock); r = -ENXIO; if (!kvm->arch.vpit) goto set_pit_out; r = kvm_vm_ioctl_set_pit(kvm, &u.ps); set_pit_out: mutex_unlock(&kvm->lock); break; } case KVM_GET_PIT2: { r = -ENXIO; if (!kvm->arch.vpit) goto out; r = kvm_vm_ioctl_get_pit2(kvm, &u.ps2); if (r) goto out; r = -EFAULT; if (copy_to_user(argp, &u.ps2, sizeof(u.ps2))) goto out; r = 0; break; } case KVM_SET_PIT2: { r = -EFAULT; if (copy_from_user(&u.ps2, argp, sizeof(u.ps2))) goto out; mutex_lock(&kvm->lock); r = -ENXIO; if (!kvm->arch.vpit) goto set_pit2_out; r = kvm_vm_ioctl_set_pit2(kvm, &u.ps2); set_pit2_out: mutex_unlock(&kvm->lock); break; } case KVM_REINJECT_CONTROL: { struct kvm_reinject_control control; r = -EFAULT; if (copy_from_user(&control, argp, sizeof(control))) goto out; r = -ENXIO; if (!kvm->arch.vpit) goto out; r = kvm_vm_ioctl_reinject(kvm, &control); break; } case KVM_SET_BOOT_CPU_ID: r = 0; mutex_lock(&kvm->lock); if (kvm->created_vcpus) r = -EBUSY; else kvm->arch.bsp_vcpu_id = arg; mutex_unlock(&kvm->lock); break; #ifdef CONFIG_KVM_XEN case KVM_XEN_HVM_CONFIG: { struct kvm_xen_hvm_config xhc; r = -EFAULT; if (copy_from_user(&xhc, argp, sizeof(xhc))) goto out; r = kvm_xen_hvm_config(kvm, &xhc); break; } case KVM_XEN_HVM_GET_ATTR: { struct kvm_xen_hvm_attr xha; r = -EFAULT; if (copy_from_user(&xha, argp, sizeof(xha))) goto out; r = kvm_xen_hvm_get_attr(kvm, &xha); if (!r && copy_to_user(argp, &xha, sizeof(xha))) r = -EFAULT; break; } case KVM_XEN_HVM_SET_ATTR: { struct kvm_xen_hvm_attr xha; r = -EFAULT; if (copy_from_user(&xha, argp, sizeof(xha))) goto out; r = kvm_xen_hvm_set_attr(kvm, &xha); break; } case KVM_XEN_HVM_EVTCHN_SEND: { struct kvm_irq_routing_xen_evtchn uxe; r = -EFAULT; if (copy_from_user(&uxe, argp, sizeof(uxe))) goto out; r = kvm_xen_hvm_evtchn_send(kvm, &uxe); break; } #endif case KVM_SET_CLOCK: r = kvm_vm_ioctl_set_clock(kvm, argp); break; case KVM_GET_CLOCK: r = kvm_vm_ioctl_get_clock(kvm, argp); break; case KVM_SET_TSC_KHZ: { u32 user_tsc_khz; r = -EINVAL; user_tsc_khz = (u32)arg; if (kvm_caps.has_tsc_control && user_tsc_khz >= kvm_caps.max_guest_tsc_khz) goto out; if (user_tsc_khz == 0) user_tsc_khz = tsc_khz; WRITE_ONCE(kvm->arch.default_tsc_khz, user_tsc_khz); r = 0; goto out; } case KVM_GET_TSC_KHZ: { r = READ_ONCE(kvm->arch.default_tsc_khz); goto out; } case KVM_MEMORY_ENCRYPT_OP: { r = -ENOTTY; if (!kvm_x86_ops.mem_enc_ioctl) goto out; r = static_call(kvm_x86_mem_enc_ioctl)(kvm, argp); break; } case KVM_MEMORY_ENCRYPT_REG_REGION: { struct kvm_enc_region region; r = -EFAULT; if (copy_from_user(®ion, argp, sizeof(region))) goto out; r = -ENOTTY; if (!kvm_x86_ops.mem_enc_register_region) goto out; r = static_call(kvm_x86_mem_enc_register_region)(kvm, ®ion); break; } case KVM_MEMORY_ENCRYPT_UNREG_REGION: { struct kvm_enc_region region; r = -EFAULT; if (copy_from_user(®ion, argp, sizeof(region))) goto out; r = -ENOTTY; if (!kvm_x86_ops.mem_enc_unregister_region) goto out; r = static_call(kvm_x86_mem_enc_unregister_region)(kvm, ®ion); break; } #ifdef CONFIG_KVM_HYPERV case KVM_HYPERV_EVENTFD: { struct kvm_hyperv_eventfd hvevfd; r = -EFAULT; if (copy_from_user(&hvevfd, argp, sizeof(hvevfd))) goto out; r = kvm_vm_ioctl_hv_eventfd(kvm, &hvevfd); break; } #endif case KVM_SET_PMU_EVENT_FILTER: r = kvm_vm_ioctl_set_pmu_event_filter(kvm, argp); break; case KVM_X86_SET_MSR_FILTER: { struct kvm_msr_filter __user *user_msr_filter = argp; struct kvm_msr_filter filter; if (copy_from_user(&filter, user_msr_filter, sizeof(filter))) return -EFAULT; r = kvm_vm_ioctl_set_msr_filter(kvm, &filter); break; } default: r = -ENOTTY; } out: return r; } static void kvm_probe_feature_msr(u32 msr_index) { struct kvm_msr_entry msr = { .index = msr_index, }; if (kvm_get_msr_feature(&msr)) return; msr_based_features[num_msr_based_features++] = msr_index; } static void kvm_probe_msr_to_save(u32 msr_index) { u32 dummy[2]; if (rdmsr_safe(msr_index, &dummy[0], &dummy[1])) return; /* * Even MSRs that are valid in the host may not be exposed to guests in * some cases. */ switch (msr_index) { case MSR_IA32_BNDCFGS: if (!kvm_mpx_supported()) return; break; case MSR_TSC_AUX: if (!kvm_cpu_cap_has(X86_FEATURE_RDTSCP) && !kvm_cpu_cap_has(X86_FEATURE_RDPID)) return; break; case MSR_IA32_UMWAIT_CONTROL: if (!kvm_cpu_cap_has(X86_FEATURE_WAITPKG)) return; break; case MSR_IA32_RTIT_CTL: case MSR_IA32_RTIT_STATUS: if (!kvm_cpu_cap_has(X86_FEATURE_INTEL_PT)) return; break; case MSR_IA32_RTIT_CR3_MATCH: if (!kvm_cpu_cap_has(X86_FEATURE_INTEL_PT) || !intel_pt_validate_hw_cap(PT_CAP_cr3_filtering)) return; break; case MSR_IA32_RTIT_OUTPUT_BASE: case MSR_IA32_RTIT_OUTPUT_MASK: if (!kvm_cpu_cap_has(X86_FEATURE_INTEL_PT) || (!intel_pt_validate_hw_cap(PT_CAP_topa_output) && !intel_pt_validate_hw_cap(PT_CAP_single_range_output))) return; break; case MSR_IA32_RTIT_ADDR0_A ... MSR_IA32_RTIT_ADDR3_B: if (!kvm_cpu_cap_has(X86_FEATURE_INTEL_PT) || (msr_index - MSR_IA32_RTIT_ADDR0_A >= intel_pt_validate_hw_cap(PT_CAP_num_address_ranges) * 2)) return; break; case MSR_ARCH_PERFMON_PERFCTR0 ... MSR_ARCH_PERFMON_PERFCTR_MAX: if (msr_index - MSR_ARCH_PERFMON_PERFCTR0 >= kvm_pmu_cap.num_counters_gp) return; break; case MSR_ARCH_PERFMON_EVENTSEL0 ... MSR_ARCH_PERFMON_EVENTSEL_MAX: if (msr_index - MSR_ARCH_PERFMON_EVENTSEL0 >= kvm_pmu_cap.num_counters_gp) return; break; case MSR_ARCH_PERFMON_FIXED_CTR0 ... MSR_ARCH_PERFMON_FIXED_CTR_MAX: if (msr_index - MSR_ARCH_PERFMON_FIXED_CTR0 >= kvm_pmu_cap.num_counters_fixed) return; break; case MSR_AMD64_PERF_CNTR_GLOBAL_CTL: case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS: case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR: if (!kvm_cpu_cap_has(X86_FEATURE_PERFMON_V2)) return; break; case MSR_IA32_XFD: case MSR_IA32_XFD_ERR: if (!kvm_cpu_cap_has(X86_FEATURE_XFD)) return; break; case MSR_IA32_TSX_CTRL: if (!(kvm_get_arch_capabilities() & ARCH_CAP_TSX_CTRL_MSR)) return; break; default: break; } msrs_to_save[num_msrs_to_save++] = msr_index; } static void kvm_init_msr_lists(void) { unsigned i; BUILD_BUG_ON_MSG(KVM_PMC_MAX_FIXED != 3, "Please update the fixed PMCs in msrs_to_save_pmu[]"); num_msrs_to_save = 0; num_emulated_msrs = 0; num_msr_based_features = 0; for (i = 0; i < ARRAY_SIZE(msrs_to_save_base); i++) kvm_probe_msr_to_save(msrs_to_save_base[i]); if (enable_pmu) { for (i = 0; i < ARRAY_SIZE(msrs_to_save_pmu); i++) kvm_probe_msr_to_save(msrs_to_save_pmu[i]); } for (i = 0; i < ARRAY_SIZE(emulated_msrs_all); i++) { if (!static_call(kvm_x86_has_emulated_msr)(NULL, emulated_msrs_all[i])) continue; emulated_msrs[num_emulated_msrs++] = emulated_msrs_all[i]; } for (i = KVM_FIRST_EMULATED_VMX_MSR; i <= KVM_LAST_EMULATED_VMX_MSR; i++) kvm_probe_feature_msr(i); for (i = 0; i < ARRAY_SIZE(msr_based_features_all_except_vmx); i++) kvm_probe_feature_msr(msr_based_features_all_except_vmx[i]); } static int vcpu_mmio_write(struct kvm_vcpu *vcpu, gpa_t addr, int len, const void *v) { int handled = 0; int n; do { n = min(len, 8); if (!(lapic_in_kernel(vcpu) && !kvm_iodevice_write(vcpu, &vcpu->arch.apic->dev, addr, n, v)) && kvm_io_bus_write(vcpu, KVM_MMIO_BUS, addr, n, v)) break; handled += n; addr += n; len -= n; v += n; } while (len); return handled; } static int vcpu_mmio_read(struct kvm_vcpu *vcpu, gpa_t addr, int len, void *v) { int handled = 0; int n; do { n = min(len, 8); if (!(lapic_in_kernel(vcpu) && !kvm_iodevice_read(vcpu, &vcpu->arch.apic->dev, addr, n, v)) && kvm_io_bus_read(vcpu, KVM_MMIO_BUS, addr, n, v)) break; trace_kvm_mmio(KVM_TRACE_MMIO_READ, n, addr, v); handled += n; addr += n; len -= n; v += n; } while (len); return handled; } void kvm_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg) { static_call(kvm_x86_set_segment)(vcpu, var, seg); } void kvm_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg) { static_call(kvm_x86_get_segment)(vcpu, var, seg); } gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u64 access, struct x86_exception *exception) { struct kvm_mmu *mmu = vcpu->arch.mmu; gpa_t t_gpa; BUG_ON(!mmu_is_nested(vcpu)); /* NPT walks are always user-walks */ access |= PFERR_USER_MASK; t_gpa = mmu->gva_to_gpa(vcpu, mmu, gpa, access, exception); return t_gpa; } gpa_t kvm_mmu_gva_to_gpa_read(struct kvm_vcpu *vcpu, gva_t gva, struct x86_exception *exception) { struct kvm_mmu *mmu = vcpu->arch.walk_mmu; u64 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0; return mmu->gva_to_gpa(vcpu, mmu, gva, access, exception); } EXPORT_SYMBOL_GPL(kvm_mmu_gva_to_gpa_read); gpa_t kvm_mmu_gva_to_gpa_write(struct kvm_vcpu *vcpu, gva_t gva, struct x86_exception *exception) { struct kvm_mmu *mmu = vcpu->arch.walk_mmu; u64 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0; access |= PFERR_WRITE_MASK; return mmu->gva_to_gpa(vcpu, mmu, gva, access, exception); } EXPORT_SYMBOL_GPL(kvm_mmu_gva_to_gpa_write); /* uses this to access any guest's mapped memory without checking CPL */ gpa_t kvm_mmu_gva_to_gpa_system(struct kvm_vcpu *vcpu, gva_t gva, struct x86_exception *exception) { struct kvm_mmu *mmu = vcpu->arch.walk_mmu; return mmu->gva_to_gpa(vcpu, mmu, gva, 0, exception); } static int kvm_read_guest_virt_helper(gva_t addr, void *val, unsigned int bytes, struct kvm_vcpu *vcpu, u64 access, struct x86_exception *exception) { struct kvm_mmu *mmu = vcpu->arch.walk_mmu; void *data = val; int r = X86EMUL_CONTINUE; while (bytes) { gpa_t gpa = mmu->gva_to_gpa(vcpu, mmu, addr, access, exception); unsigned offset = addr & (PAGE_SIZE-1); unsigned toread = min(bytes, (unsigned)PAGE_SIZE - offset); int ret; if (gpa == INVALID_GPA) return X86EMUL_PROPAGATE_FAULT; ret = kvm_vcpu_read_guest_page(vcpu, gpa >> PAGE_SHIFT, data, offset, toread); if (ret < 0) { r = X86EMUL_IO_NEEDED; goto out; } bytes -= toread; data += toread; addr += toread; } out: return r; } /* used for instruction fetching */ static int kvm_fetch_guest_virt(struct x86_emulate_ctxt *ctxt, gva_t addr, void *val, unsigned int bytes, struct x86_exception *exception) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); struct kvm_mmu *mmu = vcpu->arch.walk_mmu; u64 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0; unsigned offset; int ret; /* Inline kvm_read_guest_virt_helper for speed. */ gpa_t gpa = mmu->gva_to_gpa(vcpu, mmu, addr, access|PFERR_FETCH_MASK, exception); if (unlikely(gpa == INVALID_GPA)) return X86EMUL_PROPAGATE_FAULT; offset = addr & (PAGE_SIZE-1); if (WARN_ON(offset + bytes > PAGE_SIZE)) bytes = (unsigned)PAGE_SIZE - offset; ret = kvm_vcpu_read_guest_page(vcpu, gpa >> PAGE_SHIFT, val, offset, bytes); if (unlikely(ret < 0)) return X86EMUL_IO_NEEDED; return X86EMUL_CONTINUE; } int kvm_read_guest_virt(struct kvm_vcpu *vcpu, gva_t addr, void *val, unsigned int bytes, struct x86_exception *exception) { u64 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0; /* * FIXME: this should call handle_emulation_failure if X86EMUL_IO_NEEDED * is returned, but our callers are not ready for that and they blindly * call kvm_inject_page_fault. Ensure that they at least do not leak * uninitialized kernel stack memory into cr2 and error code. */ memset(exception, 0, sizeof(*exception)); return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, access, exception); } EXPORT_SYMBOL_GPL(kvm_read_guest_virt); static int emulator_read_std(struct x86_emulate_ctxt *ctxt, gva_t addr, void *val, unsigned int bytes, struct x86_exception *exception, bool system) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); u64 access = 0; if (system) access |= PFERR_IMPLICIT_ACCESS; else if (static_call(kvm_x86_get_cpl)(vcpu) == 3) access |= PFERR_USER_MASK; return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, access, exception); } static int kvm_write_guest_virt_helper(gva_t addr, void *val, unsigned int bytes, struct kvm_vcpu *vcpu, u64 access, struct x86_exception *exception) { struct kvm_mmu *mmu = vcpu->arch.walk_mmu; void *data = val; int r = X86EMUL_CONTINUE; while (bytes) { gpa_t gpa = mmu->gva_to_gpa(vcpu, mmu, addr, access, exception); unsigned offset = addr & (PAGE_SIZE-1); unsigned towrite = min(bytes, (unsigned)PAGE_SIZE - offset); int ret; if (gpa == INVALID_GPA) return X86EMUL_PROPAGATE_FAULT; ret = kvm_vcpu_write_guest(vcpu, gpa, data, towrite); if (ret < 0) { r = X86EMUL_IO_NEEDED; goto out; } bytes -= towrite; data += towrite; addr += towrite; } out: return r; } static int emulator_write_std(struct x86_emulate_ctxt *ctxt, gva_t addr, void *val, unsigned int bytes, struct x86_exception *exception, bool system) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); u64 access = PFERR_WRITE_MASK; if (system) access |= PFERR_IMPLICIT_ACCESS; else if (static_call(kvm_x86_get_cpl)(vcpu) == 3) access |= PFERR_USER_MASK; return kvm_write_guest_virt_helper(addr, val, bytes, vcpu, access, exception); } int kvm_write_guest_virt_system(struct kvm_vcpu *vcpu, gva_t addr, void *val, unsigned int bytes, struct x86_exception *exception) { /* kvm_write_guest_virt_system can pull in tons of pages. */ vcpu->arch.l1tf_flush_l1d = true; return kvm_write_guest_virt_helper(addr, val, bytes, vcpu, PFERR_WRITE_MASK, exception); } EXPORT_SYMBOL_GPL(kvm_write_guest_virt_system); static int kvm_check_emulate_insn(struct kvm_vcpu *vcpu, int emul_type, void *insn, int insn_len) { return static_call(kvm_x86_check_emulate_instruction)(vcpu, emul_type, insn, insn_len); } int handle_ud(struct kvm_vcpu *vcpu) { static const char kvm_emulate_prefix[] = { __KVM_EMULATE_PREFIX }; int fep_flags = READ_ONCE(force_emulation_prefix); int emul_type = EMULTYPE_TRAP_UD; char sig[5]; /* ud2; .ascii "kvm" */ struct x86_exception e; int r; r = kvm_check_emulate_insn(vcpu, emul_type, NULL, 0); if (r != X86EMUL_CONTINUE) return 1; if (fep_flags && kvm_read_guest_virt(vcpu, kvm_get_linear_rip(vcpu), sig, sizeof(sig), &e) == 0 && memcmp(sig, kvm_emulate_prefix, sizeof(sig)) == 0) { if (fep_flags & KVM_FEP_CLEAR_RFLAGS_RF) kvm_set_rflags(vcpu, kvm_get_rflags(vcpu) & ~X86_EFLAGS_RF); kvm_rip_write(vcpu, kvm_rip_read(vcpu) + sizeof(sig)); emul_type = EMULTYPE_TRAP_UD_FORCED; } return kvm_emulate_instruction(vcpu, emul_type); } EXPORT_SYMBOL_GPL(handle_ud); static int vcpu_is_mmio_gpa(struct kvm_vcpu *vcpu, unsigned long gva, gpa_t gpa, bool write) { /* For APIC access vmexit */ if ((gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE) return 1; if (vcpu_match_mmio_gpa(vcpu, gpa)) { trace_vcpu_match_mmio(gva, gpa, write, true); return 1; } return 0; } static int vcpu_mmio_gva_to_gpa(struct kvm_vcpu *vcpu, unsigned long gva, gpa_t *gpa, struct x86_exception *exception, bool write) { struct kvm_mmu *mmu = vcpu->arch.walk_mmu; u64 access = ((static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0) | (write ? PFERR_WRITE_MASK : 0); /* * currently PKRU is only applied to ept enabled guest so * there is no pkey in EPT page table for L1 guest or EPT * shadow page table for L2 guest. */ if (vcpu_match_mmio_gva(vcpu, gva) && (!is_paging(vcpu) || !permission_fault(vcpu, vcpu->arch.walk_mmu, vcpu->arch.mmio_access, 0, access))) { *gpa = vcpu->arch.mmio_gfn << PAGE_SHIFT | (gva & (PAGE_SIZE - 1)); trace_vcpu_match_mmio(gva, *gpa, write, false); return 1; } *gpa = mmu->gva_to_gpa(vcpu, mmu, gva, access, exception); if (*gpa == INVALID_GPA) return -1; return vcpu_is_mmio_gpa(vcpu, gva, *gpa, write); } int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa, const void *val, int bytes) { int ret; ret = kvm_vcpu_write_guest(vcpu, gpa, val, bytes); if (ret < 0) return 0; kvm_page_track_write(vcpu, gpa, val, bytes); return 1; } struct read_write_emulator_ops { int (*read_write_prepare)(struct kvm_vcpu *vcpu, void *val, int bytes); int (*read_write_emulate)(struct kvm_vcpu *vcpu, gpa_t gpa, void *val, int bytes); int (*read_write_mmio)(struct kvm_vcpu *vcpu, gpa_t gpa, int bytes, void *val); int (*read_write_exit_mmio)(struct kvm_vcpu *vcpu, gpa_t gpa, void *val, int bytes); bool write; }; static int read_prepare(struct kvm_vcpu *vcpu, void *val, int bytes) { if (vcpu->mmio_read_completed) { trace_kvm_mmio(KVM_TRACE_MMIO_READ, bytes, vcpu->mmio_fragments[0].gpa, val); vcpu->mmio_read_completed = 0; return 1; } return 0; } static int read_emulate(struct kvm_vcpu *vcpu, gpa_t gpa, void *val, int bytes) { return !kvm_vcpu_read_guest(vcpu, gpa, val, bytes); } static int write_emulate(struct kvm_vcpu *vcpu, gpa_t gpa, void *val, int bytes) { return emulator_write_phys(vcpu, gpa, val, bytes); } static int write_mmio(struct kvm_vcpu *vcpu, gpa_t gpa, int bytes, void *val) { trace_kvm_mmio(KVM_TRACE_MMIO_WRITE, bytes, gpa, val); return vcpu_mmio_write(vcpu, gpa, bytes, val); } static int read_exit_mmio(struct kvm_vcpu *vcpu, gpa_t gpa, void *val, int bytes) { trace_kvm_mmio(KVM_TRACE_MMIO_READ_UNSATISFIED, bytes, gpa, NULL); return X86EMUL_IO_NEEDED; } static int write_exit_mmio(struct kvm_vcpu *vcpu, gpa_t gpa, void *val, int bytes) { struct kvm_mmio_fragment *frag = &vcpu->mmio_fragments[0]; memcpy(vcpu->run->mmio.data, frag->data, min(8u, frag->len)); return X86EMUL_CONTINUE; } static const struct read_write_emulator_ops read_emultor = { .read_write_prepare = read_prepare, .read_write_emulate = read_emulate, .read_write_mmio = vcpu_mmio_read, .read_write_exit_mmio = read_exit_mmio, }; static const struct read_write_emulator_ops write_emultor = { .read_write_emulate = write_emulate, .read_write_mmio = write_mmio, .read_write_exit_mmio = write_exit_mmio, .write = true, }; static int emulator_read_write_onepage(unsigned long addr, void *val, unsigned int bytes, struct x86_exception *exception, struct kvm_vcpu *vcpu, const struct read_write_emulator_ops *ops) { gpa_t gpa; int handled, ret; bool write = ops->write; struct kvm_mmio_fragment *frag; struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt; /* * If the exit was due to a NPF we may already have a GPA. * If the GPA is present, use it to avoid the GVA to GPA table walk. * Note, this cannot be used on string operations since string * operation using rep will only have the initial GPA from the NPF * occurred. */ if (ctxt->gpa_available && emulator_can_use_gpa(ctxt) && (addr & ~PAGE_MASK) == (ctxt->gpa_val & ~PAGE_MASK)) { gpa = ctxt->gpa_val; ret = vcpu_is_mmio_gpa(vcpu, addr, gpa, write); } else { ret = vcpu_mmio_gva_to_gpa(vcpu, addr, &gpa, exception, write); if (ret < 0) return X86EMUL_PROPAGATE_FAULT; } if (!ret && ops->read_write_emulate(vcpu, gpa, val, bytes)) return X86EMUL_CONTINUE; /* * Is this MMIO handled locally? */ handled = ops->read_write_mmio(vcpu, gpa, bytes, val); if (handled == bytes) return X86EMUL_CONTINUE; gpa += handled; bytes -= handled; val += handled; WARN_ON(vcpu->mmio_nr_fragments >= KVM_MAX_MMIO_FRAGMENTS); frag = &vcpu->mmio_fragments[vcpu->mmio_nr_fragments++]; frag->gpa = gpa; frag->data = val; frag->len = bytes; return X86EMUL_CONTINUE; } static int emulator_read_write(struct x86_emulate_ctxt *ctxt, unsigned long addr, void *val, unsigned int bytes, struct x86_exception *exception, const struct read_write_emulator_ops *ops) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); gpa_t gpa; int rc; if (ops->read_write_prepare && ops->read_write_prepare(vcpu, val, bytes)) return X86EMUL_CONTINUE; vcpu->mmio_nr_fragments = 0; /* Crossing a page boundary? */ if (((addr + bytes - 1) ^ addr) & PAGE_MASK) { int now; now = -addr & ~PAGE_MASK; rc = emulator_read_write_onepage(addr, val, now, exception, vcpu, ops); if (rc != X86EMUL_CONTINUE) return rc; addr += now; if (ctxt->mode != X86EMUL_MODE_PROT64) addr = (u32)addr; val += now; bytes -= now; } rc = emulator_read_write_onepage(addr, val, bytes, exception, vcpu, ops); if (rc != X86EMUL_CONTINUE) return rc; if (!vcpu->mmio_nr_fragments) return rc; gpa = vcpu->mmio_fragments[0].gpa; vcpu->mmio_needed = 1; vcpu->mmio_cur_fragment = 0; vcpu->run->mmio.len = min(8u, vcpu->mmio_fragments[0].len); vcpu->run->mmio.is_write = vcpu->mmio_is_write = ops->write; vcpu->run->exit_reason = KVM_EXIT_MMIO; vcpu->run->mmio.phys_addr = gpa; return ops->read_write_exit_mmio(vcpu, gpa, val, bytes); } static int emulator_read_emulated(struct x86_emulate_ctxt *ctxt, unsigned long addr, void *val, unsigned int bytes, struct x86_exception *exception) { return emulator_read_write(ctxt, addr, val, bytes, exception, &read_emultor); } static int emulator_write_emulated(struct x86_emulate_ctxt *ctxt, unsigned long addr, const void *val, unsigned int bytes, struct x86_exception *exception) { return emulator_read_write(ctxt, addr, (void *)val, bytes, exception, &write_emultor); } #define emulator_try_cmpxchg_user(t, ptr, old, new) \ (__try_cmpxchg_user((t __user *)(ptr), (t *)(old), *(t *)(new), efault ## t)) static int emulator_cmpxchg_emulated(struct x86_emulate_ctxt *ctxt, unsigned long addr, const void *old, const void *new, unsigned int bytes, struct x86_exception *exception) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); u64 page_line_mask; unsigned long hva; gpa_t gpa; int r; /* guests cmpxchg8b have to be emulated atomically */ if (bytes > 8 || (bytes & (bytes - 1))) goto emul_write; gpa = kvm_mmu_gva_to_gpa_write(vcpu, addr, NULL); if (gpa == INVALID_GPA || (gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE) goto emul_write; /* * Emulate the atomic as a straight write to avoid #AC if SLD is * enabled in the host and the access splits a cache line. */ if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT)) page_line_mask = ~(cache_line_size() - 1); else page_line_mask = PAGE_MASK; if (((gpa + bytes - 1) & page_line_mask) != (gpa & page_line_mask)) goto emul_write; hva = kvm_vcpu_gfn_to_hva(vcpu, gpa_to_gfn(gpa)); if (kvm_is_error_hva(hva)) goto emul_write; hva += offset_in_page(gpa); switch (bytes) { case 1: r = emulator_try_cmpxchg_user(u8, hva, old, new); break; case 2: r = emulator_try_cmpxchg_user(u16, hva, old, new); break; case 4: r = emulator_try_cmpxchg_user(u32, hva, old, new); break; case 8: r = emulator_try_cmpxchg_user(u64, hva, old, new); break; default: BUG(); } if (r < 0) return X86EMUL_UNHANDLEABLE; if (r) return X86EMUL_CMPXCHG_FAILED; kvm_page_track_write(vcpu, gpa, new, bytes); return X86EMUL_CONTINUE; emul_write: pr_warn_once("emulating exchange as write\n"); return emulator_write_emulated(ctxt, addr, new, bytes, exception); } static int emulator_pio_in_out(struct kvm_vcpu *vcpu, int size, unsigned short port, void *data, unsigned int count, bool in) { unsigned i; int r; WARN_ON_ONCE(vcpu->arch.pio.count); for (i = 0; i < count; i++) { if (in) r = kvm_io_bus_read(vcpu, KVM_PIO_BUS, port, size, data); else r = kvm_io_bus_write(vcpu, KVM_PIO_BUS, port, size, data); if (r) { if (i == 0) goto userspace_io; /* * Userspace must have unregistered the device while PIO * was running. Drop writes / read as 0. */ if (in) memset(data, 0, size * (count - i)); break; } data += size; } return 1; userspace_io: vcpu->arch.pio.port = port; vcpu->arch.pio.in = in; vcpu->arch.pio.count = count; vcpu->arch.pio.size = size; if (in) memset(vcpu->arch.pio_data, 0, size * count); else memcpy(vcpu->arch.pio_data, data, size * count); vcpu->run->exit_reason = KVM_EXIT_IO; vcpu->run->io.direction = in ? KVM_EXIT_IO_IN : KVM_EXIT_IO_OUT; vcpu->run->io.size = size; vcpu->run->io.data_offset = KVM_PIO_PAGE_OFFSET * PAGE_SIZE; vcpu->run->io.count = count; vcpu->run->io.port = port; return 0; } static int emulator_pio_in(struct kvm_vcpu *vcpu, int size, unsigned short port, void *val, unsigned int count) { int r = emulator_pio_in_out(vcpu, size, port, val, count, true); if (r) trace_kvm_pio(KVM_PIO_IN, port, size, count, val); return r; } static void complete_emulator_pio_in(struct kvm_vcpu *vcpu, void *val) { int size = vcpu->arch.pio.size; unsigned int count = vcpu->arch.pio.count; memcpy(val, vcpu->arch.pio_data, size * count); trace_kvm_pio(KVM_PIO_IN, vcpu->arch.pio.port, size, count, vcpu->arch.pio_data); vcpu->arch.pio.count = 0; } static int emulator_pio_in_emulated(struct x86_emulate_ctxt *ctxt, int size, unsigned short port, void *val, unsigned int count) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); if (vcpu->arch.pio.count) { /* * Complete a previous iteration that required userspace I/O. * Note, @count isn't guaranteed to match pio.count as userspace * can modify ECX before rerunning the vCPU. Ignore any such * shenanigans as KVM doesn't support modifying the rep count, * and the emulator ensures @count doesn't overflow the buffer. */ complete_emulator_pio_in(vcpu, val); return 1; } return emulator_pio_in(vcpu, size, port, val, count); } static int emulator_pio_out(struct kvm_vcpu *vcpu, int size, unsigned short port, const void *val, unsigned int count) { trace_kvm_pio(KVM_PIO_OUT, port, size, count, val); return emulator_pio_in_out(vcpu, size, port, (void *)val, count, false); } static int emulator_pio_out_emulated(struct x86_emulate_ctxt *ctxt, int size, unsigned short port, const void *val, unsigned int count) { return emulator_pio_out(emul_to_vcpu(ctxt), size, port, val, count); } static unsigned long get_segment_base(struct kvm_vcpu *vcpu, int seg) { return static_call(kvm_x86_get_segment_base)(vcpu, seg); } static void emulator_invlpg(struct x86_emulate_ctxt *ctxt, ulong address) { kvm_mmu_invlpg(emul_to_vcpu(ctxt), address); } static int kvm_emulate_wbinvd_noskip(struct kvm_vcpu *vcpu) { if (!need_emulate_wbinvd(vcpu)) return X86EMUL_CONTINUE; if (static_call(kvm_x86_has_wbinvd_exit)()) { int cpu = get_cpu(); cpumask_set_cpu(cpu, vcpu->arch.wbinvd_dirty_mask); on_each_cpu_mask(vcpu->arch.wbinvd_dirty_mask, wbinvd_ipi, NULL, 1); put_cpu(); cpumask_clear(vcpu->arch.wbinvd_dirty_mask); } else wbinvd(); return X86EMUL_CONTINUE; } int kvm_emulate_wbinvd(struct kvm_vcpu *vcpu) { kvm_emulate_wbinvd_noskip(vcpu); return kvm_skip_emulated_instruction(vcpu); } EXPORT_SYMBOL_GPL(kvm_emulate_wbinvd); static void emulator_wbinvd(struct x86_emulate_ctxt *ctxt) { kvm_emulate_wbinvd_noskip(emul_to_vcpu(ctxt)); } static unsigned long emulator_get_dr(struct x86_emulate_ctxt *ctxt, int dr) { return kvm_get_dr(emul_to_vcpu(ctxt), dr); } static int emulator_set_dr(struct x86_emulate_ctxt *ctxt, int dr, unsigned long value) { return kvm_set_dr(emul_to_vcpu(ctxt), dr, value); } static u64 mk_cr_64(u64 curr_cr, u32 new_val) { return (curr_cr & ~((1ULL << 32) - 1)) | new_val; } static unsigned long emulator_get_cr(struct x86_emulate_ctxt *ctxt, int cr) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); unsigned long value; switch (cr) { case 0: value = kvm_read_cr0(vcpu); break; case 2: value = vcpu->arch.cr2; break; case 3: value = kvm_read_cr3(vcpu); break; case 4: value = kvm_read_cr4(vcpu); break; case 8: value = kvm_get_cr8(vcpu); break; default: kvm_err("%s: unexpected cr %u\n", __func__, cr); return 0; } return value; } static int emulator_set_cr(struct x86_emulate_ctxt *ctxt, int cr, ulong val) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); int res = 0; switch (cr) { case 0: res = kvm_set_cr0(vcpu, mk_cr_64(kvm_read_cr0(vcpu), val)); break; case 2: vcpu->arch.cr2 = val; break; case 3: res = kvm_set_cr3(vcpu, val); break; case 4: res = kvm_set_cr4(vcpu, mk_cr_64(kvm_read_cr4(vcpu), val)); break; case 8: res = kvm_set_cr8(vcpu, val); break; default: kvm_err("%s: unexpected cr %u\n", __func__, cr); res = -1; } return res; } static int emulator_get_cpl(struct x86_emulate_ctxt *ctxt) { return static_call(kvm_x86_get_cpl)(emul_to_vcpu(ctxt)); } static void emulator_get_gdt(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt) { static_call(kvm_x86_get_gdt)(emul_to_vcpu(ctxt), dt); } static void emulator_get_idt(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt) { static_call(kvm_x86_get_idt)(emul_to_vcpu(ctxt), dt); } static void emulator_set_gdt(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt) { static_call(kvm_x86_set_gdt)(emul_to_vcpu(ctxt), dt); } static void emulator_set_idt(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt) { static_call(kvm_x86_set_idt)(emul_to_vcpu(ctxt), dt); } static unsigned long emulator_get_cached_segment_base( struct x86_emulate_ctxt *ctxt, int seg) { return get_segment_base(emul_to_vcpu(ctxt), seg); } static bool emulator_get_segment(struct x86_emulate_ctxt *ctxt, u16 *selector, struct desc_struct *desc, u32 *base3, int seg) { struct kvm_segment var; kvm_get_segment(emul_to_vcpu(ctxt), &var, seg); *selector = var.selector; if (var.unusable) { memset(desc, 0, sizeof(*desc)); if (base3) *base3 = 0; return false; } if (var.g) var.limit >>= 12; set_desc_limit(desc, var.limit); set_desc_base(desc, (unsigned long)var.base); #ifdef CONFIG_X86_64 if (base3) *base3 = var.base >> 32; #endif desc->type = var.type; desc->s = var.s; desc->dpl = var.dpl; desc->p = var.present; desc->avl = var.avl; desc->l = var.l; desc->d = var.db; desc->g = var.g; return true; } static void emulator_set_segment(struct x86_emulate_ctxt *ctxt, u16 selector, struct desc_struct *desc, u32 base3, int seg) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); struct kvm_segment var; var.selector = selector; var.base = get_desc_base(desc); #ifdef CONFIG_X86_64 var.base |= ((u64)base3) << 32; #endif var.limit = get_desc_limit(desc); if (desc->g) var.limit = (var.limit << 12) | 0xfff; var.type = desc->type; var.dpl = desc->dpl; var.db = desc->d; var.s = desc->s; var.l = desc->l; var.g = desc->g; var.avl = desc->avl; var.present = desc->p; var.unusable = !var.present; var.padding = 0; kvm_set_segment(vcpu, &var, seg); return; } static int emulator_get_msr_with_filter(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 *pdata) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); int r; r = kvm_get_msr_with_filter(vcpu, msr_index, pdata); if (r < 0) return X86EMUL_UNHANDLEABLE; if (r) { if (kvm_msr_user_space(vcpu, msr_index, KVM_EXIT_X86_RDMSR, 0, complete_emulated_rdmsr, r)) return X86EMUL_IO_NEEDED; trace_kvm_msr_read_ex(msr_index); return X86EMUL_PROPAGATE_FAULT; } trace_kvm_msr_read(msr_index, *pdata); return X86EMUL_CONTINUE; } static int emulator_set_msr_with_filter(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 data) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); int r; r = kvm_set_msr_with_filter(vcpu, msr_index, data); if (r < 0) return X86EMUL_UNHANDLEABLE; if (r) { if (kvm_msr_user_space(vcpu, msr_index, KVM_EXIT_X86_WRMSR, data, complete_emulated_msr_access, r)) return X86EMUL_IO_NEEDED; trace_kvm_msr_write_ex(msr_index, data); return X86EMUL_PROPAGATE_FAULT; } trace_kvm_msr_write(msr_index, data); return X86EMUL_CONTINUE; } static int emulator_get_msr(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 *pdata) { return kvm_get_msr(emul_to_vcpu(ctxt), msr_index, pdata); } static int emulator_check_pmc(struct x86_emulate_ctxt *ctxt, u32 pmc) { if (kvm_pmu_is_valid_rdpmc_ecx(emul_to_vcpu(ctxt), pmc)) return 0; return -EINVAL; } static int emulator_read_pmc(struct x86_emulate_ctxt *ctxt, u32 pmc, u64 *pdata) { return kvm_pmu_rdpmc(emul_to_vcpu(ctxt), pmc, pdata); } static void emulator_halt(struct x86_emulate_ctxt *ctxt) { emul_to_vcpu(ctxt)->arch.halt_request = 1; } static int emulator_intercept(struct x86_emulate_ctxt *ctxt, struct x86_instruction_info *info, enum x86_intercept_stage stage) { return static_call(kvm_x86_check_intercept)(emul_to_vcpu(ctxt), info, stage, &ctxt->exception); } static bool emulator_get_cpuid(struct x86_emulate_ctxt *ctxt, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx, bool exact_only) { return kvm_cpuid(emul_to_vcpu(ctxt), eax, ebx, ecx, edx, exact_only); } static bool emulator_guest_has_movbe(struct x86_emulate_ctxt *ctxt) { return guest_cpuid_has(emul_to_vcpu(ctxt), X86_FEATURE_MOVBE); } static bool emulator_guest_has_fxsr(struct x86_emulate_ctxt *ctxt) { return guest_cpuid_has(emul_to_vcpu(ctxt), X86_FEATURE_FXSR); } static bool emulator_guest_has_rdpid(struct x86_emulate_ctxt *ctxt) { return guest_cpuid_has(emul_to_vcpu(ctxt), X86_FEATURE_RDPID); } static ulong emulator_read_gpr(struct x86_emulate_ctxt *ctxt, unsigned reg) { return kvm_register_read_raw(emul_to_vcpu(ctxt), reg); } static void emulator_write_gpr(struct x86_emulate_ctxt *ctxt, unsigned reg, ulong val) { kvm_register_write_raw(emul_to_vcpu(ctxt), reg, val); } static void emulator_set_nmi_mask(struct x86_emulate_ctxt *ctxt, bool masked) { static_call(kvm_x86_set_nmi_mask)(emul_to_vcpu(ctxt), masked); } static bool emulator_is_smm(struct x86_emulate_ctxt *ctxt) { return is_smm(emul_to_vcpu(ctxt)); } static bool emulator_is_guest_mode(struct x86_emulate_ctxt *ctxt) { return is_guest_mode(emul_to_vcpu(ctxt)); } #ifndef CONFIG_KVM_SMM static int emulator_leave_smm(struct x86_emulate_ctxt *ctxt) { WARN_ON_ONCE(1); return X86EMUL_UNHANDLEABLE; } #endif static void emulator_triple_fault(struct x86_emulate_ctxt *ctxt) { kvm_make_request(KVM_REQ_TRIPLE_FAULT, emul_to_vcpu(ctxt)); } static int emulator_set_xcr(struct x86_emulate_ctxt *ctxt, u32 index, u64 xcr) { return __kvm_set_xcr(emul_to_vcpu(ctxt), index, xcr); } static void emulator_vm_bugged(struct x86_emulate_ctxt *ctxt) { struct kvm *kvm = emul_to_vcpu(ctxt)->kvm; if (!kvm->vm_bugged) kvm_vm_bugged(kvm); } static gva_t emulator_get_untagged_addr(struct x86_emulate_ctxt *ctxt, gva_t addr, unsigned int flags) { if (!kvm_x86_ops.get_untagged_addr) return addr; return static_call(kvm_x86_get_untagged_addr)(emul_to_vcpu(ctxt), addr, flags); } static const struct x86_emulate_ops emulate_ops = { .vm_bugged = emulator_vm_bugged, .read_gpr = emulator_read_gpr, .write_gpr = emulator_write_gpr, .read_std = emulator_read_std, .write_std = emulator_write_std, .fetch = kvm_fetch_guest_virt, .read_emulated = emulator_read_emulated, .write_emulated = emulator_write_emulated, .cmpxchg_emulated = emulator_cmpxchg_emulated, .invlpg = emulator_invlpg, .pio_in_emulated = emulator_pio_in_emulated, .pio_out_emulated = emulator_pio_out_emulated, .get_segment = emulator_get_segment, .set_segment = emulator_set_segment, .get_cached_segment_base = emulator_get_cached_segment_base, .get_gdt = emulator_get_gdt, .get_idt = emulator_get_idt, .set_gdt = emulator_set_gdt, .set_idt = emulator_set_idt, .get_cr = emulator_get_cr, .set_cr = emulator_set_cr, .cpl = emulator_get_cpl, .get_dr = emulator_get_dr, .set_dr = emulator_set_dr, .set_msr_with_filter = emulator_set_msr_with_filter, .get_msr_with_filter = emulator_get_msr_with_filter, .get_msr = emulator_get_msr, .check_pmc = emulator_check_pmc, .read_pmc = emulator_read_pmc, .halt = emulator_halt, .wbinvd = emulator_wbinvd, .fix_hypercall = emulator_fix_hypercall, .intercept = emulator_intercept, .get_cpuid = emulator_get_cpuid, .guest_has_movbe = emulator_guest_has_movbe, .guest_has_fxsr = emulator_guest_has_fxsr, .guest_has_rdpid = emulator_guest_has_rdpid, .set_nmi_mask = emulator_set_nmi_mask, .is_smm = emulator_is_smm, .is_guest_mode = emulator_is_guest_mode, .leave_smm = emulator_leave_smm, .triple_fault = emulator_triple_fault, .set_xcr = emulator_set_xcr, .get_untagged_addr = emulator_get_untagged_addr, }; static void toggle_interruptibility(struct kvm_vcpu *vcpu, u32 mask) { u32 int_shadow = static_call(kvm_x86_get_interrupt_shadow)(vcpu); /* * an sti; sti; sequence only disable interrupts for the first * instruction. So, if the last instruction, be it emulated or * not, left the system with the INT_STI flag enabled, it * means that the last instruction is an sti. We should not * leave the flag on in this case. The same goes for mov ss */ if (int_shadow & mask) mask = 0; if (unlikely(int_shadow || mask)) { static_call(kvm_x86_set_interrupt_shadow)(vcpu, mask); if (!mask) kvm_make_request(KVM_REQ_EVENT, vcpu); } } static void inject_emulated_exception(struct kvm_vcpu *vcpu) { struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt; if (ctxt->exception.vector == PF_VECTOR) kvm_inject_emulated_page_fault(vcpu, &ctxt->exception); else if (ctxt->exception.error_code_valid) kvm_queue_exception_e(vcpu, ctxt->exception.vector, ctxt->exception.error_code); else kvm_queue_exception(vcpu, ctxt->exception.vector); } static struct x86_emulate_ctxt *alloc_emulate_ctxt(struct kvm_vcpu *vcpu) { struct x86_emulate_ctxt *ctxt; ctxt = kmem_cache_zalloc(x86_emulator_cache, GFP_KERNEL_ACCOUNT); if (!ctxt) { pr_err("failed to allocate vcpu's emulator\n"); return NULL; } ctxt->vcpu = vcpu; ctxt->ops = &emulate_ops; vcpu->arch.emulate_ctxt = ctxt; return ctxt; } static void init_emulate_ctxt(struct kvm_vcpu *vcpu) { struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt; int cs_db, cs_l; static_call(kvm_x86_get_cs_db_l_bits)(vcpu, &cs_db, &cs_l); ctxt->gpa_available = false; ctxt->eflags = kvm_get_rflags(vcpu); ctxt->tf = (ctxt->eflags & X86_EFLAGS_TF) != 0; ctxt->eip = kvm_rip_read(vcpu); ctxt->mode = (!is_protmode(vcpu)) ? X86EMUL_MODE_REAL : (ctxt->eflags & X86_EFLAGS_VM) ? X86EMUL_MODE_VM86 : (cs_l && is_long_mode(vcpu)) ? X86EMUL_MODE_PROT64 : cs_db ? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16; ctxt->interruptibility = 0; ctxt->have_exception = false; ctxt->exception.vector = -1; ctxt->perm_ok = false; init_decode_cache(ctxt); vcpu->arch.emulate_regs_need_sync_from_vcpu = false; } void kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq, int inc_eip) { struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt; int ret; init_emulate_ctxt(vcpu); ctxt->op_bytes = 2; ctxt->ad_bytes = 2; ctxt->_eip = ctxt->eip + inc_eip; ret = emulate_int_real(ctxt, irq); if (ret != X86EMUL_CONTINUE) { kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu); } else { ctxt->eip = ctxt->_eip; kvm_rip_write(vcpu, ctxt->eip); kvm_set_rflags(vcpu, ctxt->eflags); } } EXPORT_SYMBOL_GPL(kvm_inject_realmode_interrupt); static void prepare_emulation_failure_exit(struct kvm_vcpu *vcpu, u64 *data, u8 ndata, u8 *insn_bytes, u8 insn_size) { struct kvm_run *run = vcpu->run; u64 info[5]; u8 info_start; /* * Zero the whole array used to retrieve the exit info, as casting to * u32 for select entries will leave some chunks uninitialized. */ memset(&info, 0, sizeof(info)); static_call(kvm_x86_get_exit_info)(vcpu, (u32 *)&info[0], &info[1], &info[2], (u32 *)&info[3], (u32 *)&info[4]); run->exit_reason = KVM_EXIT_INTERNAL_ERROR; run->emulation_failure.suberror = KVM_INTERNAL_ERROR_EMULATION; /* * There's currently space for 13 entries, but 5 are used for the exit * reason and info. Restrict to 4 to reduce the maintenance burden * when expanding kvm_run.emulation_failure in the future. */ if (WARN_ON_ONCE(ndata > 4)) ndata = 4; /* Always include the flags as a 'data' entry. */ info_start = 1; run->emulation_failure.flags = 0; if (insn_size) { BUILD_BUG_ON((sizeof(run->emulation_failure.insn_size) + sizeof(run->emulation_failure.insn_bytes) != 16)); info_start += 2; run->emulation_failure.flags |= KVM_INTERNAL_ERROR_EMULATION_FLAG_INSTRUCTION_BYTES; run->emulation_failure.insn_size = insn_size; memset(run->emulation_failure.insn_bytes, 0x90, sizeof(run->emulation_failure.insn_bytes)); memcpy(run->emulation_failure.insn_bytes, insn_bytes, insn_size); } memcpy(&run->internal.data[info_start], info, sizeof(info)); memcpy(&run->internal.data[info_start + ARRAY_SIZE(info)], data, ndata * sizeof(data[0])); run->emulation_failure.ndata = info_start + ARRAY_SIZE(info) + ndata; } static void prepare_emulation_ctxt_failure_exit(struct kvm_vcpu *vcpu) { struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt; prepare_emulation_failure_exit(vcpu, NULL, 0, ctxt->fetch.data, ctxt->fetch.end - ctxt->fetch.data); } void __kvm_prepare_emulation_failure_exit(struct kvm_vcpu *vcpu, u64 *data, u8 ndata) { prepare_emulation_failure_exit(vcpu, data, ndata, NULL, 0); } EXPORT_SYMBOL_GPL(__kvm_prepare_emulation_failure_exit); void kvm_prepare_emulation_failure_exit(struct kvm_vcpu *vcpu) { __kvm_prepare_emulation_failure_exit(vcpu, NULL, 0); } EXPORT_SYMBOL_GPL(kvm_prepare_emulation_failure_exit); static int handle_emulation_failure(struct kvm_vcpu *vcpu, int emulation_type) { struct kvm *kvm = vcpu->kvm; ++vcpu->stat.insn_emulation_fail; trace_kvm_emulate_insn_failed(vcpu); if (emulation_type & EMULTYPE_VMWARE_GP) { kvm_queue_exception_e(vcpu, GP_VECTOR, 0); return 1; } if (kvm->arch.exit_on_emulation_error || (emulation_type & EMULTYPE_SKIP)) { prepare_emulation_ctxt_failure_exit(vcpu); return 0; } kvm_queue_exception(vcpu, UD_VECTOR); if (!is_guest_mode(vcpu) && static_call(kvm_x86_get_cpl)(vcpu) == 0) { prepare_emulation_ctxt_failure_exit(vcpu); return 0; } return 1; } static bool reexecute_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, int emulation_type) { gpa_t gpa = cr2_or_gpa; kvm_pfn_t pfn; if (!(emulation_type & EMULTYPE_ALLOW_RETRY_PF)) return false; if (WARN_ON_ONCE(is_guest_mode(vcpu)) || WARN_ON_ONCE(!(emulation_type & EMULTYPE_PF))) return false; if (!vcpu->arch.mmu->root_role.direct) { /* * Write permission should be allowed since only * write access need to be emulated. */ gpa = kvm_mmu_gva_to_gpa_write(vcpu, cr2_or_gpa, NULL); /* * If the mapping is invalid in guest, let cpu retry * it to generate fault. */ if (gpa == INVALID_GPA) return true; } /* * Do not retry the unhandleable instruction if it faults on the * readonly host memory, otherwise it will goto a infinite loop: * retry instruction -> write #PF -> emulation fail -> retry * instruction -> ... */ pfn = gfn_to_pfn(vcpu->kvm, gpa_to_gfn(gpa)); /* * If the instruction failed on the error pfn, it can not be fixed, * report the error to userspace. */ if (is_error_noslot_pfn(pfn)) return false; kvm_release_pfn_clean(pfn); /* The instructions are well-emulated on direct mmu. */ if (vcpu->arch.mmu->root_role.direct) { unsigned int indirect_shadow_pages; write_lock(&vcpu->kvm->mmu_lock); indirect_shadow_pages = vcpu->kvm->arch.indirect_shadow_pages; write_unlock(&vcpu->kvm->mmu_lock); if (indirect_shadow_pages) kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(gpa)); return true; } /* * if emulation was due to access to shadowed page table * and it failed try to unshadow page and re-enter the * guest to let CPU execute the instruction. */ kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(gpa)); /* * If the access faults on its page table, it can not * be fixed by unprotecting shadow page and it should * be reported to userspace. */ return !(emulation_type & EMULTYPE_WRITE_PF_TO_SP); } static bool retry_instruction(struct x86_emulate_ctxt *ctxt, gpa_t cr2_or_gpa, int emulation_type) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); unsigned long last_retry_eip, last_retry_addr, gpa = cr2_or_gpa; last_retry_eip = vcpu->arch.last_retry_eip; last_retry_addr = vcpu->arch.last_retry_addr; /* * If the emulation is caused by #PF and it is non-page_table * writing instruction, it means the VM-EXIT is caused by shadow * page protected, we can zap the shadow page and retry this * instruction directly. * * Note: if the guest uses a non-page-table modifying instruction * on the PDE that points to the instruction, then we will unmap * the instruction and go to an infinite loop. So, we cache the * last retried eip and the last fault address, if we meet the eip * and the address again, we can break out of the potential infinite * loop. */ vcpu->arch.last_retry_eip = vcpu->arch.last_retry_addr = 0; if (!(emulation_type & EMULTYPE_ALLOW_RETRY_PF)) return false; if (WARN_ON_ONCE(is_guest_mode(vcpu)) || WARN_ON_ONCE(!(emulation_type & EMULTYPE_PF))) return false; if (x86_page_table_writing_insn(ctxt)) return false; if (ctxt->eip == last_retry_eip && last_retry_addr == cr2_or_gpa) return false; vcpu->arch.last_retry_eip = ctxt->eip; vcpu->arch.last_retry_addr = cr2_or_gpa; if (!vcpu->arch.mmu->root_role.direct) gpa = kvm_mmu_gva_to_gpa_write(vcpu, cr2_or_gpa, NULL); kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(gpa)); return true; } static int complete_emulated_mmio(struct kvm_vcpu *vcpu); static int complete_emulated_pio(struct kvm_vcpu *vcpu); static int kvm_vcpu_check_hw_bp(unsigned long addr, u32 type, u32 dr7, unsigned long *db) { u32 dr6 = 0; int i; u32 enable, rwlen; enable = dr7; rwlen = dr7 >> 16; for (i = 0; i < 4; i++, enable >>= 2, rwlen >>= 4) if ((enable & 3) && (rwlen & 15) == type && db[i] == addr) dr6 |= (1 << i); return dr6; } static int kvm_vcpu_do_singlestep(struct kvm_vcpu *vcpu) { struct kvm_run *kvm_run = vcpu->run; if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) { kvm_run->debug.arch.dr6 = DR6_BS | DR6_ACTIVE_LOW; kvm_run->debug.arch.pc = kvm_get_linear_rip(vcpu); kvm_run->debug.arch.exception = DB_VECTOR; kvm_run->exit_reason = KVM_EXIT_DEBUG; return 0; } kvm_queue_exception_p(vcpu, DB_VECTOR, DR6_BS); return 1; } int kvm_skip_emulated_instruction(struct kvm_vcpu *vcpu) { unsigned long rflags = static_call(kvm_x86_get_rflags)(vcpu); int r; r = static_call(kvm_x86_skip_emulated_instruction)(vcpu); if (unlikely(!r)) return 0; kvm_pmu_trigger_event(vcpu, PERF_COUNT_HW_INSTRUCTIONS); /* * rflags is the old, "raw" value of the flags. The new value has * not been saved yet. * * This is correct even for TF set by the guest, because "the * processor will not generate this exception after the instruction * that sets the TF flag". */ if (unlikely(rflags & X86_EFLAGS_TF)) r = kvm_vcpu_do_singlestep(vcpu); return r; } EXPORT_SYMBOL_GPL(kvm_skip_emulated_instruction); static bool kvm_is_code_breakpoint_inhibited(struct kvm_vcpu *vcpu) { u32 shadow; if (kvm_get_rflags(vcpu) & X86_EFLAGS_RF) return true; /* * Intel CPUs inhibit code #DBs when MOV/POP SS blocking is active, * but AMD CPUs do not. MOV/POP SS blocking is rare, check that first * to avoid the relatively expensive CPUID lookup. */ shadow = static_call(kvm_x86_get_interrupt_shadow)(vcpu); return (shadow & KVM_X86_SHADOW_INT_MOV_SS) && guest_cpuid_is_intel(vcpu); } static bool kvm_vcpu_check_code_breakpoint(struct kvm_vcpu *vcpu, int emulation_type, int *r) { WARN_ON_ONCE(emulation_type & EMULTYPE_NO_DECODE); /* * Do not check for code breakpoints if hardware has already done the * checks, as inferred from the emulation type. On NO_DECODE and SKIP, * the instruction has passed all exception checks, and all intercepted * exceptions that trigger emulation have lower priority than code * breakpoints, i.e. the fact that the intercepted exception occurred * means any code breakpoints have already been serviced. * * Note, KVM needs to check for code #DBs on EMULTYPE_TRAP_UD_FORCED as * hardware has checked the RIP of the magic prefix, but not the RIP of * the instruction being emulated. The intent of forced emulation is * to behave as if KVM intercepted the instruction without an exception * and without a prefix. */ if (emulation_type & (EMULTYPE_NO_DECODE | EMULTYPE_SKIP | EMULTYPE_TRAP_UD | EMULTYPE_VMWARE_GP | EMULTYPE_PF)) return false; if (unlikely(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP) && (vcpu->arch.guest_debug_dr7 & DR7_BP_EN_MASK)) { struct kvm_run *kvm_run = vcpu->run; unsigned long eip = kvm_get_linear_rip(vcpu); u32 dr6 = kvm_vcpu_check_hw_bp(eip, 0, vcpu->arch.guest_debug_dr7, vcpu->arch.eff_db); if (dr6 != 0) { kvm_run->debug.arch.dr6 = dr6 | DR6_ACTIVE_LOW; kvm_run->debug.arch.pc = eip; kvm_run->debug.arch.exception = DB_VECTOR; kvm_run->exit_reason = KVM_EXIT_DEBUG; *r = 0; return true; } } if (unlikely(vcpu->arch.dr7 & DR7_BP_EN_MASK) && !kvm_is_code_breakpoint_inhibited(vcpu)) { unsigned long eip = kvm_get_linear_rip(vcpu); u32 dr6 = kvm_vcpu_check_hw_bp(eip, 0, vcpu->arch.dr7, vcpu->arch.db); if (dr6 != 0) { kvm_queue_exception_p(vcpu, DB_VECTOR, dr6); *r = 1; return true; } } return false; } static bool is_vmware_backdoor_opcode(struct x86_emulate_ctxt *ctxt) { switch (ctxt->opcode_len) { case 1: switch (ctxt->b) { case 0xe4: /* IN */ case 0xe5: case 0xec: case 0xed: case 0xe6: /* OUT */ case 0xe7: case 0xee: case 0xef: case 0x6c: /* INS */ case 0x6d: case 0x6e: /* OUTS */ case 0x6f: return true; } break; case 2: switch (ctxt->b) { case 0x33: /* RDPMC */ return true; } break; } return false; } /* * Decode an instruction for emulation. The caller is responsible for handling * code breakpoints. Note, manually detecting code breakpoints is unnecessary * (and wrong) when emulating on an intercepted fault-like exception[*], as * code breakpoints have higher priority and thus have already been done by * hardware. * * [*] Except #MC, which is higher priority, but KVM should never emulate in * response to a machine check. */ int x86_decode_emulated_instruction(struct kvm_vcpu *vcpu, int emulation_type, void *insn, int insn_len) { struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt; int r; init_emulate_ctxt(vcpu); r = x86_decode_insn(ctxt, insn, insn_len, emulation_type); trace_kvm_emulate_insn_start(vcpu); ++vcpu->stat.insn_emulation; return r; } EXPORT_SYMBOL_GPL(x86_decode_emulated_instruction); int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, int emulation_type, void *insn, int insn_len) { int r; struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt; bool writeback = true; r = kvm_check_emulate_insn(vcpu, emulation_type, insn, insn_len); if (r != X86EMUL_CONTINUE) { if (r == X86EMUL_RETRY_INSTR || r == X86EMUL_PROPAGATE_FAULT) return 1; WARN_ON_ONCE(r != X86EMUL_UNHANDLEABLE); return handle_emulation_failure(vcpu, emulation_type); } vcpu->arch.l1tf_flush_l1d = true; if (!(emulation_type & EMULTYPE_NO_DECODE)) { kvm_clear_exception_queue(vcpu); /* * Return immediately if RIP hits a code breakpoint, such #DBs * are fault-like and are higher priority than any faults on * the code fetch itself. */ if (kvm_vcpu_check_code_breakpoint(vcpu, emulation_type, &r)) return r; r = x86_decode_emulated_instruction(vcpu, emulation_type, insn, insn_len); if (r != EMULATION_OK) { if ((emulation_type & EMULTYPE_TRAP_UD) || (emulation_type & EMULTYPE_TRAP_UD_FORCED)) { kvm_queue_exception(vcpu, UD_VECTOR); return 1; } if (reexecute_instruction(vcpu, cr2_or_gpa, emulation_type)) return 1; if (ctxt->have_exception && !(emulation_type & EMULTYPE_SKIP)) { /* * #UD should result in just EMULATION_FAILED, and trap-like * exception should not be encountered during decode. */ WARN_ON_ONCE(ctxt->exception.vector == UD_VECTOR || exception_type(ctxt->exception.vector) == EXCPT_TRAP); inject_emulated_exception(vcpu); return 1; } return handle_emulation_failure(vcpu, emulation_type); } } if ((emulation_type & EMULTYPE_VMWARE_GP) && !is_vmware_backdoor_opcode(ctxt)) { kvm_queue_exception_e(vcpu, GP_VECTOR, 0); return 1; } /* * EMULTYPE_SKIP without EMULTYPE_COMPLETE_USER_EXIT is intended for * use *only* by vendor callbacks for kvm_skip_emulated_instruction(). * The caller is responsible for updating interruptibility state and * injecting single-step #DBs. */ if (emulation_type & EMULTYPE_SKIP) { if (ctxt->mode != X86EMUL_MODE_PROT64) ctxt->eip = (u32)ctxt->_eip; else ctxt->eip = ctxt->_eip; if (emulation_type & EMULTYPE_COMPLETE_USER_EXIT) { r = 1; goto writeback; } kvm_rip_write(vcpu, ctxt->eip); if (ctxt->eflags & X86_EFLAGS_RF) kvm_set_rflags(vcpu, ctxt->eflags & ~X86_EFLAGS_RF); return 1; } if (retry_instruction(ctxt, cr2_or_gpa, emulation_type)) return 1; /* this is needed for vmware backdoor interface to work since it changes registers values during IO operation */ if (vcpu->arch.emulate_regs_need_sync_from_vcpu) { vcpu->arch.emulate_regs_need_sync_from_vcpu = false; emulator_invalidate_register_cache(ctxt); } restart: if (emulation_type & EMULTYPE_PF) { /* Save the faulting GPA (cr2) in the address field */ ctxt->exception.address = cr2_or_gpa; /* With shadow page tables, cr2 contains a GVA or nGPA. */ if (vcpu->arch.mmu->root_role.direct) { ctxt->gpa_available = true; ctxt->gpa_val = cr2_or_gpa; } } else { /* Sanitize the address out of an abundance of paranoia. */ ctxt->exception.address = 0; } r = x86_emulate_insn(ctxt); if (r == EMULATION_INTERCEPTED) return 1; if (r == EMULATION_FAILED) { if (reexecute_instruction(vcpu, cr2_or_gpa, emulation_type)) return 1; return handle_emulation_failure(vcpu, emulation_type); } if (ctxt->have_exception) { WARN_ON_ONCE(vcpu->mmio_needed && !vcpu->mmio_is_write); vcpu->mmio_needed = false; r = 1; inject_emulated_exception(vcpu); } else if (vcpu->arch.pio.count) { if (!vcpu->arch.pio.in) { /* FIXME: return into emulator if single-stepping. */ vcpu->arch.pio.count = 0; } else { writeback = false; vcpu->arch.complete_userspace_io = complete_emulated_pio; } r = 0; } else if (vcpu->mmio_needed) { ++vcpu->stat.mmio_exits; if (!vcpu->mmio_is_write) writeback = false; r = 0; vcpu->arch.complete_userspace_io = complete_emulated_mmio; } else if (vcpu->arch.complete_userspace_io) { writeback = false; r = 0; } else if (r == EMULATION_RESTART) goto restart; else r = 1; writeback: if (writeback) { unsigned long rflags = static_call(kvm_x86_get_rflags)(vcpu); toggle_interruptibility(vcpu, ctxt->interruptibility); vcpu->arch.emulate_regs_need_sync_to_vcpu = false; /* * Note, EXCPT_DB is assumed to be fault-like as the emulator * only supports code breakpoints and general detect #DB, both * of which are fault-like. */ if (!ctxt->have_exception || exception_type(ctxt->exception.vector) == EXCPT_TRAP) { kvm_pmu_trigger_event(vcpu, PERF_COUNT_HW_INSTRUCTIONS); if (ctxt->is_branch) kvm_pmu_trigger_event(vcpu, PERF_COUNT_HW_BRANCH_INSTRUCTIONS); kvm_rip_write(vcpu, ctxt->eip); if (r && (ctxt->tf || (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP))) r = kvm_vcpu_do_singlestep(vcpu); static_call_cond(kvm_x86_update_emulated_instruction)(vcpu); __kvm_set_rflags(vcpu, ctxt->eflags); } /* * For STI, interrupts are shadowed; so KVM_REQ_EVENT will * do nothing, and it will be requested again as soon as * the shadow expires. But we still need to check here, * because POPF has no interrupt shadow. */ if (unlikely((ctxt->eflags & ~rflags) & X86_EFLAGS_IF)) kvm_make_request(KVM_REQ_EVENT, vcpu); } else vcpu->arch.emulate_regs_need_sync_to_vcpu = true; return r; } int kvm_emulate_instruction(struct kvm_vcpu *vcpu, int emulation_type) { return x86_emulate_instruction(vcpu, 0, emulation_type, NULL, 0); } EXPORT_SYMBOL_GPL(kvm_emulate_instruction); int kvm_emulate_instruction_from_buffer(struct kvm_vcpu *vcpu, void *insn, int insn_len) { return x86_emulate_instruction(vcpu, 0, 0, insn, insn_len); } EXPORT_SYMBOL_GPL(kvm_emulate_instruction_from_buffer); static int complete_fast_pio_out_port_0x7e(struct kvm_vcpu *vcpu) { vcpu->arch.pio.count = 0; return 1; } static int complete_fast_pio_out(struct kvm_vcpu *vcpu) { vcpu->arch.pio.count = 0; if (unlikely(!kvm_is_linear_rip(vcpu, vcpu->arch.pio.linear_rip))) return 1; return kvm_skip_emulated_instruction(vcpu); } static int kvm_fast_pio_out(struct kvm_vcpu *vcpu, int size, unsigned short port) { unsigned long val = kvm_rax_read(vcpu); int ret = emulator_pio_out(vcpu, size, port, &val, 1); if (ret) return ret; /* * Workaround userspace that relies on old KVM behavior of %rip being * incremented prior to exiting to userspace to handle "OUT 0x7e". */ if (port == 0x7e && kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_OUT_7E_INC_RIP)) { vcpu->arch.complete_userspace_io = complete_fast_pio_out_port_0x7e; kvm_skip_emulated_instruction(vcpu); } else { vcpu->arch.pio.linear_rip = kvm_get_linear_rip(vcpu); vcpu->arch.complete_userspace_io = complete_fast_pio_out; } return 0; } static int complete_fast_pio_in(struct kvm_vcpu *vcpu) { unsigned long val; /* We should only ever be called with arch.pio.count equal to 1 */ BUG_ON(vcpu->arch.pio.count != 1); if (unlikely(!kvm_is_linear_rip(vcpu, vcpu->arch.pio.linear_rip))) { vcpu->arch.pio.count = 0; return 1; } /* For size less than 4 we merge, else we zero extend */ val = (vcpu->arch.pio.size < 4) ? kvm_rax_read(vcpu) : 0; complete_emulator_pio_in(vcpu, &val); kvm_rax_write(vcpu, val); return kvm_skip_emulated_instruction(vcpu); } static int kvm_fast_pio_in(struct kvm_vcpu *vcpu, int size, unsigned short port) { unsigned long val; int ret; /* For size less than 4 we merge, else we zero extend */ val = (size < 4) ? kvm_rax_read(vcpu) : 0; ret = emulator_pio_in(vcpu, size, port, &val, 1); if (ret) { kvm_rax_write(vcpu, val); return ret; } vcpu->arch.pio.linear_rip = kvm_get_linear_rip(vcpu); vcpu->arch.complete_userspace_io = complete_fast_pio_in; return 0; } int kvm_fast_pio(struct kvm_vcpu *vcpu, int size, unsigned short port, int in) { int ret; if (in) ret = kvm_fast_pio_in(vcpu, size, port); else ret = kvm_fast_pio_out(vcpu, size, port); return ret && kvm_skip_emulated_instruction(vcpu); } EXPORT_SYMBOL_GPL(kvm_fast_pio); static int kvmclock_cpu_down_prep(unsigned int cpu) { __this_cpu_write(cpu_tsc_khz, 0); return 0; } static void tsc_khz_changed(void *data) { struct cpufreq_freqs *freq = data; unsigned long khz; WARN_ON_ONCE(boot_cpu_has(X86_FEATURE_CONSTANT_TSC)); if (data) khz = freq->new; else khz = cpufreq_quick_get(raw_smp_processor_id()); if (!khz) khz = tsc_khz; __this_cpu_write(cpu_tsc_khz, khz); } #ifdef CONFIG_X86_64 static void kvm_hyperv_tsc_notifier(void) { struct kvm *kvm; int cpu; mutex_lock(&kvm_lock); list_for_each_entry(kvm, &vm_list, vm_list) kvm_make_mclock_inprogress_request(kvm); /* no guest entries from this point */ hyperv_stop_tsc_emulation(); /* TSC frequency always matches when on Hyper-V */ if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) { for_each_present_cpu(cpu) per_cpu(cpu_tsc_khz, cpu) = tsc_khz; } kvm_caps.max_guest_tsc_khz = tsc_khz; list_for_each_entry(kvm, &vm_list, vm_list) { __kvm_start_pvclock_update(kvm); pvclock_update_vm_gtod_copy(kvm); kvm_end_pvclock_update(kvm); } mutex_unlock(&kvm_lock); } #endif static void __kvmclock_cpufreq_notifier(struct cpufreq_freqs *freq, int cpu) { struct kvm *kvm; struct kvm_vcpu *vcpu; int send_ipi = 0; unsigned long i; /* * We allow guests to temporarily run on slowing clocks, * provided we notify them after, or to run on accelerating * clocks, provided we notify them before. Thus time never * goes backwards. * * However, we have a problem. We can't atomically update * the frequency of a given CPU from this function; it is * merely a notifier, which can be called from any CPU. * Changing the TSC frequency at arbitrary points in time * requires a recomputation of local variables related to * the TSC for each VCPU. We must flag these local variables * to be updated and be sure the update takes place with the * new frequency before any guests proceed. * * Unfortunately, the combination of hotplug CPU and frequency * change creates an intractable locking scenario; the order * of when these callouts happen is undefined with respect to * CPU hotplug, and they can race with each other. As such, * merely setting per_cpu(cpu_tsc_khz) = X during a hotadd is * undefined; you can actually have a CPU frequency change take * place in between the computation of X and the setting of the * variable. To protect against this problem, all updates of * the per_cpu tsc_khz variable are done in an interrupt * protected IPI, and all callers wishing to update the value * must wait for a synchronous IPI to complete (which is trivial * if the caller is on the CPU already). This establishes the * necessary total order on variable updates. * * Note that because a guest time update may take place * anytime after the setting of the VCPU's request bit, the * correct TSC value must be set before the request. However, * to ensure the update actually makes it to any guest which * starts running in hardware virtualization between the set * and the acquisition of the spinlock, we must also ping the * CPU after setting the request bit. * */ smp_call_function_single(cpu, tsc_khz_changed, freq, 1); mutex_lock(&kvm_lock); list_for_each_entry(kvm, &vm_list, vm_list) { kvm_for_each_vcpu(i, vcpu, kvm) { if (vcpu->cpu != cpu) continue; kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu); if (vcpu->cpu != raw_smp_processor_id()) send_ipi = 1; } } mutex_unlock(&kvm_lock); if (freq->old < freq->new && send_ipi) { /* * We upscale the frequency. Must make the guest * doesn't see old kvmclock values while running with * the new frequency, otherwise we risk the guest sees * time go backwards. * * In case we update the frequency for another cpu * (which might be in guest context) send an interrupt * to kick the cpu out of guest context. Next time * guest context is entered kvmclock will be updated, * so the guest will not see stale values. */ smp_call_function_single(cpu, tsc_khz_changed, freq, 1); } } static int kvmclock_cpufreq_notifier(struct notifier_block *nb, unsigned long val, void *data) { struct cpufreq_freqs *freq = data; int cpu; if (val == CPUFREQ_PRECHANGE && freq->old > freq->new) return 0; if (val == CPUFREQ_POSTCHANGE && freq->old < freq->new) return 0; for_each_cpu(cpu, freq->policy->cpus) __kvmclock_cpufreq_notifier(freq, cpu); return 0; } static struct notifier_block kvmclock_cpufreq_notifier_block = { .notifier_call = kvmclock_cpufreq_notifier }; static int kvmclock_cpu_online(unsigned int cpu) { tsc_khz_changed(NULL); return 0; } static void kvm_timer_init(void) { if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) { max_tsc_khz = tsc_khz; if (IS_ENABLED(CONFIG_CPU_FREQ)) { struct cpufreq_policy *policy; int cpu; cpu = get_cpu(); policy = cpufreq_cpu_get(cpu); if (policy) { if (policy->cpuinfo.max_freq) max_tsc_khz = policy->cpuinfo.max_freq; cpufreq_cpu_put(policy); } put_cpu(); } cpufreq_register_notifier(&kvmclock_cpufreq_notifier_block, CPUFREQ_TRANSITION_NOTIFIER); cpuhp_setup_state(CPUHP_AP_X86_KVM_CLK_ONLINE, "x86/kvm/clk:online", kvmclock_cpu_online, kvmclock_cpu_down_prep); } } #ifdef CONFIG_X86_64 static void pvclock_gtod_update_fn(struct work_struct *work) { struct kvm *kvm; struct kvm_vcpu *vcpu; unsigned long i; mutex_lock(&kvm_lock); list_for_each_entry(kvm, &vm_list, vm_list) kvm_for_each_vcpu(i, vcpu, kvm) kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu); atomic_set(&kvm_guest_has_master_clock, 0); mutex_unlock(&kvm_lock); } static DECLARE_WORK(pvclock_gtod_work, pvclock_gtod_update_fn); /* * Indirection to move queue_work() out of the tk_core.seq write held * region to prevent possible deadlocks against time accessors which * are invoked with work related locks held. */ static void pvclock_irq_work_fn(struct irq_work *w) { queue_work(system_long_wq, &pvclock_gtod_work); } static DEFINE_IRQ_WORK(pvclock_irq_work, pvclock_irq_work_fn); /* * Notification about pvclock gtod data update. */ static int pvclock_gtod_notify(struct notifier_block *nb, unsigned long unused, void *priv) { struct pvclock_gtod_data *gtod = &pvclock_gtod_data; struct timekeeper *tk = priv; update_pvclock_gtod(tk); /* * Disable master clock if host does not trust, or does not use, * TSC based clocksource. Delegate queue_work() to irq_work as * this is invoked with tk_core.seq write held. */ if (!gtod_is_based_on_tsc(gtod->clock.vclock_mode) && atomic_read(&kvm_guest_has_master_clock) != 0) irq_work_queue(&pvclock_irq_work); return 0; } static struct notifier_block pvclock_gtod_notifier = { .notifier_call = pvclock_gtod_notify, }; #endif static inline void kvm_ops_update(struct kvm_x86_init_ops *ops) { memcpy(&kvm_x86_ops, ops->runtime_ops, sizeof(kvm_x86_ops)); #define __KVM_X86_OP(func) \ static_call_update(kvm_x86_##func, kvm_x86_ops.func); #define KVM_X86_OP(func) \ WARN_ON(!kvm_x86_ops.func); __KVM_X86_OP(func) #define KVM_X86_OP_OPTIONAL __KVM_X86_OP #define KVM_X86_OP_OPTIONAL_RET0(func) \ static_call_update(kvm_x86_##func, (void *)kvm_x86_ops.func ? : \ (void *)__static_call_return0); #include #undef __KVM_X86_OP kvm_pmu_ops_update(ops->pmu_ops); } static int kvm_x86_check_processor_compatibility(void) { int cpu = smp_processor_id(); struct cpuinfo_x86 *c = &cpu_data(cpu); /* * Compatibility checks are done when loading KVM and when enabling * hardware, e.g. during CPU hotplug, to ensure all online CPUs are * compatible, i.e. KVM should never perform a compatibility check on * an offline CPU. */ WARN_ON(!cpu_online(cpu)); if (__cr4_reserved_bits(cpu_has, c) != __cr4_reserved_bits(cpu_has, &boot_cpu_data)) return -EIO; return static_call(kvm_x86_check_processor_compatibility)(); } static void kvm_x86_check_cpu_compat(void *ret) { *(int *)ret = kvm_x86_check_processor_compatibility(); } int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops) { u64 host_pat; int r, cpu; guard(mutex)(&vendor_module_lock); if (kvm_x86_ops.hardware_enable) { pr_err("already loaded vendor module '%s'\n", kvm_x86_ops.name); return -EEXIST; } /* * KVM explicitly assumes that the guest has an FPU and * FXSAVE/FXRSTOR. For example, the KVM_GET_FPU explicitly casts the * vCPU's FPU state as a fxregs_state struct. */ if (!boot_cpu_has(X86_FEATURE_FPU) || !boot_cpu_has(X86_FEATURE_FXSR)) { pr_err("inadequate fpu\n"); return -EOPNOTSUPP; } if (IS_ENABLED(CONFIG_PREEMPT_RT) && !boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) { pr_err("RT requires X86_FEATURE_CONSTANT_TSC\n"); return -EOPNOTSUPP; } /* * KVM assumes that PAT entry '0' encodes WB memtype and simply zeroes * the PAT bits in SPTEs. Bail if PAT[0] is programmed to something * other than WB. Note, EPT doesn't utilize the PAT, but don't bother * with an exception. PAT[0] is set to WB on RESET and also by the * kernel, i.e. failure indicates a kernel bug or broken firmware. */ if (rdmsrl_safe(MSR_IA32_CR_PAT, &host_pat) || (host_pat & GENMASK(2, 0)) != 6) { pr_err("host PAT[0] is not WB\n"); return -EIO; } x86_emulator_cache = kvm_alloc_emulator_cache(); if (!x86_emulator_cache) { pr_err("failed to allocate cache for x86 emulator\n"); return -ENOMEM; } user_return_msrs = alloc_percpu(struct kvm_user_return_msrs); if (!user_return_msrs) { pr_err("failed to allocate percpu kvm_user_return_msrs\n"); r = -ENOMEM; goto out_free_x86_emulator_cache; } kvm_nr_uret_msrs = 0; r = kvm_mmu_vendor_module_init(); if (r) goto out_free_percpu; if (boot_cpu_has(X86_FEATURE_XSAVE)) { host_xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK); kvm_caps.supported_xcr0 = host_xcr0 & KVM_SUPPORTED_XCR0; } rdmsrl_safe(MSR_EFER, &host_efer); if (boot_cpu_has(X86_FEATURE_XSAVES)) rdmsrl(MSR_IA32_XSS, host_xss); kvm_init_pmu_capability(ops->pmu_ops); if (boot_cpu_has(X86_FEATURE_ARCH_CAPABILITIES)) rdmsrl(MSR_IA32_ARCH_CAPABILITIES, host_arch_capabilities); r = ops->hardware_setup(); if (r != 0) goto out_mmu_exit; kvm_ops_update(ops); for_each_online_cpu(cpu) { smp_call_function_single(cpu, kvm_x86_check_cpu_compat, &r, 1); if (r < 0) goto out_unwind_ops; } /* * Point of no return! DO NOT add error paths below this point unless * absolutely necessary, as most operations from this point forward * require unwinding. */ kvm_timer_init(); if (pi_inject_timer == -1) pi_inject_timer = housekeeping_enabled(HK_TYPE_TIMER); #ifdef CONFIG_X86_64 pvclock_gtod_register_notifier(&pvclock_gtod_notifier); if (hypervisor_is_type(X86_HYPER_MS_HYPERV)) set_hv_tscchange_cb(kvm_hyperv_tsc_notifier); #endif kvm_register_perf_callbacks(ops->handle_intel_pt_intr); if (!kvm_cpu_cap_has(X86_FEATURE_XSAVES)) kvm_caps.supported_xss = 0; #define __kvm_cpu_cap_has(UNUSED_, f) kvm_cpu_cap_has(f) cr4_reserved_bits = __cr4_reserved_bits(__kvm_cpu_cap_has, UNUSED_); #undef __kvm_cpu_cap_has if (kvm_caps.has_tsc_control) { /* * Make sure the user can only configure tsc_khz values that * fit into a signed integer. * A min value is not calculated because it will always * be 1 on all machines. */ u64 max = min(0x7fffffffULL, __scale_tsc(kvm_caps.max_tsc_scaling_ratio, tsc_khz)); kvm_caps.max_guest_tsc_khz = max; } kvm_caps.default_tsc_scaling_ratio = 1ULL << kvm_caps.tsc_scaling_ratio_frac_bits; kvm_init_msr_lists(); return 0; out_unwind_ops: kvm_x86_ops.hardware_enable = NULL; static_call(kvm_x86_hardware_unsetup)(); out_mmu_exit: kvm_mmu_vendor_module_exit(); out_free_percpu: free_percpu(user_return_msrs); out_free_x86_emulator_cache: kmem_cache_destroy(x86_emulator_cache); return r; } EXPORT_SYMBOL_GPL(kvm_x86_vendor_init); void kvm_x86_vendor_exit(void) { kvm_unregister_perf_callbacks(); #ifdef CONFIG_X86_64 if (hypervisor_is_type(X86_HYPER_MS_HYPERV)) clear_hv_tscchange_cb(); #endif kvm_lapic_exit(); if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) { cpufreq_unregister_notifier(&kvmclock_cpufreq_notifier_block, CPUFREQ_TRANSITION_NOTIFIER); cpuhp_remove_state_nocalls(CPUHP_AP_X86_KVM_CLK_ONLINE); } #ifdef CONFIG_X86_64 pvclock_gtod_unregister_notifier(&pvclock_gtod_notifier); irq_work_sync(&pvclock_irq_work); cancel_work_sync(&pvclock_gtod_work); #endif static_call(kvm_x86_hardware_unsetup)(); kvm_mmu_vendor_module_exit(); free_percpu(user_return_msrs); kmem_cache_destroy(x86_emulator_cache); #ifdef CONFIG_KVM_XEN static_key_deferred_flush(&kvm_xen_enabled); WARN_ON(static_branch_unlikely(&kvm_xen_enabled.key)); #endif mutex_lock(&vendor_module_lock); kvm_x86_ops.hardware_enable = NULL; mutex_unlock(&vendor_module_lock); } EXPORT_SYMBOL_GPL(kvm_x86_vendor_exit); static int __kvm_emulate_halt(struct kvm_vcpu *vcpu, int state, int reason) { /* * The vCPU has halted, e.g. executed HLT. Update the run state if the * local APIC is in-kernel, the run loop will detect the non-runnable * state and halt the vCPU. Exit to userspace if the local APIC is * managed by userspace, in which case userspace is responsible for * handling wake events. */ ++vcpu->stat.halt_exits; if (lapic_in_kernel(vcpu)) { vcpu->arch.mp_state = state; return 1; } else { vcpu->run->exit_reason = reason; return 0; } } int kvm_emulate_halt_noskip(struct kvm_vcpu *vcpu) { return __kvm_emulate_halt(vcpu, KVM_MP_STATE_HALTED, KVM_EXIT_HLT); } EXPORT_SYMBOL_GPL(kvm_emulate_halt_noskip); int kvm_emulate_halt(struct kvm_vcpu *vcpu) { int ret = kvm_skip_emulated_instruction(vcpu); /* * TODO: we might be squashing a GUESTDBG_SINGLESTEP-triggered * KVM_EXIT_DEBUG here. */ return kvm_emulate_halt_noskip(vcpu) && ret; } EXPORT_SYMBOL_GPL(kvm_emulate_halt); int kvm_emulate_ap_reset_hold(struct kvm_vcpu *vcpu) { int ret = kvm_skip_emulated_instruction(vcpu); return __kvm_emulate_halt(vcpu, KVM_MP_STATE_AP_RESET_HOLD, KVM_EXIT_AP_RESET_HOLD) && ret; } EXPORT_SYMBOL_GPL(kvm_emulate_ap_reset_hold); #ifdef CONFIG_X86_64 static int kvm_pv_clock_pairing(struct kvm_vcpu *vcpu, gpa_t paddr, unsigned long clock_type) { struct kvm_clock_pairing clock_pairing; struct timespec64 ts; u64 cycle; int ret; if (clock_type != KVM_CLOCK_PAIRING_WALLCLOCK) return -KVM_EOPNOTSUPP; /* * When tsc is in permanent catchup mode guests won't be able to use * pvclock_read_retry loop to get consistent view of pvclock */ if (vcpu->arch.tsc_always_catchup) return -KVM_EOPNOTSUPP; if (!kvm_get_walltime_and_clockread(&ts, &cycle)) return -KVM_EOPNOTSUPP; clock_pairing.sec = ts.tv_sec; clock_pairing.nsec = ts.tv_nsec; clock_pairing.tsc = kvm_read_l1_tsc(vcpu, cycle); clock_pairing.flags = 0; memset(&clock_pairing.pad, 0, sizeof(clock_pairing.pad)); ret = 0; if (kvm_write_guest(vcpu->kvm, paddr, &clock_pairing, sizeof(struct kvm_clock_pairing))) ret = -KVM_EFAULT; return ret; } #endif /* * kvm_pv_kick_cpu_op: Kick a vcpu. * * @apicid - apicid of vcpu to be kicked. */ static void kvm_pv_kick_cpu_op(struct kvm *kvm, int apicid) { /* * All other fields are unused for APIC_DM_REMRD, but may be consumed by * common code, e.g. for tracing. Defer initialization to the compiler. */ struct kvm_lapic_irq lapic_irq = { .delivery_mode = APIC_DM_REMRD, .dest_mode = APIC_DEST_PHYSICAL, .shorthand = APIC_DEST_NOSHORT, .dest_id = apicid, }; kvm_irq_delivery_to_apic(kvm, NULL, &lapic_irq, NULL); } bool kvm_apicv_activated(struct kvm *kvm) { return (READ_ONCE(kvm->arch.apicv_inhibit_reasons) == 0); } EXPORT_SYMBOL_GPL(kvm_apicv_activated); bool kvm_vcpu_apicv_activated(struct kvm_vcpu *vcpu) { ulong vm_reasons = READ_ONCE(vcpu->kvm->arch.apicv_inhibit_reasons); ulong vcpu_reasons = static_call(kvm_x86_vcpu_get_apicv_inhibit_reasons)(vcpu); return (vm_reasons | vcpu_reasons) == 0; } EXPORT_SYMBOL_GPL(kvm_vcpu_apicv_activated); static void set_or_clear_apicv_inhibit(unsigned long *inhibits, enum kvm_apicv_inhibit reason, bool set) { if (set) __set_bit(reason, inhibits); else __clear_bit(reason, inhibits); trace_kvm_apicv_inhibit_changed(reason, set, *inhibits); } static void kvm_apicv_init(struct kvm *kvm) { unsigned long *inhibits = &kvm->arch.apicv_inhibit_reasons; init_rwsem(&kvm->arch.apicv_update_lock); set_or_clear_apicv_inhibit(inhibits, APICV_INHIBIT_REASON_ABSENT, true); if (!enable_apicv) set_or_clear_apicv_inhibit(inhibits, APICV_INHIBIT_REASON_DISABLE, true); } static void kvm_sched_yield(struct kvm_vcpu *vcpu, unsigned long dest_id) { struct kvm_vcpu *target = NULL; struct kvm_apic_map *map; vcpu->stat.directed_yield_attempted++; if (single_task_running()) goto no_yield; rcu_read_lock(); map = rcu_dereference(vcpu->kvm->arch.apic_map); if (likely(map) && dest_id <= map->max_apic_id && map->phys_map[dest_id]) target = map->phys_map[dest_id]->vcpu; rcu_read_unlock(); if (!target || !READ_ONCE(target->ready)) goto no_yield; /* Ignore requests to yield to self */ if (vcpu == target) goto no_yield; if (kvm_vcpu_yield_to(target) <= 0) goto no_yield; vcpu->stat.directed_yield_successful++; no_yield: return; } static int complete_hypercall_exit(struct kvm_vcpu *vcpu) { u64 ret = vcpu->run->hypercall.ret; if (!is_64_bit_mode(vcpu)) ret = (u32)ret; kvm_rax_write(vcpu, ret); ++vcpu->stat.hypercalls; return kvm_skip_emulated_instruction(vcpu); } int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) { unsigned long nr, a0, a1, a2, a3, ret; int op_64_bit; if (kvm_xen_hypercall_enabled(vcpu->kvm)) return kvm_xen_hypercall(vcpu); if (kvm_hv_hypercall_enabled(vcpu)) return kvm_hv_hypercall(vcpu); nr = kvm_rax_read(vcpu); a0 = kvm_rbx_read(vcpu); a1 = kvm_rcx_read(vcpu); a2 = kvm_rdx_read(vcpu); a3 = kvm_rsi_read(vcpu); trace_kvm_hypercall(nr, a0, a1, a2, a3); op_64_bit = is_64_bit_hypercall(vcpu); if (!op_64_bit) { nr &= 0xFFFFFFFF; a0 &= 0xFFFFFFFF; a1 &= 0xFFFFFFFF; a2 &= 0xFFFFFFFF; a3 &= 0xFFFFFFFF; } if (static_call(kvm_x86_get_cpl)(vcpu) != 0) { ret = -KVM_EPERM; goto out; } ret = -KVM_ENOSYS; switch (nr) { case KVM_HC_VAPIC_POLL_IRQ: ret = 0; break; case KVM_HC_KICK_CPU: if (!guest_pv_has(vcpu, KVM_FEATURE_PV_UNHALT)) break; kvm_pv_kick_cpu_op(vcpu->kvm, a1); kvm_sched_yield(vcpu, a1); ret = 0; break; #ifdef CONFIG_X86_64 case KVM_HC_CLOCK_PAIRING: ret = kvm_pv_clock_pairing(vcpu, a0, a1); break; #endif case KVM_HC_SEND_IPI: if (!guest_pv_has(vcpu, KVM_FEATURE_PV_SEND_IPI)) break; ret = kvm_pv_send_ipi(vcpu->kvm, a0, a1, a2, a3, op_64_bit); break; case KVM_HC_SCHED_YIELD: if (!guest_pv_has(vcpu, KVM_FEATURE_PV_SCHED_YIELD)) break; kvm_sched_yield(vcpu, a0); ret = 0; break; case KVM_HC_MAP_GPA_RANGE: { u64 gpa = a0, npages = a1, attrs = a2; ret = -KVM_ENOSYS; if (!(vcpu->kvm->arch.hypercall_exit_enabled & (1 << KVM_HC_MAP_GPA_RANGE))) break; if (!PAGE_ALIGNED(gpa) || !npages || gpa_to_gfn(gpa) + npages <= gpa_to_gfn(gpa)) { ret = -KVM_EINVAL; break; } vcpu->run->exit_reason = KVM_EXIT_HYPERCALL; vcpu->run->hypercall.nr = KVM_HC_MAP_GPA_RANGE; vcpu->run->hypercall.args[0] = gpa; vcpu->run->hypercall.args[1] = npages; vcpu->run->hypercall.args[2] = attrs; vcpu->run->hypercall.flags = 0; if (op_64_bit) vcpu->run->hypercall.flags |= KVM_EXIT_HYPERCALL_LONG_MODE; WARN_ON_ONCE(vcpu->run->hypercall.flags & KVM_EXIT_HYPERCALL_MBZ); vcpu->arch.complete_userspace_io = complete_hypercall_exit; return 0; } default: ret = -KVM_ENOSYS; break; } out: if (!op_64_bit) ret = (u32)ret; kvm_rax_write(vcpu, ret); ++vcpu->stat.hypercalls; return kvm_skip_emulated_instruction(vcpu); } EXPORT_SYMBOL_GPL(kvm_emulate_hypercall); static int emulator_fix_hypercall(struct x86_emulate_ctxt *ctxt) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); char instruction[3]; unsigned long rip = kvm_rip_read(vcpu); /* * If the quirk is disabled, synthesize a #UD and let the guest pick up * the pieces. */ if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_FIX_HYPERCALL_INSN)) { ctxt->exception.error_code_valid = false; ctxt->exception.vector = UD_VECTOR; ctxt->have_exception = true; return X86EMUL_PROPAGATE_FAULT; } static_call(kvm_x86_patch_hypercall)(vcpu, instruction); return emulator_write_emulated(ctxt, rip, instruction, 3, &ctxt->exception); } static int dm_request_for_irq_injection(struct kvm_vcpu *vcpu) { return vcpu->run->request_interrupt_window && likely(!pic_in_kernel(vcpu->kvm)); } /* Called within kvm->srcu read side. */ static void post_kvm_run_save(struct kvm_vcpu *vcpu) { struct kvm_run *kvm_run = vcpu->run; kvm_run->if_flag = static_call(kvm_x86_get_if_flag)(vcpu); kvm_run->cr8 = kvm_get_cr8(vcpu); kvm_run->apic_base = kvm_get_apic_base(vcpu); kvm_run->ready_for_interrupt_injection = pic_in_kernel(vcpu->kvm) || kvm_vcpu_ready_for_interrupt_injection(vcpu); if (is_smm(vcpu)) kvm_run->flags |= KVM_RUN_X86_SMM; } static void update_cr8_intercept(struct kvm_vcpu *vcpu) { int max_irr, tpr; if (!kvm_x86_ops.update_cr8_intercept) return; if (!lapic_in_kernel(vcpu)) return; if (vcpu->arch.apic->apicv_active) return; if (!vcpu->arch.apic->vapic_addr) max_irr = kvm_lapic_find_highest_irr(vcpu); else max_irr = -1; if (max_irr != -1) max_irr >>= 4; tpr = kvm_lapic_get_cr8(vcpu); static_call(kvm_x86_update_cr8_intercept)(vcpu, tpr, max_irr); } int kvm_check_nested_events(struct kvm_vcpu *vcpu) { if (kvm_test_request(KVM_REQ_TRIPLE_FAULT, vcpu)) { kvm_x86_ops.nested_ops->triple_fault(vcpu); return 1; } return kvm_x86_ops.nested_ops->check_events(vcpu); } static void kvm_inject_exception(struct kvm_vcpu *vcpu) { /* * Suppress the error code if the vCPU is in Real Mode, as Real Mode * exceptions don't report error codes. The presence of an error code * is carried with the exception and only stripped when the exception * is injected as intercepted #PF VM-Exits for AMD's Paged Real Mode do * report an error code despite the CPU being in Real Mode. */ vcpu->arch.exception.has_error_code &= is_protmode(vcpu); trace_kvm_inj_exception(vcpu->arch.exception.vector, vcpu->arch.exception.has_error_code, vcpu->arch.exception.error_code, vcpu->arch.exception.injected); static_call(kvm_x86_inject_exception)(vcpu); } /* * Check for any event (interrupt or exception) that is ready to be injected, * and if there is at least one event, inject the event with the highest * priority. This handles both "pending" events, i.e. events that have never * been injected into the guest, and "injected" events, i.e. events that were * injected as part of a previous VM-Enter, but weren't successfully delivered * and need to be re-injected. * * Note, this is not guaranteed to be invoked on a guest instruction boundary, * i.e. doesn't guarantee that there's an event window in the guest. KVM must * be able to inject exceptions in the "middle" of an instruction, and so must * also be able to re-inject NMIs and IRQs in the middle of an instruction. * I.e. for exceptions and re-injected events, NOT invoking this on instruction * boundaries is necessary and correct. * * For simplicity, KVM uses a single path to inject all events (except events * that are injected directly from L1 to L2) and doesn't explicitly track * instruction boundaries for asynchronous events. However, because VM-Exits * that can occur during instruction execution typically result in KVM skipping * the instruction or injecting an exception, e.g. instruction and exception * intercepts, and because pending exceptions have higher priority than pending * interrupts, KVM still honors instruction boundaries in most scenarios. * * But, if a VM-Exit occurs during instruction execution, and KVM does NOT skip * the instruction or inject an exception, then KVM can incorrecty inject a new * asynchronous event if the event became pending after the CPU fetched the * instruction (in the guest). E.g. if a page fault (#PF, #NPF, EPT violation) * occurs and is resolved by KVM, a coincident NMI, SMI, IRQ, etc... can be * injected on the restarted instruction instead of being deferred until the * instruction completes. * * In practice, this virtualization hole is unlikely to be observed by the * guest, and even less likely to cause functional problems. To detect the * hole, the guest would have to trigger an event on a side effect of an early * phase of instruction execution, e.g. on the instruction fetch from memory. * And for it to be a functional problem, the guest would need to depend on the * ordering between that side effect, the instruction completing, _and_ the * delivery of the asynchronous event. */ static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu, bool *req_immediate_exit) { bool can_inject; int r; /* * Process nested events first, as nested VM-Exit supersedes event * re-injection. If there's an event queued for re-injection, it will * be saved into the appropriate vmc{b,s}12 fields on nested VM-Exit. */ if (is_guest_mode(vcpu)) r = kvm_check_nested_events(vcpu); else r = 0; /* * Re-inject exceptions and events *especially* if immediate entry+exit * to/from L2 is needed, as any event that has already been injected * into L2 needs to complete its lifecycle before injecting a new event. * * Don't re-inject an NMI or interrupt if there is a pending exception. * This collision arises if an exception occurred while vectoring the * injected event, KVM intercepted said exception, and KVM ultimately * determined the fault belongs to the guest and queues the exception * for injection back into the guest. * * "Injected" interrupts can also collide with pending exceptions if * userspace ignores the "ready for injection" flag and blindly queues * an interrupt. In that case, prioritizing the exception is correct, * as the exception "occurred" before the exit to userspace. Trap-like * exceptions, e.g. most #DBs, have higher priority than interrupts. * And while fault-like exceptions, e.g. #GP and #PF, are the lowest * priority, they're only generated (pended) during instruction * execution, and interrupts are recognized at instruction boundaries. * Thus a pending fault-like exception means the fault occurred on the * *previous* instruction and must be serviced prior to recognizing any * new events in order to fully complete the previous instruction. */ if (vcpu->arch.exception.injected) kvm_inject_exception(vcpu); else if (kvm_is_exception_pending(vcpu)) ; /* see above */ else if (vcpu->arch.nmi_injected) static_call(kvm_x86_inject_nmi)(vcpu); else if (vcpu->arch.interrupt.injected) static_call(kvm_x86_inject_irq)(vcpu, true); /* * Exceptions that morph to VM-Exits are handled above, and pending * exceptions on top of injected exceptions that do not VM-Exit should * either morph to #DF or, sadly, override the injected exception. */ WARN_ON_ONCE(vcpu->arch.exception.injected && vcpu->arch.exception.pending); /* * Bail if immediate entry+exit to/from the guest is needed to complete * nested VM-Enter or event re-injection so that a different pending * event can be serviced (or if KVM needs to exit to userspace). * * Otherwise, continue processing events even if VM-Exit occurred. The * VM-Exit will have cleared exceptions that were meant for L2, but * there may now be events that can be injected into L1. */ if (r < 0) goto out; /* * A pending exception VM-Exit should either result in nested VM-Exit * or force an immediate re-entry and exit to/from L2, and exception * VM-Exits cannot be injected (flag should _never_ be set). */ WARN_ON_ONCE(vcpu->arch.exception_vmexit.injected || vcpu->arch.exception_vmexit.pending); /* * New events, other than exceptions, cannot be injected if KVM needs * to re-inject a previous event. See above comments on re-injecting * for why pending exceptions get priority. */ can_inject = !kvm_event_needs_reinjection(vcpu); if (vcpu->arch.exception.pending) { /* * Fault-class exceptions, except #DBs, set RF=1 in the RFLAGS * value pushed on the stack. Trap-like exception and all #DBs * leave RF as-is (KVM follows Intel's behavior in this regard; * AMD states that code breakpoint #DBs excplitly clear RF=0). * * Note, most versions of Intel's SDM and AMD's APM incorrectly * describe the behavior of General Detect #DBs, which are * fault-like. They do _not_ set RF, a la code breakpoints. */ if (exception_type(vcpu->arch.exception.vector) == EXCPT_FAULT) __kvm_set_rflags(vcpu, kvm_get_rflags(vcpu) | X86_EFLAGS_RF); if (vcpu->arch.exception.vector == DB_VECTOR) { kvm_deliver_exception_payload(vcpu, &vcpu->arch.exception); if (vcpu->arch.dr7 & DR7_GD) { vcpu->arch.dr7 &= ~DR7_GD; kvm_update_dr7(vcpu); } } kvm_inject_exception(vcpu); vcpu->arch.exception.pending = false; vcpu->arch.exception.injected = true; can_inject = false; } /* Don't inject interrupts if the user asked to avoid doing so */ if (vcpu->guest_debug & KVM_GUESTDBG_BLOCKIRQ) return 0; /* * Finally, inject interrupt events. If an event cannot be injected * due to architectural conditions (e.g. IF=0) a window-open exit * will re-request KVM_REQ_EVENT. Sometimes however an event is pending * and can architecturally be injected, but we cannot do it right now: * an interrupt could have arrived just now and we have to inject it * as a vmexit, or there could already an event in the queue, which is * indicated by can_inject. In that case we request an immediate exit * in order to make progress and get back here for another iteration. * The kvm_x86_ops hooks communicate this by returning -EBUSY. */ #ifdef CONFIG_KVM_SMM if (vcpu->arch.smi_pending) { r = can_inject ? static_call(kvm_x86_smi_allowed)(vcpu, true) : -EBUSY; if (r < 0) goto out; if (r) { vcpu->arch.smi_pending = false; ++vcpu->arch.smi_count; enter_smm(vcpu); can_inject = false; } else static_call(kvm_x86_enable_smi_window)(vcpu); } #endif if (vcpu->arch.nmi_pending) { r = can_inject ? static_call(kvm_x86_nmi_allowed)(vcpu, true) : -EBUSY; if (r < 0) goto out; if (r) { --vcpu->arch.nmi_pending; vcpu->arch.nmi_injected = true; static_call(kvm_x86_inject_nmi)(vcpu); can_inject = false; WARN_ON(static_call(kvm_x86_nmi_allowed)(vcpu, true) < 0); } if (vcpu->arch.nmi_pending) static_call(kvm_x86_enable_nmi_window)(vcpu); } if (kvm_cpu_has_injectable_intr(vcpu)) { r = can_inject ? static_call(kvm_x86_interrupt_allowed)(vcpu, true) : -EBUSY; if (r < 0) goto out; if (r) { int irq = kvm_cpu_get_interrupt(vcpu); if (!WARN_ON_ONCE(irq == -1)) { kvm_queue_interrupt(vcpu, irq, false); static_call(kvm_x86_inject_irq)(vcpu, false); WARN_ON(static_call(kvm_x86_interrupt_allowed)(vcpu, true) < 0); } } if (kvm_cpu_has_injectable_intr(vcpu)) static_call(kvm_x86_enable_irq_window)(vcpu); } if (is_guest_mode(vcpu) && kvm_x86_ops.nested_ops->has_events && kvm_x86_ops.nested_ops->has_events(vcpu)) *req_immediate_exit = true; /* * KVM must never queue a new exception while injecting an event; KVM * is done emulating and should only propagate the to-be-injected event * to the VMCS/VMCB. Queueing a new exception can put the vCPU into an * infinite loop as KVM will bail from VM-Enter to inject the pending * exception and start the cycle all over. * * Exempt triple faults as they have special handling and won't put the * vCPU into an infinite loop. Triple fault can be queued when running * VMX without unrestricted guest, as that requires KVM to emulate Real * Mode events (see kvm_inject_realmode_interrupt()). */ WARN_ON_ONCE(vcpu->arch.exception.pending || vcpu->arch.exception_vmexit.pending); return 0; out: if (r == -EBUSY) { *req_immediate_exit = true; r = 0; } return r; } static void process_nmi(struct kvm_vcpu *vcpu) { unsigned int limit; /* * x86 is limited to one NMI pending, but because KVM can't react to * incoming NMIs as quickly as bare metal, e.g. if the vCPU is * scheduled out, KVM needs to play nice with two queued NMIs showing * up at the same time. To handle this scenario, allow two NMIs to be * (temporarily) pending so long as NMIs are not blocked and KVM is not * waiting for a previous NMI injection to complete (which effectively * blocks NMIs). KVM will immediately inject one of the two NMIs, and * will request an NMI window to handle the second NMI. */ if (static_call(kvm_x86_get_nmi_mask)(vcpu) || vcpu->arch.nmi_injected) limit = 1; else limit = 2; /* * Adjust the limit to account for pending virtual NMIs, which aren't * tracked in vcpu->arch.nmi_pending. */ if (static_call(kvm_x86_is_vnmi_pending)(vcpu)) limit--; vcpu->arch.nmi_pending += atomic_xchg(&vcpu->arch.nmi_queued, 0); vcpu->arch.nmi_pending = min(vcpu->arch.nmi_pending, limit); if (vcpu->arch.nmi_pending && (static_call(kvm_x86_set_vnmi_pending)(vcpu))) vcpu->arch.nmi_pending--; if (vcpu->arch.nmi_pending) kvm_make_request(KVM_REQ_EVENT, vcpu); } /* Return total number of NMIs pending injection to the VM */ int kvm_get_nr_pending_nmis(struct kvm_vcpu *vcpu) { return vcpu->arch.nmi_pending + static_call(kvm_x86_is_vnmi_pending)(vcpu); } void kvm_make_scan_ioapic_request_mask(struct kvm *kvm, unsigned long *vcpu_bitmap) { kvm_make_vcpus_request_mask(kvm, KVM_REQ_SCAN_IOAPIC, vcpu_bitmap); } void kvm_make_scan_ioapic_request(struct kvm *kvm) { kvm_make_all_cpus_request(kvm, KVM_REQ_SCAN_IOAPIC); } void __kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu) { struct kvm_lapic *apic = vcpu->arch.apic; bool activate; if (!lapic_in_kernel(vcpu)) return; down_read(&vcpu->kvm->arch.apicv_update_lock); preempt_disable(); /* Do not activate APICV when APIC is disabled */ activate = kvm_vcpu_apicv_activated(vcpu) && (kvm_get_apic_mode(vcpu) != LAPIC_MODE_DISABLED); if (apic->apicv_active == activate) goto out; apic->apicv_active = activate; kvm_apic_update_apicv(vcpu); static_call(kvm_x86_refresh_apicv_exec_ctrl)(vcpu); /* * When APICv gets disabled, we may still have injected interrupts * pending. At the same time, KVM_REQ_EVENT may not be set as APICv was * still active when the interrupt got accepted. Make sure * kvm_check_and_inject_events() is called to check for that. */ if (!apic->apicv_active) kvm_make_request(KVM_REQ_EVENT, vcpu); out: preempt_enable(); up_read(&vcpu->kvm->arch.apicv_update_lock); } EXPORT_SYMBOL_GPL(__kvm_vcpu_update_apicv); static void kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu) { if (!lapic_in_kernel(vcpu)) return; /* * Due to sharing page tables across vCPUs, the xAPIC memslot must be * deleted if any vCPU has xAPIC virtualization and x2APIC enabled, but * and hardware doesn't support x2APIC virtualization. E.g. some AMD * CPUs support AVIC but not x2APIC. KVM still allows enabling AVIC in * this case so that KVM can the AVIC doorbell to inject interrupts to * running vCPUs, but KVM must not create SPTEs for the APIC base as * the vCPU would incorrectly be able to access the vAPIC page via MMIO * despite being in x2APIC mode. For simplicity, inhibiting the APIC * access page is sticky. */ if (apic_x2apic_mode(vcpu->arch.apic) && kvm_x86_ops.allow_apicv_in_x2apic_without_x2apic_virtualization) kvm_inhibit_apic_access_page(vcpu); __kvm_vcpu_update_apicv(vcpu); } void __kvm_set_or_clear_apicv_inhibit(struct kvm *kvm, enum kvm_apicv_inhibit reason, bool set) { unsigned long old, new; lockdep_assert_held_write(&kvm->arch.apicv_update_lock); if (!(kvm_x86_ops.required_apicv_inhibits & BIT(reason))) return; old = new = kvm->arch.apicv_inhibit_reasons; set_or_clear_apicv_inhibit(&new, reason, set); if (!!old != !!new) { /* * Kick all vCPUs before setting apicv_inhibit_reasons to avoid * false positives in the sanity check WARN in svm_vcpu_run(). * This task will wait for all vCPUs to ack the kick IRQ before * updating apicv_inhibit_reasons, and all other vCPUs will * block on acquiring apicv_update_lock so that vCPUs can't * redo svm_vcpu_run() without seeing the new inhibit state. * * Note, holding apicv_update_lock and taking it in the read * side (handling the request) also prevents other vCPUs from * servicing the request with a stale apicv_inhibit_reasons. */ kvm_make_all_cpus_request(kvm, KVM_REQ_APICV_UPDATE); kvm->arch.apicv_inhibit_reasons = new; if (new) { unsigned long gfn = gpa_to_gfn(APIC_DEFAULT_PHYS_BASE); int idx = srcu_read_lock(&kvm->srcu); kvm_zap_gfn_range(kvm, gfn, gfn+1); srcu_read_unlock(&kvm->srcu, idx); } } else { kvm->arch.apicv_inhibit_reasons = new; } } void kvm_set_or_clear_apicv_inhibit(struct kvm *kvm, enum kvm_apicv_inhibit reason, bool set) { if (!enable_apicv) return; down_write(&kvm->arch.apicv_update_lock); __kvm_set_or_clear_apicv_inhibit(kvm, reason, set); up_write(&kvm->arch.apicv_update_lock); } EXPORT_SYMBOL_GPL(kvm_set_or_clear_apicv_inhibit); static void vcpu_scan_ioapic(struct kvm_vcpu *vcpu) { if (!kvm_apic_present(vcpu)) return; bitmap_zero(vcpu->arch.ioapic_handled_vectors, 256); if (irqchip_split(vcpu->kvm)) kvm_scan_ioapic_routes(vcpu, vcpu->arch.ioapic_handled_vectors); else { static_call_cond(kvm_x86_sync_pir_to_irr)(vcpu); if (ioapic_in_kernel(vcpu->kvm)) kvm_ioapic_scan_entry(vcpu, vcpu->arch.ioapic_handled_vectors); } if (is_guest_mode(vcpu)) vcpu->arch.load_eoi_exitmap_pending = true; else kvm_make_request(KVM_REQ_LOAD_EOI_EXITMAP, vcpu); } static void vcpu_load_eoi_exitmap(struct kvm_vcpu *vcpu) { if (!kvm_apic_hw_enabled(vcpu->arch.apic)) return; #ifdef CONFIG_KVM_HYPERV if (to_hv_vcpu(vcpu)) { u64 eoi_exit_bitmap[4]; bitmap_or((ulong *)eoi_exit_bitmap, vcpu->arch.ioapic_handled_vectors, to_hv_synic(vcpu)->vec_bitmap, 256); static_call_cond(kvm_x86_load_eoi_exitmap)(vcpu, eoi_exit_bitmap); return; } #endif static_call_cond(kvm_x86_load_eoi_exitmap)( vcpu, (u64 *)vcpu->arch.ioapic_handled_vectors); } void kvm_arch_guest_memory_reclaimed(struct kvm *kvm) { static_call_cond(kvm_x86_guest_memory_reclaimed)(kvm); } static void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu) { if (!lapic_in_kernel(vcpu)) return; static_call_cond(kvm_x86_set_apic_access_page_addr)(vcpu); } /* * Called within kvm->srcu read side. * Returns 1 to let vcpu_run() continue the guest execution loop without * exiting to the userspace. Otherwise, the value will be returned to the * userspace. */ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) { int r; bool req_int_win = dm_request_for_irq_injection(vcpu) && kvm_cpu_accept_dm_intr(vcpu); fastpath_t exit_fastpath; bool req_immediate_exit = false; if (kvm_request_pending(vcpu)) { if (kvm_check_request(KVM_REQ_VM_DEAD, vcpu)) { r = -EIO; goto out; } if (kvm_dirty_ring_check_request(vcpu)) { r = 0; goto out; } if (kvm_check_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu)) { if (unlikely(!kvm_x86_ops.nested_ops->get_nested_state_pages(vcpu))) { r = 0; goto out; } } if (kvm_check_request(KVM_REQ_MMU_FREE_OBSOLETE_ROOTS, vcpu)) kvm_mmu_free_obsolete_roots(vcpu); if (kvm_check_request(KVM_REQ_MIGRATE_TIMER, vcpu)) __kvm_migrate_timers(vcpu); if (kvm_check_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu)) kvm_update_masterclock(vcpu->kvm); if (kvm_check_request(KVM_REQ_GLOBAL_CLOCK_UPDATE, vcpu)) kvm_gen_kvmclock_update(vcpu); if (kvm_check_request(KVM_REQ_CLOCK_UPDATE, vcpu)) { r = kvm_guest_time_update(vcpu); if (unlikely(r)) goto out; } if (kvm_check_request(KVM_REQ_MMU_SYNC, vcpu)) kvm_mmu_sync_roots(vcpu); if (kvm_check_request(KVM_REQ_LOAD_MMU_PGD, vcpu)) kvm_mmu_load_pgd(vcpu); /* * Note, the order matters here, as flushing "all" TLB entries * also flushes the "current" TLB entries, i.e. servicing the * flush "all" will clear any request to flush "current". */ if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu)) kvm_vcpu_flush_tlb_all(vcpu); kvm_service_local_tlb_flush_requests(vcpu); /* * Fall back to a "full" guest flush if Hyper-V's precise * flushing fails. Note, Hyper-V's flushing is per-vCPU, but * the flushes are considered "remote" and not "local" because * the requests can be initiated from other vCPUs. */ #ifdef CONFIG_KVM_HYPERV if (kvm_check_request(KVM_REQ_HV_TLB_FLUSH, vcpu) && kvm_hv_vcpu_flush_tlb(vcpu)) kvm_vcpu_flush_tlb_guest(vcpu); #endif if (kvm_check_request(KVM_REQ_REPORT_TPR_ACCESS, vcpu)) { vcpu->run->exit_reason = KVM_EXIT_TPR_ACCESS; r = 0; goto out; } if (kvm_test_request(KVM_REQ_TRIPLE_FAULT, vcpu)) { if (is_guest_mode(vcpu)) kvm_x86_ops.nested_ops->triple_fault(vcpu); if (kvm_check_request(KVM_REQ_TRIPLE_FAULT, vcpu)) { vcpu->run->exit_reason = KVM_EXIT_SHUTDOWN; vcpu->mmio_needed = 0; r = 0; goto out; } } if (kvm_check_request(KVM_REQ_APF_HALT, vcpu)) { /* Page is swapped out. Do synthetic halt */ vcpu->arch.apf.halted = true; r = 1; goto out; } if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu)) record_steal_time(vcpu); if (kvm_check_request(KVM_REQ_PMU, vcpu)) kvm_pmu_handle_event(vcpu); if (kvm_check_request(KVM_REQ_PMI, vcpu)) kvm_pmu_deliver_pmi(vcpu); #ifdef CONFIG_KVM_SMM if (kvm_check_request(KVM_REQ_SMI, vcpu)) process_smi(vcpu); #endif if (kvm_check_request(KVM_REQ_NMI, vcpu)) process_nmi(vcpu); if (kvm_check_request(KVM_REQ_IOAPIC_EOI_EXIT, vcpu)) { BUG_ON(vcpu->arch.pending_ioapic_eoi > 255); if (test_bit(vcpu->arch.pending_ioapic_eoi, vcpu->arch.ioapic_handled_vectors)) { vcpu->run->exit_reason = KVM_EXIT_IOAPIC_EOI; vcpu->run->eoi.vector = vcpu->arch.pending_ioapic_eoi; r = 0; goto out; } } if (kvm_check_request(KVM_REQ_SCAN_IOAPIC, vcpu)) vcpu_scan_ioapic(vcpu); if (kvm_check_request(KVM_REQ_LOAD_EOI_EXITMAP, vcpu)) vcpu_load_eoi_exitmap(vcpu); if (kvm_check_request(KVM_REQ_APIC_PAGE_RELOAD, vcpu)) kvm_vcpu_reload_apic_access_page(vcpu); #ifdef CONFIG_KVM_HYPERV if (kvm_check_request(KVM_REQ_HV_CRASH, vcpu)) { vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; vcpu->run->system_event.type = KVM_SYSTEM_EVENT_CRASH; vcpu->run->system_event.ndata = 0; r = 0; goto out; } if (kvm_check_request(KVM_REQ_HV_RESET, vcpu)) { vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; vcpu->run->system_event.type = KVM_SYSTEM_EVENT_RESET; vcpu->run->system_event.ndata = 0; r = 0; goto out; } if (kvm_check_request(KVM_REQ_HV_EXIT, vcpu)) { struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu); vcpu->run->exit_reason = KVM_EXIT_HYPERV; vcpu->run->hyperv = hv_vcpu->exit; r = 0; goto out; } /* * KVM_REQ_HV_STIMER has to be processed after * KVM_REQ_CLOCK_UPDATE, because Hyper-V SynIC timers * depend on the guest clock being up-to-date */ if (kvm_check_request(KVM_REQ_HV_STIMER, vcpu)) kvm_hv_process_stimers(vcpu); #endif if (kvm_check_request(KVM_REQ_APICV_UPDATE, vcpu)) kvm_vcpu_update_apicv(vcpu); if (kvm_check_request(KVM_REQ_APF_READY, vcpu)) kvm_check_async_pf_completion(vcpu); if (kvm_check_request(KVM_REQ_MSR_FILTER_CHANGED, vcpu)) static_call(kvm_x86_msr_filter_changed)(vcpu); if (kvm_check_request(KVM_REQ_UPDATE_CPU_DIRTY_LOGGING, vcpu)) static_call(kvm_x86_update_cpu_dirty_logging)(vcpu); } if (kvm_check_request(KVM_REQ_EVENT, vcpu) || req_int_win || kvm_xen_has_interrupt(vcpu)) { ++vcpu->stat.req_event; r = kvm_apic_accept_events(vcpu); if (r < 0) { r = 0; goto out; } if (vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED) { r = 1; goto out; } r = kvm_check_and_inject_events(vcpu, &req_immediate_exit); if (r < 0) { r = 0; goto out; } if (req_int_win) static_call(kvm_x86_enable_irq_window)(vcpu); if (kvm_lapic_enabled(vcpu)) { update_cr8_intercept(vcpu); kvm_lapic_sync_to_vapic(vcpu); } } r = kvm_mmu_reload(vcpu); if (unlikely(r)) { goto cancel_injection; } preempt_disable(); static_call(kvm_x86_prepare_switch_to_guest)(vcpu); /* * Disable IRQs before setting IN_GUEST_MODE. Posted interrupt * IPI are then delayed after guest entry, which ensures that they * result in virtual interrupt delivery. */ local_irq_disable(); /* Store vcpu->apicv_active before vcpu->mode. */ smp_store_release(&vcpu->mode, IN_GUEST_MODE); kvm_vcpu_srcu_read_unlock(vcpu); /* * 1) We should set ->mode before checking ->requests. Please see * the comment in kvm_vcpu_exiting_guest_mode(). * * 2) For APICv, we should set ->mode before checking PID.ON. This * pairs with the memory barrier implicit in pi_test_and_set_on * (see vmx_deliver_posted_interrupt). * * 3) This also orders the write to mode from any reads to the page * tables done while the VCPU is running. Please see the comment * in kvm_flush_remote_tlbs. */ smp_mb__after_srcu_read_unlock(); /* * Process pending posted interrupts to handle the case where the * notification IRQ arrived in the host, or was never sent (because the * target vCPU wasn't running). Do this regardless of the vCPU's APICv * status, KVM doesn't update assigned devices when APICv is inhibited, * i.e. they can post interrupts even if APICv is temporarily disabled. */ if (kvm_lapic_enabled(vcpu)) static_call_cond(kvm_x86_sync_pir_to_irr)(vcpu); if (kvm_vcpu_exit_request(vcpu)) { vcpu->mode = OUTSIDE_GUEST_MODE; smp_wmb(); local_irq_enable(); preempt_enable(); kvm_vcpu_srcu_read_lock(vcpu); r = 1; goto cancel_injection; } if (req_immediate_exit) kvm_make_request(KVM_REQ_EVENT, vcpu); fpregs_assert_state_consistent(); if (test_thread_flag(TIF_NEED_FPU_LOAD)) switch_fpu_return(); if (vcpu->arch.guest_fpu.xfd_err) wrmsrl(MSR_IA32_XFD_ERR, vcpu->arch.guest_fpu.xfd_err); if (unlikely(vcpu->arch.switch_db_regs)) { set_debugreg(0, 7); set_debugreg(vcpu->arch.eff_db[0], 0); set_debugreg(vcpu->arch.eff_db[1], 1); set_debugreg(vcpu->arch.eff_db[2], 2); set_debugreg(vcpu->arch.eff_db[3], 3); } else if (unlikely(hw_breakpoint_active())) { set_debugreg(0, 7); } guest_timing_enter_irqoff(); for (;;) { /* * Assert that vCPU vs. VM APICv state is consistent. An APICv * update must kick and wait for all vCPUs before toggling the * per-VM state, and responding vCPUs must wait for the update * to complete before servicing KVM_REQ_APICV_UPDATE. */ WARN_ON_ONCE((kvm_vcpu_apicv_activated(vcpu) != kvm_vcpu_apicv_active(vcpu)) && (kvm_get_apic_mode(vcpu) != LAPIC_MODE_DISABLED)); exit_fastpath = static_call(kvm_x86_vcpu_run)(vcpu, req_immediate_exit); if (likely(exit_fastpath != EXIT_FASTPATH_REENTER_GUEST)) break; if (kvm_lapic_enabled(vcpu)) static_call_cond(kvm_x86_sync_pir_to_irr)(vcpu); if (unlikely(kvm_vcpu_exit_request(vcpu))) { exit_fastpath = EXIT_FASTPATH_EXIT_HANDLED; break; } /* Note, VM-Exits that go down the "slow" path are accounted below. */ ++vcpu->stat.exits; } /* * Do this here before restoring debug registers on the host. And * since we do this before handling the vmexit, a DR access vmexit * can (a) read the correct value of the debug registers, (b) set * KVM_DEBUGREG_WONT_EXIT again. */ if (unlikely(vcpu->arch.switch_db_regs & KVM_DEBUGREG_WONT_EXIT)) { WARN_ON(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP); static_call(kvm_x86_sync_dirty_debug_regs)(vcpu); kvm_update_dr0123(vcpu); kvm_update_dr7(vcpu); } /* * If the guest has used debug registers, at least dr7 * will be disabled while returning to the host. * If we don't have active breakpoints in the host, we don't * care about the messed up debug address registers. But if * we have some of them active, restore the old state. */ if (hw_breakpoint_active()) hw_breakpoint_restore(); vcpu->arch.last_vmentry_cpu = vcpu->cpu; vcpu->arch.last_guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc()); vcpu->mode = OUTSIDE_GUEST_MODE; smp_wmb(); /* * Sync xfd before calling handle_exit_irqoff() which may * rely on the fact that guest_fpu::xfd is up-to-date (e.g. * in #NM irqoff handler). */ if (vcpu->arch.xfd_no_write_intercept) fpu_sync_guest_vmexit_xfd_state(); static_call(kvm_x86_handle_exit_irqoff)(vcpu); if (vcpu->arch.guest_fpu.xfd_err) wrmsrl(MSR_IA32_XFD_ERR, 0); /* * Consume any pending interrupts, including the possible source of * VM-Exit on SVM and any ticks that occur between VM-Exit and now. * An instruction is required after local_irq_enable() to fully unblock * interrupts on processors that implement an interrupt shadow, the * stat.exits increment will do nicely. */ kvm_before_interrupt(vcpu, KVM_HANDLING_IRQ); local_irq_enable(); ++vcpu->stat.exits; local_irq_disable(); kvm_after_interrupt(vcpu); /* * Wait until after servicing IRQs to account guest time so that any * ticks that occurred while running the guest are properly accounted * to the guest. Waiting until IRQs are enabled degrades the accuracy * of accounting via context tracking, but the loss of accuracy is * acceptable for all known use cases. */ guest_timing_exit_irqoff(); local_irq_enable(); preempt_enable(); kvm_vcpu_srcu_read_lock(vcpu); /* * Profile KVM exit RIPs: */ if (unlikely(prof_on == KVM_PROFILING)) { unsigned long rip = kvm_rip_read(vcpu); profile_hit(KVM_PROFILING, (void *)rip); } if (unlikely(vcpu->arch.tsc_always_catchup)) kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu); if (vcpu->arch.apic_attention) kvm_lapic_sync_from_vapic(vcpu); r = static_call(kvm_x86_handle_exit)(vcpu, exit_fastpath); return r; cancel_injection: if (req_immediate_exit) kvm_make_request(KVM_REQ_EVENT, vcpu); static_call(kvm_x86_cancel_injection)(vcpu); if (unlikely(vcpu->arch.apic_attention)) kvm_lapic_sync_from_vapic(vcpu); out: return r; } /* Called within kvm->srcu read side. */ static inline int vcpu_block(struct kvm_vcpu *vcpu) { bool hv_timer; if (!kvm_arch_vcpu_runnable(vcpu)) { /* * Switch to the software timer before halt-polling/blocking as * the guest's timer may be a break event for the vCPU, and the * hypervisor timer runs only when the CPU is in guest mode. * Switch before halt-polling so that KVM recognizes an expired * timer before blocking. */ hv_timer = kvm_lapic_hv_timer_in_use(vcpu); if (hv_timer) kvm_lapic_switch_to_sw_timer(vcpu); kvm_vcpu_srcu_read_unlock(vcpu); if (vcpu->arch.mp_state == KVM_MP_STATE_HALTED) kvm_vcpu_halt(vcpu); else kvm_vcpu_block(vcpu); kvm_vcpu_srcu_read_lock(vcpu); if (hv_timer) kvm_lapic_switch_to_hv_timer(vcpu); /* * If the vCPU is not runnable, a signal or another host event * of some kind is pending; service it without changing the * vCPU's activity state. */ if (!kvm_arch_vcpu_runnable(vcpu)) return 1; } /* * Evaluate nested events before exiting the halted state. This allows * the halt state to be recorded properly in the VMCS12's activity * state field (AMD does not have a similar field and a VM-Exit always * causes a spurious wakeup from HLT). */ if (is_guest_mode(vcpu)) { if (kvm_check_nested_events(vcpu) < 0) return 0; } if (kvm_apic_accept_events(vcpu) < 0) return 0; switch(vcpu->arch.mp_state) { case KVM_MP_STATE_HALTED: case KVM_MP_STATE_AP_RESET_HOLD: vcpu->arch.pv.pv_unhalted = false; vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE; fallthrough; case KVM_MP_STATE_RUNNABLE: vcpu->arch.apf.halted = false; break; case KVM_MP_STATE_INIT_RECEIVED: break; default: WARN_ON_ONCE(1); break; } return 1; } static inline bool kvm_vcpu_running(struct kvm_vcpu *vcpu) { return (vcpu->arch.mp_state == KVM_MP_STATE_RUNNABLE && !vcpu->arch.apf.halted); } /* Called within kvm->srcu read side. */ static int vcpu_run(struct kvm_vcpu *vcpu) { int r; vcpu->run->exit_reason = KVM_EXIT_UNKNOWN; vcpu->arch.l1tf_flush_l1d = true; for (;;) { /* * If another guest vCPU requests a PV TLB flush in the middle * of instruction emulation, the rest of the emulation could * use a stale page translation. Assume that any code after * this point can start executing an instruction. */ vcpu->arch.at_instruction_boundary = false; if (kvm_vcpu_running(vcpu)) { r = vcpu_enter_guest(vcpu); } else { r = vcpu_block(vcpu); } if (r <= 0) break; kvm_clear_request(KVM_REQ_UNBLOCK, vcpu); if (kvm_xen_has_pending_events(vcpu)) kvm_xen_inject_pending_events(vcpu); if (kvm_cpu_has_pending_timer(vcpu)) kvm_inject_pending_timer_irqs(vcpu); if (dm_request_for_irq_injection(vcpu) && kvm_vcpu_ready_for_interrupt_injection(vcpu)) { r = 0; vcpu->run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN; ++vcpu->stat.request_irq_exits; break; } if (__xfer_to_guest_mode_work_pending()) { kvm_vcpu_srcu_read_unlock(vcpu); r = xfer_to_guest_mode_handle_work(vcpu); kvm_vcpu_srcu_read_lock(vcpu); if (r) return r; } } return r; } static inline int complete_emulated_io(struct kvm_vcpu *vcpu) { return kvm_emulate_instruction(vcpu, EMULTYPE_NO_DECODE); } static int complete_emulated_pio(struct kvm_vcpu *vcpu) { BUG_ON(!vcpu->arch.pio.count); return complete_emulated_io(vcpu); } /* * Implements the following, as a state machine: * * read: * for each fragment * for each mmio piece in the fragment * write gpa, len * exit * copy data * execute insn * * write: * for each fragment * for each mmio piece in the fragment * write gpa, len * copy data * exit */ static int complete_emulated_mmio(struct kvm_vcpu *vcpu) { struct kvm_run *run = vcpu->run; struct kvm_mmio_fragment *frag; unsigned len; BUG_ON(!vcpu->mmio_needed); /* Complete previous fragment */ frag = &vcpu->mmio_fragments[vcpu->mmio_cur_fragment]; len = min(8u, frag->len); if (!vcpu->mmio_is_write) memcpy(frag->data, run->mmio.data, len); if (frag->len <= 8) { /* Switch to the next fragment. */ frag++; vcpu->mmio_cur_fragment++; } else { /* Go forward to the next mmio piece. */ frag->data += len; frag->gpa += len; frag->len -= len; } if (vcpu->mmio_cur_fragment >= vcpu->mmio_nr_fragments) { vcpu->mmio_needed = 0; /* FIXME: return into emulator if single-stepping. */ if (vcpu->mmio_is_write) return 1; vcpu->mmio_read_completed = 1; return complete_emulated_io(vcpu); } run->exit_reason = KVM_EXIT_MMIO; run->mmio.phys_addr = frag->gpa; if (vcpu->mmio_is_write) memcpy(run->mmio.data, frag->data, min(8u, frag->len)); run->mmio.len = min(8u, frag->len); run->mmio.is_write = vcpu->mmio_is_write; vcpu->arch.complete_userspace_io = complete_emulated_mmio; return 0; } /* Swap (qemu) user FPU context for the guest FPU context. */ static void kvm_load_guest_fpu(struct kvm_vcpu *vcpu) { /* Exclude PKRU, it's restored separately immediately after VM-Exit. */ fpu_swap_kvm_fpstate(&vcpu->arch.guest_fpu, true); trace_kvm_fpu(1); } /* When vcpu_run ends, restore user space FPU context. */ static void kvm_put_guest_fpu(struct kvm_vcpu *vcpu) { fpu_swap_kvm_fpstate(&vcpu->arch.guest_fpu, false); ++vcpu->stat.fpu_reload; trace_kvm_fpu(0); } int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) { struct kvm_queued_exception *ex = &vcpu->arch.exception; struct kvm_run *kvm_run = vcpu->run; int r; vcpu_load(vcpu); kvm_sigset_activate(vcpu); kvm_run->flags = 0; kvm_load_guest_fpu(vcpu); kvm_vcpu_srcu_read_lock(vcpu); if (unlikely(vcpu->arch.mp_state == KVM_MP_STATE_UNINITIALIZED)) { if (kvm_run->immediate_exit) { r = -EINTR; goto out; } /* * Don't bother switching APIC timer emulation from the * hypervisor timer to the software timer, the only way for the * APIC timer to be active is if userspace stuffed vCPU state, * i.e. put the vCPU into a nonsensical state. Only an INIT * will transition the vCPU out of UNINITIALIZED (without more * state stuffing from userspace), which will reset the local * APIC and thus cancel the timer or drop the IRQ (if the timer * already expired). */ kvm_vcpu_srcu_read_unlock(vcpu); kvm_vcpu_block(vcpu); kvm_vcpu_srcu_read_lock(vcpu); if (kvm_apic_accept_events(vcpu) < 0) { r = 0; goto out; } r = -EAGAIN; if (signal_pending(current)) { r = -EINTR; kvm_run->exit_reason = KVM_EXIT_INTR; ++vcpu->stat.signal_exits; } goto out; } if ((kvm_run->kvm_valid_regs & ~KVM_SYNC_X86_VALID_FIELDS) || (kvm_run->kvm_dirty_regs & ~KVM_SYNC_X86_VALID_FIELDS)) { r = -EINVAL; goto out; } if (kvm_run->kvm_dirty_regs) { r = sync_regs(vcpu); if (r != 0) goto out; } /* re-sync apic's tpr */ if (!lapic_in_kernel(vcpu)) { if (kvm_set_cr8(vcpu, kvm_run->cr8) != 0) { r = -EINVAL; goto out; } } /* * If userspace set a pending exception and L2 is active, convert it to * a pending VM-Exit if L1 wants to intercept the exception. */ if (vcpu->arch.exception_from_userspace && is_guest_mode(vcpu) && kvm_x86_ops.nested_ops->is_exception_vmexit(vcpu, ex->vector, ex->error_code)) { kvm_queue_exception_vmexit(vcpu, ex->vector, ex->has_error_code, ex->error_code, ex->has_payload, ex->payload); ex->injected = false; ex->pending = false; } vcpu->arch.exception_from_userspace = false; if (unlikely(vcpu->arch.complete_userspace_io)) { int (*cui)(struct kvm_vcpu *) = vcpu->arch.complete_userspace_io; vcpu->arch.complete_userspace_io = NULL; r = cui(vcpu); if (r <= 0) goto out; } else { WARN_ON_ONCE(vcpu->arch.pio.count); WARN_ON_ONCE(vcpu->mmio_needed); } if (kvm_run->immediate_exit) { r = -EINTR; goto out; } r = static_call(kvm_x86_vcpu_pre_run)(vcpu); if (r <= 0) goto out; r = vcpu_run(vcpu); out: kvm_put_guest_fpu(vcpu); if (kvm_run->kvm_valid_regs) store_regs(vcpu); post_kvm_run_save(vcpu); kvm_vcpu_srcu_read_unlock(vcpu); kvm_sigset_deactivate(vcpu); vcpu_put(vcpu); return r; } static void __get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) { if (vcpu->arch.emulate_regs_need_sync_to_vcpu) { /* * We are here if userspace calls get_regs() in the middle of * instruction emulation. Registers state needs to be copied * back from emulation context to vcpu. Userspace shouldn't do * that usually, but some bad designed PV devices (vmware * backdoor interface) need this to work */ emulator_writeback_register_cache(vcpu->arch.emulate_ctxt); vcpu->arch.emulate_regs_need_sync_to_vcpu = false; } regs->rax = kvm_rax_read(vcpu); regs->rbx = kvm_rbx_read(vcpu); regs->rcx = kvm_rcx_read(vcpu); regs->rdx = kvm_rdx_read(vcpu); regs->rsi = kvm_rsi_read(vcpu); regs->rdi = kvm_rdi_read(vcpu); regs->rsp = kvm_rsp_read(vcpu); regs->rbp = kvm_rbp_read(vcpu); #ifdef CONFIG_X86_64 regs->r8 = kvm_r8_read(vcpu); regs->r9 = kvm_r9_read(vcpu); regs->r10 = kvm_r10_read(vcpu); regs->r11 = kvm_r11_read(vcpu); regs->r12 = kvm_r12_read(vcpu); regs->r13 = kvm_r13_read(vcpu); regs->r14 = kvm_r14_read(vcpu); regs->r15 = kvm_r15_read(vcpu); #endif regs->rip = kvm_rip_read(vcpu); regs->rflags = kvm_get_rflags(vcpu); } int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) { vcpu_load(vcpu); __get_regs(vcpu, regs); vcpu_put(vcpu); return 0; } static void __set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) { vcpu->arch.emulate_regs_need_sync_from_vcpu = true; vcpu->arch.emulate_regs_need_sync_to_vcpu = false; kvm_rax_write(vcpu, regs->rax); kvm_rbx_write(vcpu, regs->rbx); kvm_rcx_write(vcpu, regs->rcx); kvm_rdx_write(vcpu, regs->rdx); kvm_rsi_write(vcpu, regs->rsi); kvm_rdi_write(vcpu, regs->rdi); kvm_rsp_write(vcpu, regs->rsp); kvm_rbp_write(vcpu, regs->rbp); #ifdef CONFIG_X86_64 kvm_r8_write(vcpu, regs->r8); kvm_r9_write(vcpu, regs->r9); kvm_r10_write(vcpu, regs->r10); kvm_r11_write(vcpu, regs->r11); kvm_r12_write(vcpu, regs->r12); kvm_r13_write(vcpu, regs->r13); kvm_r14_write(vcpu, regs->r14); kvm_r15_write(vcpu, regs->r15); #endif kvm_rip_write(vcpu, regs->rip); kvm_set_rflags(vcpu, regs->rflags | X86_EFLAGS_FIXED); vcpu->arch.exception.pending = false; vcpu->arch.exception_vmexit.pending = false; kvm_make_request(KVM_REQ_EVENT, vcpu); } int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) { vcpu_load(vcpu); __set_regs(vcpu, regs); vcpu_put(vcpu); return 0; } static void __get_sregs_common(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs) { struct desc_ptr dt; if (vcpu->arch.guest_state_protected) goto skip_protected_regs; kvm_get_segment(vcpu, &sregs->cs, VCPU_SREG_CS); kvm_get_segment(vcpu, &sregs->ds, VCPU_SREG_DS); kvm_get_segment(vcpu, &sregs->es, VCPU_SREG_ES); kvm_get_segment(vcpu, &sregs->fs, VCPU_SREG_FS); kvm_get_segment(vcpu, &sregs->gs, VCPU_SREG_GS); kvm_get_segment(vcpu, &sregs->ss, VCPU_SREG_SS); kvm_get_segment(vcpu, &sregs->tr, VCPU_SREG_TR); kvm_get_segment(vcpu, &sregs->ldt, VCPU_SREG_LDTR); static_call(kvm_x86_get_idt)(vcpu, &dt); sregs->idt.limit = dt.size; sregs->idt.base = dt.address; static_call(kvm_x86_get_gdt)(vcpu, &dt); sregs->gdt.limit = dt.size; sregs->gdt.base = dt.address; sregs->cr2 = vcpu->arch.cr2; sregs->cr3 = kvm_read_cr3(vcpu); skip_protected_regs: sregs->cr0 = kvm_read_cr0(vcpu); sregs->cr4 = kvm_read_cr4(vcpu); sregs->cr8 = kvm_get_cr8(vcpu); sregs->efer = vcpu->arch.efer; sregs->apic_base = kvm_get_apic_base(vcpu); } static void __get_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs) { __get_sregs_common(vcpu, sregs); if (vcpu->arch.guest_state_protected) return; if (vcpu->arch.interrupt.injected && !vcpu->arch.interrupt.soft) set_bit(vcpu->arch.interrupt.nr, (unsigned long *)sregs->interrupt_bitmap); } static void __get_sregs2(struct kvm_vcpu *vcpu, struct kvm_sregs2 *sregs2) { int i; __get_sregs_common(vcpu, (struct kvm_sregs *)sregs2); if (vcpu->arch.guest_state_protected) return; if (is_pae_paging(vcpu)) { for (i = 0 ; i < 4 ; i++) sregs2->pdptrs[i] = kvm_pdptr_read(vcpu, i); sregs2->flags |= KVM_SREGS2_FLAGS_PDPTRS_VALID; } } int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs) { vcpu_load(vcpu); __get_sregs(vcpu, sregs); vcpu_put(vcpu); return 0; } int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, struct kvm_mp_state *mp_state) { int r; vcpu_load(vcpu); if (kvm_mpx_supported()) kvm_load_guest_fpu(vcpu); r = kvm_apic_accept_events(vcpu); if (r < 0) goto out; r = 0; if ((vcpu->arch.mp_state == KVM_MP_STATE_HALTED || vcpu->arch.mp_state == KVM_MP_STATE_AP_RESET_HOLD) && vcpu->arch.pv.pv_unhalted) mp_state->mp_state = KVM_MP_STATE_RUNNABLE; else mp_state->mp_state = vcpu->arch.mp_state; out: if (kvm_mpx_supported()) kvm_put_guest_fpu(vcpu); vcpu_put(vcpu); return r; } int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, struct kvm_mp_state *mp_state) { int ret = -EINVAL; vcpu_load(vcpu); switch (mp_state->mp_state) { case KVM_MP_STATE_UNINITIALIZED: case KVM_MP_STATE_HALTED: case KVM_MP_STATE_AP_RESET_HOLD: case KVM_MP_STATE_INIT_RECEIVED: case KVM_MP_STATE_SIPI_RECEIVED: if (!lapic_in_kernel(vcpu)) goto out; break; case KVM_MP_STATE_RUNNABLE: break; default: goto out; } /* * Pending INITs are reported using KVM_SET_VCPU_EVENTS, disallow * forcing the guest into INIT/SIPI if those events are supposed to be * blocked. KVM prioritizes SMI over INIT, so reject INIT/SIPI state * if an SMI is pending as well. */ if ((!kvm_apic_init_sipi_allowed(vcpu) || vcpu->arch.smi_pending) && (mp_state->mp_state == KVM_MP_STATE_SIPI_RECEIVED || mp_state->mp_state == KVM_MP_STATE_INIT_RECEIVED)) goto out; if (mp_state->mp_state == KVM_MP_STATE_SIPI_RECEIVED) { vcpu->arch.mp_state = KVM_MP_STATE_INIT_RECEIVED; set_bit(KVM_APIC_SIPI, &vcpu->arch.apic->pending_events); } else vcpu->arch.mp_state = mp_state->mp_state; kvm_make_request(KVM_REQ_EVENT, vcpu); ret = 0; out: vcpu_put(vcpu); return ret; } int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int idt_index, int reason, bool has_error_code, u32 error_code) { struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt; int ret; init_emulate_ctxt(vcpu); ret = emulator_task_switch(ctxt, tss_selector, idt_index, reason, has_error_code, error_code); if (ret) { vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR; vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION; vcpu->run->internal.ndata = 0; return 0; } kvm_rip_write(vcpu, ctxt->eip); kvm_set_rflags(vcpu, ctxt->eflags); return 1; } EXPORT_SYMBOL_GPL(kvm_task_switch); static bool kvm_is_valid_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs) { if ((sregs->efer & EFER_LME) && (sregs->cr0 & X86_CR0_PG)) { /* * When EFER.LME and CR0.PG are set, the processor is in * 64-bit mode (though maybe in a 32-bit code segment). * CR4.PAE and EFER.LMA must be set. */ if (!(sregs->cr4 & X86_CR4_PAE) || !(sregs->efer & EFER_LMA)) return false; if (!kvm_vcpu_is_legal_cr3(vcpu, sregs->cr3)) return false; } else { /* * Not in 64-bit mode: EFER.LMA is clear and the code * segment cannot be 64-bit. */ if (sregs->efer & EFER_LMA || sregs->cs.l) return false; } return kvm_is_valid_cr4(vcpu, sregs->cr4) && kvm_is_valid_cr0(vcpu, sregs->cr0); } static int __set_sregs_common(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs, int *mmu_reset_needed, bool update_pdptrs) { struct msr_data apic_base_msr; int idx; struct desc_ptr dt; if (!kvm_is_valid_sregs(vcpu, sregs)) return -EINVAL; apic_base_msr.data = sregs->apic_base; apic_base_msr.host_initiated = true; if (kvm_set_apic_base(vcpu, &apic_base_msr)) return -EINVAL; if (vcpu->arch.guest_state_protected) return 0; dt.size = sregs->idt.limit; dt.address = sregs->idt.base; static_call(kvm_x86_set_idt)(vcpu, &dt); dt.size = sregs->gdt.limit; dt.address = sregs->gdt.base; static_call(kvm_x86_set_gdt)(vcpu, &dt); vcpu->arch.cr2 = sregs->cr2; *mmu_reset_needed |= kvm_read_cr3(vcpu) != sregs->cr3; vcpu->arch.cr3 = sregs->cr3; kvm_register_mark_dirty(vcpu, VCPU_EXREG_CR3); static_call_cond(kvm_x86_post_set_cr3)(vcpu, sregs->cr3); kvm_set_cr8(vcpu, sregs->cr8); *mmu_reset_needed |= vcpu->arch.efer != sregs->efer; static_call(kvm_x86_set_efer)(vcpu, sregs->efer); *mmu_reset_needed |= kvm_read_cr0(vcpu) != sregs->cr0; static_call(kvm_x86_set_cr0)(vcpu, sregs->cr0); *mmu_reset_needed |= kvm_read_cr4(vcpu) != sregs->cr4; static_call(kvm_x86_set_cr4)(vcpu, sregs->cr4); if (update_pdptrs) { idx = srcu_read_lock(&vcpu->kvm->srcu); if (is_pae_paging(vcpu)) { load_pdptrs(vcpu, kvm_read_cr3(vcpu)); *mmu_reset_needed = 1; } srcu_read_unlock(&vcpu->kvm->srcu, idx); } kvm_set_segment(vcpu, &sregs->cs, VCPU_SREG_CS); kvm_set_segment(vcpu, &sregs->ds, VCPU_SREG_DS); kvm_set_segment(vcpu, &sregs->es, VCPU_SREG_ES); kvm_set_segment(vcpu, &sregs->fs, VCPU_SREG_FS); kvm_set_segment(vcpu, &sregs->gs, VCPU_SREG_GS); kvm_set_segment(vcpu, &sregs->ss, VCPU_SREG_SS); kvm_set_segment(vcpu, &sregs->tr, VCPU_SREG_TR); kvm_set_segment(vcpu, &sregs->ldt, VCPU_SREG_LDTR); update_cr8_intercept(vcpu); /* Older userspace won't unhalt the vcpu on reset. */ if (kvm_vcpu_is_bsp(vcpu) && kvm_rip_read(vcpu) == 0xfff0 && sregs->cs.selector == 0xf000 && sregs->cs.base == 0xffff0000 && !is_protmode(vcpu)) vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE; return 0; } static int __set_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs) { int pending_vec, max_bits; int mmu_reset_needed = 0; int ret = __set_sregs_common(vcpu, sregs, &mmu_reset_needed, true); if (ret) return ret; if (mmu_reset_needed) { kvm_mmu_reset_context(vcpu); kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu); } max_bits = KVM_NR_INTERRUPTS; pending_vec = find_first_bit( (const unsigned long *)sregs->interrupt_bitmap, max_bits); if (pending_vec < max_bits) { kvm_queue_interrupt(vcpu, pending_vec, false); pr_debug("Set back pending irq %d\n", pending_vec); kvm_make_request(KVM_REQ_EVENT, vcpu); } return 0; } static int __set_sregs2(struct kvm_vcpu *vcpu, struct kvm_sregs2 *sregs2) { int mmu_reset_needed = 0; bool valid_pdptrs = sregs2->flags & KVM_SREGS2_FLAGS_PDPTRS_VALID; bool pae = (sregs2->cr0 & X86_CR0_PG) && (sregs2->cr4 & X86_CR4_PAE) && !(sregs2->efer & EFER_LMA); int i, ret; if (sregs2->flags & ~KVM_SREGS2_FLAGS_PDPTRS_VALID) return -EINVAL; if (valid_pdptrs && (!pae || vcpu->arch.guest_state_protected)) return -EINVAL; ret = __set_sregs_common(vcpu, (struct kvm_sregs *)sregs2, &mmu_reset_needed, !valid_pdptrs); if (ret) return ret; if (valid_pdptrs) { for (i = 0; i < 4 ; i++) kvm_pdptr_write(vcpu, i, sregs2->pdptrs[i]); kvm_register_mark_dirty(vcpu, VCPU_EXREG_PDPTR); mmu_reset_needed = 1; vcpu->arch.pdptrs_from_userspace = true; } if (mmu_reset_needed) { kvm_mmu_reset_context(vcpu); kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu); } return 0; } int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs) { int ret; vcpu_load(vcpu); ret = __set_sregs(vcpu, sregs); vcpu_put(vcpu); return ret; } static void kvm_arch_vcpu_guestdbg_update_apicv_inhibit(struct kvm *kvm) { bool set = false; struct kvm_vcpu *vcpu; unsigned long i; if (!enable_apicv) return; down_write(&kvm->arch.apicv_update_lock); kvm_for_each_vcpu(i, vcpu, kvm) { if (vcpu->guest_debug & KVM_GUESTDBG_BLOCKIRQ) { set = true; break; } } __kvm_set_or_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_BLOCKIRQ, set); up_write(&kvm->arch.apicv_update_lock); } int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, struct kvm_guest_debug *dbg) { unsigned long rflags; int i, r; if (vcpu->arch.guest_state_protected) return -EINVAL; vcpu_load(vcpu); if (dbg->control & (KVM_GUESTDBG_INJECT_DB | KVM_GUESTDBG_INJECT_BP)) { r = -EBUSY; if (kvm_is_exception_pending(vcpu)) goto out; if (dbg->control & KVM_GUESTDBG_INJECT_DB) kvm_queue_exception(vcpu, DB_VECTOR); else kvm_queue_exception(vcpu, BP_VECTOR); } /* * Read rflags as long as potentially injected trace flags are still * filtered out. */ rflags = kvm_get_rflags(vcpu); vcpu->guest_debug = dbg->control; if (!(vcpu->guest_debug & KVM_GUESTDBG_ENABLE)) vcpu->guest_debug = 0; if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP) { for (i = 0; i < KVM_NR_DB_REGS; ++i) vcpu->arch.eff_db[i] = dbg->arch.debugreg[i]; vcpu->arch.guest_debug_dr7 = dbg->arch.debugreg[7]; } else { for (i = 0; i < KVM_NR_DB_REGS; i++) vcpu->arch.eff_db[i] = vcpu->arch.db[i]; } kvm_update_dr7(vcpu); if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) vcpu->arch.singlestep_rip = kvm_get_linear_rip(vcpu); /* * Trigger an rflags update that will inject or remove the trace * flags. */ kvm_set_rflags(vcpu, rflags); static_call(kvm_x86_update_exception_bitmap)(vcpu); kvm_arch_vcpu_guestdbg_update_apicv_inhibit(vcpu->kvm); r = 0; out: vcpu_put(vcpu); return r; } /* * Translate a guest virtual address to a guest physical address. */ int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, struct kvm_translation *tr) { unsigned long vaddr = tr->linear_address; gpa_t gpa; int idx; vcpu_load(vcpu); idx = srcu_read_lock(&vcpu->kvm->srcu); gpa = kvm_mmu_gva_to_gpa_system(vcpu, vaddr, NULL); srcu_read_unlock(&vcpu->kvm->srcu, idx); tr->physical_address = gpa; tr->valid = gpa != INVALID_GPA; tr->writeable = 1; tr->usermode = 0; vcpu_put(vcpu); return 0; } int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu) { struct fxregs_state *fxsave; if (fpstate_is_confidential(&vcpu->arch.guest_fpu)) return 0; vcpu_load(vcpu); fxsave = &vcpu->arch.guest_fpu.fpstate->regs.fxsave; memcpy(fpu->fpr, fxsave->st_space, 128); fpu->fcw = fxsave->cwd; fpu->fsw = fxsave->swd; fpu->ftwx = fxsave->twd; fpu->last_opcode = fxsave->fop; fpu->last_ip = fxsave->rip; fpu->last_dp = fxsave->rdp; memcpy(fpu->xmm, fxsave->xmm_space, sizeof(fxsave->xmm_space)); vcpu_put(vcpu); return 0; } int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu) { struct fxregs_state *fxsave; if (fpstate_is_confidential(&vcpu->arch.guest_fpu)) return 0; vcpu_load(vcpu); fxsave = &vcpu->arch.guest_fpu.fpstate->regs.fxsave; memcpy(fxsave->st_space, fpu->fpr, 128); fxsave->cwd = fpu->fcw; fxsave->swd = fpu->fsw; fxsave->twd = fpu->ftwx; fxsave->fop = fpu->last_opcode; fxsave->rip = fpu->last_ip; fxsave->rdp = fpu->last_dp; memcpy(fxsave->xmm_space, fpu->xmm, sizeof(fxsave->xmm_space)); vcpu_put(vcpu); return 0; } static void store_regs(struct kvm_vcpu *vcpu) { BUILD_BUG_ON(sizeof(struct kvm_sync_regs) > SYNC_REGS_SIZE_BYTES); if (vcpu->run->kvm_valid_regs & KVM_SYNC_X86_REGS) __get_regs(vcpu, &vcpu->run->s.regs.regs); if (vcpu->run->kvm_valid_regs & KVM_SYNC_X86_SREGS) __get_sregs(vcpu, &vcpu->run->s.regs.sregs); if (vcpu->run->kvm_valid_regs & KVM_SYNC_X86_EVENTS) kvm_vcpu_ioctl_x86_get_vcpu_events( vcpu, &vcpu->run->s.regs.events); } static int sync_regs(struct kvm_vcpu *vcpu) { if (vcpu->run->kvm_dirty_regs & KVM_SYNC_X86_REGS) { __set_regs(vcpu, &vcpu->run->s.regs.regs); vcpu->run->kvm_dirty_regs &= ~KVM_SYNC_X86_REGS; } if (vcpu->run->kvm_dirty_regs & KVM_SYNC_X86_SREGS) { struct kvm_sregs sregs = vcpu->run->s.regs.sregs; if (__set_sregs(vcpu, &sregs)) return -EINVAL; vcpu->run->kvm_dirty_regs &= ~KVM_SYNC_X86_SREGS; } if (vcpu->run->kvm_dirty_regs & KVM_SYNC_X86_EVENTS) { struct kvm_vcpu_events events = vcpu->run->s.regs.events; if (kvm_vcpu_ioctl_x86_set_vcpu_events(vcpu, &events)) return -EINVAL; vcpu->run->kvm_dirty_regs &= ~KVM_SYNC_X86_EVENTS; } return 0; } int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id) { if (kvm_check_tsc_unstable() && kvm->created_vcpus) pr_warn_once("SMP vm created on host with unstable TSC; " "guest TSC will not be reliable\n"); if (!kvm->arch.max_vcpu_ids) kvm->arch.max_vcpu_ids = KVM_MAX_VCPU_IDS; if (id >= kvm->arch.max_vcpu_ids) return -EINVAL; return static_call(kvm_x86_vcpu_precreate)(kvm); } int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) { struct page *page; int r; vcpu->arch.last_vmentry_cpu = -1; vcpu->arch.regs_avail = ~0; vcpu->arch.regs_dirty = ~0; kvm_gpc_init(&vcpu->arch.pv_time, vcpu->kvm, vcpu, KVM_HOST_USES_PFN); if (!irqchip_in_kernel(vcpu->kvm) || kvm_vcpu_is_reset_bsp(vcpu)) vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE; else vcpu->arch.mp_state = KVM_MP_STATE_UNINITIALIZED; r = kvm_mmu_create(vcpu); if (r < 0) return r; r = kvm_create_lapic(vcpu, lapic_timer_advance_ns); if (r < 0) goto fail_mmu_destroy; r = -ENOMEM; page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO); if (!page) goto fail_free_lapic; vcpu->arch.pio_data = page_address(page); vcpu->arch.mce_banks = kcalloc(KVM_MAX_MCE_BANKS * 4, sizeof(u64), GFP_KERNEL_ACCOUNT); vcpu->arch.mci_ctl2_banks = kcalloc(KVM_MAX_MCE_BANKS, sizeof(u64), GFP_KERNEL_ACCOUNT); if (!vcpu->arch.mce_banks || !vcpu->arch.mci_ctl2_banks) goto fail_free_mce_banks; vcpu->arch.mcg_cap = KVM_MAX_MCE_BANKS; if (!zalloc_cpumask_var(&vcpu->arch.wbinvd_dirty_mask, GFP_KERNEL_ACCOUNT)) goto fail_free_mce_banks; if (!alloc_emulate_ctxt(vcpu)) goto free_wbinvd_dirty_mask; if (!fpu_alloc_guest_fpstate(&vcpu->arch.guest_fpu)) { pr_err("failed to allocate vcpu's fpu\n"); goto free_emulate_ctxt; } vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu); vcpu->arch.reserved_gpa_bits = kvm_vcpu_reserved_gpa_bits_raw(vcpu); vcpu->arch.pat = MSR_IA32_CR_PAT_DEFAULT; kvm_async_pf_hash_reset(vcpu); vcpu->arch.perf_capabilities = kvm_caps.supported_perf_cap; kvm_pmu_init(vcpu); vcpu->arch.pending_external_vector = -1; vcpu->arch.preempted_in_kernel = false; #if IS_ENABLED(CONFIG_HYPERV) vcpu->arch.hv_root_tdp = INVALID_PAGE; #endif r = static_call(kvm_x86_vcpu_create)(vcpu); if (r) goto free_guest_fpu; vcpu->arch.arch_capabilities = kvm_get_arch_capabilities(); vcpu->arch.msr_platform_info = MSR_PLATFORM_INFO_CPUID_FAULT; kvm_xen_init_vcpu(vcpu); kvm_vcpu_mtrr_init(vcpu); vcpu_load(vcpu); kvm_set_tsc_khz(vcpu, vcpu->kvm->arch.default_tsc_khz); kvm_vcpu_reset(vcpu, false); kvm_init_mmu(vcpu); vcpu_put(vcpu); return 0; free_guest_fpu: fpu_free_guest_fpstate(&vcpu->arch.guest_fpu); free_emulate_ctxt: kmem_cache_free(x86_emulator_cache, vcpu->arch.emulate_ctxt); free_wbinvd_dirty_mask: free_cpumask_var(vcpu->arch.wbinvd_dirty_mask); fail_free_mce_banks: kfree(vcpu->arch.mce_banks); kfree(vcpu->arch.mci_ctl2_banks); free_page((unsigned long)vcpu->arch.pio_data); fail_free_lapic: kvm_free_lapic(vcpu); fail_mmu_destroy: kvm_mmu_destroy(vcpu); return r; } void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) { struct kvm *kvm = vcpu->kvm; if (mutex_lock_killable(&vcpu->mutex)) return; vcpu_load(vcpu); kvm_synchronize_tsc(vcpu, NULL); vcpu_put(vcpu); /* poll control enabled by default */ vcpu->arch.msr_kvm_poll_control = 1; mutex_unlock(&vcpu->mutex); if (kvmclock_periodic_sync && vcpu->vcpu_idx == 0) schedule_delayed_work(&kvm->arch.kvmclock_sync_work, KVMCLOCK_SYNC_PERIOD); } void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) { int idx; kvmclock_reset(vcpu); static_call(kvm_x86_vcpu_free)(vcpu); kmem_cache_free(x86_emulator_cache, vcpu->arch.emulate_ctxt); free_cpumask_var(vcpu->arch.wbinvd_dirty_mask); fpu_free_guest_fpstate(&vcpu->arch.guest_fpu); kvm_xen_destroy_vcpu(vcpu); kvm_hv_vcpu_uninit(vcpu); kvm_pmu_destroy(vcpu); kfree(vcpu->arch.mce_banks); kfree(vcpu->arch.mci_ctl2_banks); kvm_free_lapic(vcpu); idx = srcu_read_lock(&vcpu->kvm->srcu); kvm_mmu_destroy(vcpu); srcu_read_unlock(&vcpu->kvm->srcu, idx); free_page((unsigned long)vcpu->arch.pio_data); kvfree(vcpu->arch.cpuid_entries); } void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) { struct kvm_cpuid_entry2 *cpuid_0x1; unsigned long old_cr0 = kvm_read_cr0(vcpu); unsigned long new_cr0; /* * Several of the "set" flows, e.g. ->set_cr0(), read other registers * to handle side effects. RESET emulation hits those flows and relies * on emulated/virtualized registers, including those that are loaded * into hardware, to be zeroed at vCPU creation. Use CRs as a sentinel * to detect improper or missing initialization. */ WARN_ON_ONCE(!init_event && (old_cr0 || kvm_read_cr3(vcpu) || kvm_read_cr4(vcpu))); /* * SVM doesn't unconditionally VM-Exit on INIT and SHUTDOWN, thus it's * possible to INIT the vCPU while L2 is active. Force the vCPU back * into L1 as EFER.SVME is cleared on INIT (along with all other EFER * bits), i.e. virtualization is disabled. */ if (is_guest_mode(vcpu)) kvm_leave_nested(vcpu); kvm_lapic_reset(vcpu, init_event); WARN_ON_ONCE(is_guest_mode(vcpu) || is_smm(vcpu)); vcpu->arch.hflags = 0; vcpu->arch.smi_pending = 0; vcpu->arch.smi_count = 0; atomic_set(&vcpu->arch.nmi_queued, 0); vcpu->arch.nmi_pending = 0; vcpu->arch.nmi_injected = false; kvm_clear_interrupt_queue(vcpu); kvm_clear_exception_queue(vcpu); memset(vcpu->arch.db, 0, sizeof(vcpu->arch.db)); kvm_update_dr0123(vcpu); vcpu->arch.dr6 = DR6_ACTIVE_LOW; vcpu->arch.dr7 = DR7_FIXED_1; kvm_update_dr7(vcpu); vcpu->arch.cr2 = 0; kvm_make_request(KVM_REQ_EVENT, vcpu); vcpu->arch.apf.msr_en_val = 0; vcpu->arch.apf.msr_int_val = 0; vcpu->arch.st.msr_val = 0; kvmclock_reset(vcpu); kvm_clear_async_pf_completion_queue(vcpu); kvm_async_pf_hash_reset(vcpu); vcpu->arch.apf.halted = false; if (vcpu->arch.guest_fpu.fpstate && kvm_mpx_supported()) { struct fpstate *fpstate = vcpu->arch.guest_fpu.fpstate; /* * All paths that lead to INIT are required to load the guest's * FPU state (because most paths are buried in KVM_RUN). */ if (init_event) kvm_put_guest_fpu(vcpu); fpstate_clear_xstate_component(fpstate, XFEATURE_BNDREGS); fpstate_clear_xstate_component(fpstate, XFEATURE_BNDCSR); if (init_event) kvm_load_guest_fpu(vcpu); } if (!init_event) { vcpu->arch.smbase = 0x30000; vcpu->arch.msr_misc_features_enables = 0; vcpu->arch.ia32_misc_enable_msr = MSR_IA32_MISC_ENABLE_PEBS_UNAVAIL | MSR_IA32_MISC_ENABLE_BTS_UNAVAIL; __kvm_set_xcr(vcpu, 0, XFEATURE_MASK_FP); __kvm_set_msr(vcpu, MSR_IA32_XSS, 0, true); } /* All GPRs except RDX (handled below) are zeroed on RESET/INIT. */ memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs)); kvm_register_mark_dirty(vcpu, VCPU_REGS_RSP); /* * Fall back to KVM's default Family/Model/Stepping of 0x600 (P6/Athlon) * if no CPUID match is found. Note, it's impossible to get a match at * RESET since KVM emulates RESET before exposing the vCPU to userspace, * i.e. it's impossible for kvm_find_cpuid_entry() to find a valid entry * on RESET. But, go through the motions in case that's ever remedied. */ cpuid_0x1 = kvm_find_cpuid_entry(vcpu, 1); kvm_rdx_write(vcpu, cpuid_0x1 ? cpuid_0x1->eax : 0x600); static_call(kvm_x86_vcpu_reset)(vcpu, init_event); kvm_set_rflags(vcpu, X86_EFLAGS_FIXED); kvm_rip_write(vcpu, 0xfff0); vcpu->arch.cr3 = 0; kvm_register_mark_dirty(vcpu, VCPU_EXREG_CR3); /* * CR0.CD/NW are set on RESET, preserved on INIT. Note, some versions * of Intel's SDM list CD/NW as being set on INIT, but they contradict * (or qualify) that with a footnote stating that CD/NW are preserved. */ new_cr0 = X86_CR0_ET; if (init_event) new_cr0 |= (old_cr0 & (X86_CR0_NW | X86_CR0_CD)); else new_cr0 |= X86_CR0_NW | X86_CR0_CD; static_call(kvm_x86_set_cr0)(vcpu, new_cr0); static_call(kvm_x86_set_cr4)(vcpu, 0); static_call(kvm_x86_set_efer)(vcpu, 0); static_call(kvm_x86_update_exception_bitmap)(vcpu); /* * On the standard CR0/CR4/EFER modification paths, there are several * complex conditions determining whether the MMU has to be reset and/or * which PCIDs have to be flushed. However, CR0.WP and the paging-related * bits in CR4 and EFER are irrelevant if CR0.PG was '0'; and a reset+flush * is needed anyway if CR0.PG was '1' (which can only happen for INIT, as * CR0 will be '0' prior to RESET). So we only need to check CR0.PG here. */ if (old_cr0 & X86_CR0_PG) { kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu); kvm_mmu_reset_context(vcpu); } /* * Intel's SDM states that all TLB entries are flushed on INIT. AMD's * APM states the TLBs are untouched by INIT, but it also states that * the TLBs are flushed on "External initialization of the processor." * Flush the guest TLB regardless of vendor, there is no meaningful * benefit in relying on the guest to flush the TLB immediately after * INIT. A spurious TLB flush is benign and likely negligible from a * performance perspective. */ if (init_event) kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu); } EXPORT_SYMBOL_GPL(kvm_vcpu_reset); void kvm_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector) { struct kvm_segment cs; kvm_get_segment(vcpu, &cs, VCPU_SREG_CS); cs.selector = vector << 8; cs.base = vector << 12; kvm_set_segment(vcpu, &cs, VCPU_SREG_CS); kvm_rip_write(vcpu, 0); } EXPORT_SYMBOL_GPL(kvm_vcpu_deliver_sipi_vector); int kvm_arch_hardware_enable(void) { struct kvm *kvm; struct kvm_vcpu *vcpu; unsigned long i; int ret; u64 local_tsc; u64 max_tsc = 0; bool stable, backwards_tsc = false; kvm_user_return_msr_cpu_online(); ret = kvm_x86_check_processor_compatibility(); if (ret) return ret; ret = static_call(kvm_x86_hardware_enable)(); if (ret != 0) return ret; local_tsc = rdtsc(); stable = !kvm_check_tsc_unstable(); list_for_each_entry(kvm, &vm_list, vm_list) { kvm_for_each_vcpu(i, vcpu, kvm) { if (!stable && vcpu->cpu == smp_processor_id()) kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu); if (stable && vcpu->arch.last_host_tsc > local_tsc) { backwards_tsc = true; if (vcpu->arch.last_host_tsc > max_tsc) max_tsc = vcpu->arch.last_host_tsc; } } } /* * Sometimes, even reliable TSCs go backwards. This happens on * platforms that reset TSC during suspend or hibernate actions, but * maintain synchronization. We must compensate. Fortunately, we can * detect that condition here, which happens early in CPU bringup, * before any KVM threads can be running. Unfortunately, we can't * bring the TSCs fully up to date with real time, as we aren't yet far * enough into CPU bringup that we know how much real time has actually * elapsed; our helper function, ktime_get_boottime_ns() will be using boot * variables that haven't been updated yet. * * So we simply find the maximum observed TSC above, then record the * adjustment to TSC in each VCPU. When the VCPU later gets loaded, * the adjustment will be applied. Note that we accumulate * adjustments, in case multiple suspend cycles happen before some VCPU * gets a chance to run again. In the event that no KVM threads get a * chance to run, we will miss the entire elapsed period, as we'll have * reset last_host_tsc, so VCPUs will not have the TSC adjusted and may * loose cycle time. This isn't too big a deal, since the loss will be * uniform across all VCPUs (not to mention the scenario is extremely * unlikely). It is possible that a second hibernate recovery happens * much faster than a first, causing the observed TSC here to be * smaller; this would require additional padding adjustment, which is * why we set last_host_tsc to the local tsc observed here. * * N.B. - this code below runs only on platforms with reliable TSC, * as that is the only way backwards_tsc is set above. Also note * that this runs for ALL vcpus, which is not a bug; all VCPUs should * have the same delta_cyc adjustment applied if backwards_tsc * is detected. Note further, this adjustment is only done once, * as we reset last_host_tsc on all VCPUs to stop this from being * called multiple times (one for each physical CPU bringup). * * Platforms with unreliable TSCs don't have to deal with this, they * will be compensated by the logic in vcpu_load, which sets the TSC to * catchup mode. This will catchup all VCPUs to real time, but cannot * guarantee that they stay in perfect synchronization. */ if (backwards_tsc) { u64 delta_cyc = max_tsc - local_tsc; list_for_each_entry(kvm, &vm_list, vm_list) { kvm->arch.backwards_tsc_observed = true; kvm_for_each_vcpu(i, vcpu, kvm) { vcpu->arch.tsc_offset_adjustment += delta_cyc; vcpu->arch.last_host_tsc = local_tsc; kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu); } /* * We have to disable TSC offset matching.. if you were * booting a VM while issuing an S4 host suspend.... * you may have some problem. Solving this issue is * left as an exercise to the reader. */ kvm->arch.last_tsc_nsec = 0; kvm->arch.last_tsc_write = 0; } } return 0; } void kvm_arch_hardware_disable(void) { static_call(kvm_x86_hardware_disable)(); drop_user_return_notifiers(); } bool kvm_vcpu_is_reset_bsp(struct kvm_vcpu *vcpu) { return vcpu->kvm->arch.bsp_vcpu_id == vcpu->vcpu_id; } bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu) { return (vcpu->arch.apic_base & MSR_IA32_APICBASE_BSP) != 0; } void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) { struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); vcpu->arch.l1tf_flush_l1d = true; if (pmu->version && unlikely(pmu->event_count)) { pmu->need_cleanup = true; kvm_make_request(KVM_REQ_PMU, vcpu); } static_call(kvm_x86_sched_in)(vcpu, cpu); } void kvm_arch_free_vm(struct kvm *kvm) { #if IS_ENABLED(CONFIG_HYPERV) kfree(kvm->arch.hv_pa_pg); #endif __kvm_arch_free_vm(kvm); } int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) { int ret; unsigned long flags; if (!kvm_is_vm_type_supported(type)) return -EINVAL; kvm->arch.vm_type = type; ret = kvm_page_track_init(kvm); if (ret) goto out; kvm_mmu_init_vm(kvm); ret = static_call(kvm_x86_vm_init)(kvm); if (ret) goto out_uninit_mmu; INIT_HLIST_HEAD(&kvm->arch.mask_notifier_list); atomic_set(&kvm->arch.noncoherent_dma_count, 0); /* Reserve bit 0 of irq_sources_bitmap for userspace irq source */ set_bit(KVM_USERSPACE_IRQ_SOURCE_ID, &kvm->arch.irq_sources_bitmap); /* Reserve bit 1 of irq_sources_bitmap for irqfd-resampler */ set_bit(KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID, &kvm->arch.irq_sources_bitmap); raw_spin_lock_init(&kvm->arch.tsc_write_lock); mutex_init(&kvm->arch.apic_map_lock); seqcount_raw_spinlock_init(&kvm->arch.pvclock_sc, &kvm->arch.tsc_write_lock); kvm->arch.kvmclock_offset = -get_kvmclock_base_ns(); raw_spin_lock_irqsave(&kvm->arch.tsc_write_lock, flags); pvclock_update_vm_gtod_copy(kvm); raw_spin_unlock_irqrestore(&kvm->arch.tsc_write_lock, flags); kvm->arch.default_tsc_khz = max_tsc_khz ? : tsc_khz; kvm->arch.guest_can_read_msr_platform_info = true; kvm->arch.enable_pmu = enable_pmu; #if IS_ENABLED(CONFIG_HYPERV) spin_lock_init(&kvm->arch.hv_root_tdp_lock); kvm->arch.hv_root_tdp = INVALID_PAGE; #endif INIT_DELAYED_WORK(&kvm->arch.kvmclock_update_work, kvmclock_update_fn); INIT_DELAYED_WORK(&kvm->arch.kvmclock_sync_work, kvmclock_sync_fn); kvm_apicv_init(kvm); kvm_hv_init_vm(kvm); kvm_xen_init_vm(kvm); return 0; out_uninit_mmu: kvm_mmu_uninit_vm(kvm); kvm_page_track_cleanup(kvm); out: return ret; } int kvm_arch_post_init_vm(struct kvm *kvm) { return kvm_mmu_post_init_vm(kvm); } static void kvm_unload_vcpu_mmu(struct kvm_vcpu *vcpu) { vcpu_load(vcpu); kvm_mmu_unload(vcpu); vcpu_put(vcpu); } static void kvm_unload_vcpu_mmus(struct kvm *kvm) { unsigned long i; struct kvm_vcpu *vcpu; kvm_for_each_vcpu(i, vcpu, kvm) { kvm_clear_async_pf_completion_queue(vcpu); kvm_unload_vcpu_mmu(vcpu); } } void kvm_arch_sync_events(struct kvm *kvm) { cancel_delayed_work_sync(&kvm->arch.kvmclock_sync_work); cancel_delayed_work_sync(&kvm->arch.kvmclock_update_work); kvm_free_pit(kvm); } /** * __x86_set_memory_region: Setup KVM internal memory slot * * @kvm: the kvm pointer to the VM. * @id: the slot ID to setup. * @gpa: the GPA to install the slot (unused when @size == 0). * @size: the size of the slot. Set to zero to uninstall a slot. * * This function helps to setup a KVM internal memory slot. Specify * @size > 0 to install a new slot, while @size == 0 to uninstall a * slot. The return code can be one of the following: * * HVA: on success (uninstall will return a bogus HVA) * -errno: on error * * The caller should always use IS_ERR() to check the return value * before use. Note, the KVM internal memory slots are guaranteed to * remain valid and unchanged until the VM is destroyed, i.e., the * GPA->HVA translation will not change. However, the HVA is a user * address, i.e. its accessibility is not guaranteed, and must be * accessed via __copy_{to,from}_user(). */ void __user * __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa, u32 size) { int i, r; unsigned long hva, old_npages; struct kvm_memslots *slots = kvm_memslots(kvm); struct kvm_memory_slot *slot; /* Called with kvm->slots_lock held. */ if (WARN_ON(id >= KVM_MEM_SLOTS_NUM)) return ERR_PTR_USR(-EINVAL); slot = id_to_memslot(slots, id); if (size) { if (slot && slot->npages) return ERR_PTR_USR(-EEXIST); /* * MAP_SHARED to prevent internal slot pages from being moved * by fork()/COW. */ hva = vm_mmap(NULL, 0, size, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0); if (IS_ERR_VALUE(hva)) return (void __user *)hva; } else { if (!slot || !slot->npages) return NULL; old_npages = slot->npages; hva = slot->userspace_addr; } for (i = 0; i < kvm_arch_nr_memslot_as_ids(kvm); i++) { struct kvm_userspace_memory_region2 m; m.slot = id | (i << 16); m.flags = 0; m.guest_phys_addr = gpa; m.userspace_addr = hva; m.memory_size = size; r = __kvm_set_memory_region(kvm, &m); if (r < 0) return ERR_PTR_USR(r); } if (!size) vm_munmap(hva, old_npages * PAGE_SIZE); return (void __user *)hva; } EXPORT_SYMBOL_GPL(__x86_set_memory_region); void kvm_arch_pre_destroy_vm(struct kvm *kvm) { kvm_mmu_pre_destroy_vm(kvm); } void kvm_arch_destroy_vm(struct kvm *kvm) { if (current->mm == kvm->mm) { /* * Free memory regions allocated on behalf of userspace, * unless the memory map has changed due to process exit * or fd copying. */ mutex_lock(&kvm->slots_lock); __x86_set_memory_region(kvm, APIC_ACCESS_PAGE_PRIVATE_MEMSLOT, 0, 0); __x86_set_memory_region(kvm, IDENTITY_PAGETABLE_PRIVATE_MEMSLOT, 0, 0); __x86_set_memory_region(kvm, TSS_PRIVATE_MEMSLOT, 0, 0); mutex_unlock(&kvm->slots_lock); } kvm_unload_vcpu_mmus(kvm); static_call_cond(kvm_x86_vm_destroy)(kvm); kvm_free_msr_filter(srcu_dereference_check(kvm->arch.msr_filter, &kvm->srcu, 1)); kvm_pic_destroy(kvm); kvm_ioapic_destroy(kvm); kvm_destroy_vcpus(kvm); kvfree(rcu_dereference_check(kvm->arch.apic_map, 1)); kfree(srcu_dereference_check(kvm->arch.pmu_event_filter, &kvm->srcu, 1)); kvm_mmu_uninit_vm(kvm); kvm_page_track_cleanup(kvm); kvm_xen_destroy_vm(kvm); kvm_hv_destroy_vm(kvm); } static void memslot_rmap_free(struct kvm_memory_slot *slot) { int i; for (i = 0; i < KVM_NR_PAGE_SIZES; ++i) { kvfree(slot->arch.rmap[i]); slot->arch.rmap[i] = NULL; } } void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot) { int i; memslot_rmap_free(slot); for (i = 1; i < KVM_NR_PAGE_SIZES; ++i) { kvfree(slot->arch.lpage_info[i - 1]); slot->arch.lpage_info[i - 1] = NULL; } kvm_page_track_free_memslot(slot); } int memslot_rmap_alloc(struct kvm_memory_slot *slot, unsigned long npages) { const int sz = sizeof(*slot->arch.rmap[0]); int i; for (i = 0; i < KVM_NR_PAGE_SIZES; ++i) { int level = i + 1; int lpages = __kvm_mmu_slot_lpages(slot, npages, level); if (slot->arch.rmap[i]) continue; slot->arch.rmap[i] = __vcalloc(lpages, sz, GFP_KERNEL_ACCOUNT); if (!slot->arch.rmap[i]) { memslot_rmap_free(slot); return -ENOMEM; } } return 0; } static int kvm_alloc_memslot_metadata(struct kvm *kvm, struct kvm_memory_slot *slot) { unsigned long npages = slot->npages; int i, r; /* * Clear out the previous array pointers for the KVM_MR_MOVE case. The * old arrays will be freed by __kvm_set_memory_region() if installing * the new memslot is successful. */ memset(&slot->arch, 0, sizeof(slot->arch)); if (kvm_memslots_have_rmaps(kvm)) { r = memslot_rmap_alloc(slot, npages); if (r) return r; } for (i = 1; i < KVM_NR_PAGE_SIZES; ++i) { struct kvm_lpage_info *linfo; unsigned long ugfn; int lpages; int level = i + 1; lpages = __kvm_mmu_slot_lpages(slot, npages, level); linfo = __vcalloc(lpages, sizeof(*linfo), GFP_KERNEL_ACCOUNT); if (!linfo) goto out_free; slot->arch.lpage_info[i - 1] = linfo; if (slot->base_gfn & (KVM_PAGES_PER_HPAGE(level) - 1)) linfo[0].disallow_lpage = 1; if ((slot->base_gfn + npages) & (KVM_PAGES_PER_HPAGE(level) - 1)) linfo[lpages - 1].disallow_lpage = 1; ugfn = slot->userspace_addr >> PAGE_SHIFT; /* * If the gfn and userspace address are not aligned wrt each * other, disable large page support for this slot. */ if ((slot->base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1)) { unsigned long j; for (j = 0; j < lpages; ++j) linfo[j].disallow_lpage = 1; } } #ifdef CONFIG_KVM_GENERIC_MEMORY_ATTRIBUTES kvm_mmu_init_memslot_memory_attributes(kvm, slot); #endif if (kvm_page_track_create_memslot(kvm, slot, npages)) goto out_free; return 0; out_free: memslot_rmap_free(slot); for (i = 1; i < KVM_NR_PAGE_SIZES; ++i) { kvfree(slot->arch.lpage_info[i - 1]); slot->arch.lpage_info[i - 1] = NULL; } return -ENOMEM; } void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) { struct kvm_vcpu *vcpu; unsigned long i; /* * memslots->generation has been incremented. * mmio generation may have reached its maximum value. */ kvm_mmu_invalidate_mmio_sptes(kvm, gen); /* Force re-initialization of steal_time cache */ kvm_for_each_vcpu(i, vcpu, kvm) kvm_vcpu_kick(vcpu); } int kvm_arch_prepare_memory_region(struct kvm *kvm, const struct kvm_memory_slot *old, struct kvm_memory_slot *new, enum kvm_mr_change change) { /* * KVM doesn't support moving memslots when there are external page * trackers attached to the VM, i.e. if KVMGT is in use. */ if (change == KVM_MR_MOVE && kvm_page_track_has_external_user(kvm)) return -EINVAL; if (change == KVM_MR_CREATE || change == KVM_MR_MOVE) { if ((new->base_gfn + new->npages - 1) > kvm_mmu_max_gfn()) return -EINVAL; return kvm_alloc_memslot_metadata(kvm, new); } if (change == KVM_MR_FLAGS_ONLY) memcpy(&new->arch, &old->arch, sizeof(old->arch)); else if (WARN_ON_ONCE(change != KVM_MR_DELETE)) return -EIO; return 0; } static void kvm_mmu_update_cpu_dirty_logging(struct kvm *kvm, bool enable) { int nr_slots; if (!kvm_x86_ops.cpu_dirty_log_size) return; nr_slots = atomic_read(&kvm->nr_memslots_dirty_logging); if ((enable && nr_slots == 1) || !nr_slots) kvm_make_all_cpus_request(kvm, KVM_REQ_UPDATE_CPU_DIRTY_LOGGING); } static void kvm_mmu_slot_apply_flags(struct kvm *kvm, struct kvm_memory_slot *old, const struct kvm_memory_slot *new, enum kvm_mr_change change) { u32 old_flags = old ? old->flags : 0; u32 new_flags = new ? new->flags : 0; bool log_dirty_pages = new_flags & KVM_MEM_LOG_DIRTY_PAGES; /* * Update CPU dirty logging if dirty logging is being toggled. This * applies to all operations. */ if ((old_flags ^ new_flags) & KVM_MEM_LOG_DIRTY_PAGES) kvm_mmu_update_cpu_dirty_logging(kvm, log_dirty_pages); /* * Nothing more to do for RO slots (which can't be dirtied and can't be * made writable) or CREATE/MOVE/DELETE of a slot. * * For a memslot with dirty logging disabled: * CREATE: No dirty mappings will already exist. * MOVE/DELETE: The old mappings will already have been cleaned up by * kvm_arch_flush_shadow_memslot() * * For a memslot with dirty logging enabled: * CREATE: No shadow pages exist, thus nothing to write-protect * and no dirty bits to clear. * MOVE/DELETE: The old mappings will already have been cleaned up by * kvm_arch_flush_shadow_memslot(). */ if ((change != KVM_MR_FLAGS_ONLY) || (new_flags & KVM_MEM_READONLY)) return; /* * READONLY and non-flags changes were filtered out above, and the only * other flag is LOG_DIRTY_PAGES, i.e. something is wrong if dirty * logging isn't being toggled on or off. */ if (WARN_ON_ONCE(!((old_flags ^ new_flags) & KVM_MEM_LOG_DIRTY_PAGES))) return; if (!log_dirty_pages) { /* * Dirty logging tracks sptes in 4k granularity, meaning that * large sptes have to be split. If live migration succeeds, * the guest in the source machine will be destroyed and large * sptes will be created in the destination. However, if the * guest continues to run in the source machine (for example if * live migration fails), small sptes will remain around and * cause bad performance. * * Scan sptes if dirty logging has been stopped, dropping those * which can be collapsed into a single large-page spte. Later * page faults will create the large-page sptes. */ kvm_mmu_zap_collapsible_sptes(kvm, new); } else { /* * Initially-all-set does not require write protecting any page, * because they're all assumed to be dirty. */ if (kvm_dirty_log_manual_protect_and_init_set(kvm)) return; if (READ_ONCE(eager_page_split)) kvm_mmu_slot_try_split_huge_pages(kvm, new, PG_LEVEL_4K); if (kvm_x86_ops.cpu_dirty_log_size) { kvm_mmu_slot_leaf_clear_dirty(kvm, new); kvm_mmu_slot_remove_write_access(kvm, new, PG_LEVEL_2M); } else { kvm_mmu_slot_remove_write_access(kvm, new, PG_LEVEL_4K); } /* * Unconditionally flush the TLBs after enabling dirty logging. * A flush is almost always going to be necessary (see below), * and unconditionally flushing allows the helpers to omit * the subtly complex checks when removing write access. * * Do the flush outside of mmu_lock to reduce the amount of * time mmu_lock is held. Flushing after dropping mmu_lock is * safe as KVM only needs to guarantee the slot is fully * write-protected before returning to userspace, i.e. before * userspace can consume the dirty status. * * Flushing outside of mmu_lock requires KVM to be careful when * making decisions based on writable status of an SPTE, e.g. a * !writable SPTE doesn't guarantee a CPU can't perform writes. * * Specifically, KVM also write-protects guest page tables to * monitor changes when using shadow paging, and must guarantee * no CPUs can write to those page before mmu_lock is dropped. * Because CPUs may have stale TLB entries at this point, a * !writable SPTE doesn't guarantee CPUs can't perform writes. * * KVM also allows making SPTES writable outside of mmu_lock, * e.g. to allow dirty logging without taking mmu_lock. * * To handle these scenarios, KVM uses a separate software-only * bit (MMU-writable) to track if a SPTE is !writable due to * a guest page table being write-protected (KVM clears the * MMU-writable flag when write-protecting for shadow paging). * * The use of MMU-writable is also the primary motivation for * the unconditional flush. Because KVM must guarantee that a * CPU doesn't contain stale, writable TLB entries for a * !MMU-writable SPTE, KVM must flush if it encounters any * MMU-writable SPTE regardless of whether the actual hardware * writable bit was set. I.e. KVM is almost guaranteed to need * to flush, while unconditionally flushing allows the "remove * write access" helpers to ignore MMU-writable entirely. * * See is_writable_pte() for more details (the case involving * access-tracked SPTEs is particularly relevant). */ kvm_flush_remote_tlbs_memslot(kvm, new); } } void kvm_arch_commit_memory_region(struct kvm *kvm, struct kvm_memory_slot *old, const struct kvm_memory_slot *new, enum kvm_mr_change change) { if (change == KVM_MR_DELETE) kvm_page_track_delete_slot(kvm, old); if (!kvm->arch.n_requested_mmu_pages && (change == KVM_MR_CREATE || change == KVM_MR_DELETE)) { unsigned long nr_mmu_pages; nr_mmu_pages = kvm->nr_memslot_pages / KVM_MEMSLOT_PAGES_TO_MMU_PAGES_RATIO; nr_mmu_pages = max(nr_mmu_pages, KVM_MIN_ALLOC_MMU_PAGES); kvm_mmu_change_mmu_pages(kvm, nr_mmu_pages); } kvm_mmu_slot_apply_flags(kvm, old, new, change); /* Free the arrays associated with the old memslot. */ if (change == KVM_MR_MOVE) kvm_arch_free_memslot(kvm, old); } static inline bool kvm_guest_apic_has_interrupt(struct kvm_vcpu *vcpu) { return (is_guest_mode(vcpu) && static_call(kvm_x86_guest_apic_has_interrupt)(vcpu)); } static inline bool kvm_vcpu_has_events(struct kvm_vcpu *vcpu) { if (!list_empty_careful(&vcpu->async_pf.done)) return true; if (kvm_apic_has_pending_init_or_sipi(vcpu) && kvm_apic_init_sipi_allowed(vcpu)) return true; if (vcpu->arch.pv.pv_unhalted) return true; if (kvm_is_exception_pending(vcpu)) return true; if (kvm_test_request(KVM_REQ_NMI, vcpu) || (vcpu->arch.nmi_pending && static_call(kvm_x86_nmi_allowed)(vcpu, false))) return true; #ifdef CONFIG_KVM_SMM if (kvm_test_request(KVM_REQ_SMI, vcpu) || (vcpu->arch.smi_pending && static_call(kvm_x86_smi_allowed)(vcpu, false))) return true; #endif if (kvm_test_request(KVM_REQ_PMI, vcpu)) return true; if (kvm_arch_interrupt_allowed(vcpu) && (kvm_cpu_has_interrupt(vcpu) || kvm_guest_apic_has_interrupt(vcpu))) return true; if (kvm_hv_has_stimer_pending(vcpu)) return true; if (is_guest_mode(vcpu) && kvm_x86_ops.nested_ops->has_events && kvm_x86_ops.nested_ops->has_events(vcpu)) return true; if (kvm_xen_has_pending_events(vcpu)) return true; return false; } int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu) { return kvm_vcpu_running(vcpu) || kvm_vcpu_has_events(vcpu); } bool kvm_arch_dy_has_pending_interrupt(struct kvm_vcpu *vcpu) { if (kvm_vcpu_apicv_active(vcpu) && static_call(kvm_x86_dy_apicv_has_pending_interrupt)(vcpu)) return true; return false; } bool kvm_arch_vcpu_preempted_in_kernel(struct kvm_vcpu *vcpu) { return vcpu->arch.preempted_in_kernel; } bool kvm_arch_dy_runnable(struct kvm_vcpu *vcpu) { if (READ_ONCE(vcpu->arch.pv.pv_unhalted)) return true; if (kvm_test_request(KVM_REQ_NMI, vcpu) || #ifdef CONFIG_KVM_SMM kvm_test_request(KVM_REQ_SMI, vcpu) || #endif kvm_test_request(KVM_REQ_EVENT, vcpu)) return true; return kvm_arch_dy_has_pending_interrupt(vcpu); } bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) { if (vcpu->arch.guest_state_protected) return true; return static_call(kvm_x86_get_cpl)(vcpu) == 0; } unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu) { return kvm_rip_read(vcpu); } int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu) { return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE; } int kvm_arch_interrupt_allowed(struct kvm_vcpu *vcpu) { return static_call(kvm_x86_interrupt_allowed)(vcpu, false); } unsigned long kvm_get_linear_rip(struct kvm_vcpu *vcpu) { /* Can't read the RIP when guest state is protected, just return 0 */ if (vcpu->arch.guest_state_protected) return 0; if (is_64_bit_mode(vcpu)) return kvm_rip_read(vcpu); return (u32)(get_segment_base(vcpu, VCPU_SREG_CS) + kvm_rip_read(vcpu)); } EXPORT_SYMBOL_GPL(kvm_get_linear_rip); bool kvm_is_linear_rip(struct kvm_vcpu *vcpu, unsigned long linear_rip) { return kvm_get_linear_rip(vcpu) == linear_rip; } EXPORT_SYMBOL_GPL(kvm_is_linear_rip); unsigned long kvm_get_rflags(struct kvm_vcpu *vcpu) { unsigned long rflags; rflags = static_call(kvm_x86_get_rflags)(vcpu); if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) rflags &= ~X86_EFLAGS_TF; return rflags; } EXPORT_SYMBOL_GPL(kvm_get_rflags); static void __kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags) { if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP && kvm_is_linear_rip(vcpu, vcpu->arch.singlestep_rip)) rflags |= X86_EFLAGS_TF; static_call(kvm_x86_set_rflags)(vcpu, rflags); } void kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags) { __kvm_set_rflags(vcpu, rflags); kvm_make_request(KVM_REQ_EVENT, vcpu); } EXPORT_SYMBOL_GPL(kvm_set_rflags); static inline u32 kvm_async_pf_hash_fn(gfn_t gfn) { BUILD_BUG_ON(!is_power_of_2(ASYNC_PF_PER_VCPU)); return hash_32(gfn & 0xffffffff, order_base_2(ASYNC_PF_PER_VCPU)); } static inline u32 kvm_async_pf_next_probe(u32 key) { return (key + 1) & (ASYNC_PF_PER_VCPU - 1); } static void kvm_add_async_pf_gfn(struct kvm_vcpu *vcpu, gfn_t gfn) { u32 key = kvm_async_pf_hash_fn(gfn); while (vcpu->arch.apf.gfns[key] != ~0) key = kvm_async_pf_next_probe(key); vcpu->arch.apf.gfns[key] = gfn; } static u32 kvm_async_pf_gfn_slot(struct kvm_vcpu *vcpu, gfn_t gfn) { int i; u32 key = kvm_async_pf_hash_fn(gfn); for (i = 0; i < ASYNC_PF_PER_VCPU && (vcpu->arch.apf.gfns[key] != gfn && vcpu->arch.apf.gfns[key] != ~0); i++) key = kvm_async_pf_next_probe(key); return key; } bool kvm_find_async_pf_gfn(struct kvm_vcpu *vcpu, gfn_t gfn) { return vcpu->arch.apf.gfns[kvm_async_pf_gfn_slot(vcpu, gfn)] == gfn; } static void kvm_del_async_pf_gfn(struct kvm_vcpu *vcpu, gfn_t gfn) { u32 i, j, k; i = j = kvm_async_pf_gfn_slot(vcpu, gfn); if (WARN_ON_ONCE(vcpu->arch.apf.gfns[i] != gfn)) return; while (true) { vcpu->arch.apf.gfns[i] = ~0; do { j = kvm_async_pf_next_probe(j); if (vcpu->arch.apf.gfns[j] == ~0) return; k = kvm_async_pf_hash_fn(vcpu->arch.apf.gfns[j]); /* * k lies cyclically in ]i,j] * | i.k.j | * |....j i.k.| or |.k..j i...| */ } while ((i <= j) ? (i < k && k <= j) : (i < k || k <= j)); vcpu->arch.apf.gfns[i] = vcpu->arch.apf.gfns[j]; i = j; } } static inline int apf_put_user_notpresent(struct kvm_vcpu *vcpu) { u32 reason = KVM_PV_REASON_PAGE_NOT_PRESENT; return kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.apf.data, &reason, sizeof(reason)); } static inline int apf_put_user_ready(struct kvm_vcpu *vcpu, u32 token) { unsigned int offset = offsetof(struct kvm_vcpu_pv_apf_data, token); return kvm_write_guest_offset_cached(vcpu->kvm, &vcpu->arch.apf.data, &token, offset, sizeof(token)); } static inline bool apf_pageready_slot_free(struct kvm_vcpu *vcpu) { unsigned int offset = offsetof(struct kvm_vcpu_pv_apf_data, token); u32 val; if (kvm_read_guest_offset_cached(vcpu->kvm, &vcpu->arch.apf.data, &val, offset, sizeof(val))) return false; return !val; } static bool kvm_can_deliver_async_pf(struct kvm_vcpu *vcpu) { if (!kvm_pv_async_pf_enabled(vcpu)) return false; if (vcpu->arch.apf.send_user_only && static_call(kvm_x86_get_cpl)(vcpu) == 0) return false; if (is_guest_mode(vcpu)) { /* * L1 needs to opt into the special #PF vmexits that are * used to deliver async page faults. */ return vcpu->arch.apf.delivery_as_pf_vmexit; } else { /* * Play it safe in case the guest temporarily disables paging. * The real mode IDT in particular is unlikely to have a #PF * exception setup. */ return is_paging(vcpu); } } bool kvm_can_do_async_pf(struct kvm_vcpu *vcpu) { if (unlikely(!lapic_in_kernel(vcpu) || kvm_event_needs_reinjection(vcpu) || kvm_is_exception_pending(vcpu))) return false; if (kvm_hlt_in_guest(vcpu->kvm) && !kvm_can_deliver_async_pf(vcpu)) return false; /* * If interrupts are off we cannot even use an artificial * halt state. */ return kvm_arch_interrupt_allowed(vcpu); } bool kvm_arch_async_page_not_present(struct kvm_vcpu *vcpu, struct kvm_async_pf *work) { struct x86_exception fault; trace_kvm_async_pf_not_present(work->arch.token, work->cr2_or_gpa); kvm_add_async_pf_gfn(vcpu, work->arch.gfn); if (kvm_can_deliver_async_pf(vcpu) && !apf_put_user_notpresent(vcpu)) { fault.vector = PF_VECTOR; fault.error_code_valid = true; fault.error_code = 0; fault.nested_page_fault = false; fault.address = work->arch.token; fault.async_page_fault = true; kvm_inject_page_fault(vcpu, &fault); return true; } else { /* * It is not possible to deliver a paravirtualized asynchronous * page fault, but putting the guest in an artificial halt state * can be beneficial nevertheless: if an interrupt arrives, we * can deliver it timely and perhaps the guest will schedule * another process. When the instruction that triggered a page * fault is retried, hopefully the page will be ready in the host. */ kvm_make_request(KVM_REQ_APF_HALT, vcpu); return false; } } void kvm_arch_async_page_present(struct kvm_vcpu *vcpu, struct kvm_async_pf *work) { struct kvm_lapic_irq irq = { .delivery_mode = APIC_DM_FIXED, .vector = vcpu->arch.apf.vec }; if (work->wakeup_all) work->arch.token = ~0; /* broadcast wakeup */ else kvm_del_async_pf_gfn(vcpu, work->arch.gfn); trace_kvm_async_pf_ready(work->arch.token, work->cr2_or_gpa); if ((work->wakeup_all || work->notpresent_injected) && kvm_pv_async_pf_enabled(vcpu) && !apf_put_user_ready(vcpu, work->arch.token)) { vcpu->arch.apf.pageready_pending = true; kvm_apic_set_irq(vcpu, &irq, NULL); } vcpu->arch.apf.halted = false; vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE; } void kvm_arch_async_page_present_queued(struct kvm_vcpu *vcpu) { kvm_make_request(KVM_REQ_APF_READY, vcpu); if (!vcpu->arch.apf.pageready_pending) kvm_vcpu_kick(vcpu); } bool kvm_arch_can_dequeue_async_page_present(struct kvm_vcpu *vcpu) { if (!kvm_pv_async_pf_enabled(vcpu)) return true; else return kvm_lapic_enabled(vcpu) && apf_pageready_slot_free(vcpu); } void kvm_arch_start_assignment(struct kvm *kvm) { if (atomic_inc_return(&kvm->arch.assigned_device_count) == 1) static_call_cond(kvm_x86_pi_start_assignment)(kvm); } EXPORT_SYMBOL_GPL(kvm_arch_start_assignment); void kvm_arch_end_assignment(struct kvm *kvm) { atomic_dec(&kvm->arch.assigned_device_count); } EXPORT_SYMBOL_GPL(kvm_arch_end_assignment); bool noinstr kvm_arch_has_assigned_device(struct kvm *kvm) { return raw_atomic_read(&kvm->arch.assigned_device_count); } EXPORT_SYMBOL_GPL(kvm_arch_has_assigned_device); static void kvm_noncoherent_dma_assignment_start_or_stop(struct kvm *kvm) { /* * Non-coherent DMA assignment and de-assignment will affect * whether KVM honors guest MTRRs and cause changes in memtypes * in TDP. * So, pass %true unconditionally to indicate non-coherent DMA was, * or will be involved, and that zapping SPTEs might be necessary. */ if (__kvm_mmu_honors_guest_mtrrs(true)) kvm_zap_gfn_range(kvm, gpa_to_gfn(0), gpa_to_gfn(~0ULL)); } void kvm_arch_register_noncoherent_dma(struct kvm *kvm) { if (atomic_inc_return(&kvm->arch.noncoherent_dma_count) == 1) kvm_noncoherent_dma_assignment_start_or_stop(kvm); } EXPORT_SYMBOL_GPL(kvm_arch_register_noncoherent_dma); void kvm_arch_unregister_noncoherent_dma(struct kvm *kvm) { if (!atomic_dec_return(&kvm->arch.noncoherent_dma_count)) kvm_noncoherent_dma_assignment_start_or_stop(kvm); } EXPORT_SYMBOL_GPL(kvm_arch_unregister_noncoherent_dma); bool kvm_arch_has_noncoherent_dma(struct kvm *kvm) { return atomic_read(&kvm->arch.noncoherent_dma_count); } EXPORT_SYMBOL_GPL(kvm_arch_has_noncoherent_dma); bool kvm_arch_has_irq_bypass(void) { return enable_apicv && irq_remapping_cap(IRQ_POSTING_CAP); } int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, struct irq_bypass_producer *prod) { struct kvm_kernel_irqfd *irqfd = container_of(cons, struct kvm_kernel_irqfd, consumer); int ret; irqfd->producer = prod; kvm_arch_start_assignment(irqfd->kvm); ret = static_call(kvm_x86_pi_update_irte)(irqfd->kvm, prod->irq, irqfd->gsi, 1); if (ret) kvm_arch_end_assignment(irqfd->kvm); return ret; } void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, struct irq_bypass_producer *prod) { int ret; struct kvm_kernel_irqfd *irqfd = container_of(cons, struct kvm_kernel_irqfd, consumer); WARN_ON(irqfd->producer != prod); irqfd->producer = NULL; /* * When producer of consumer is unregistered, we change back to * remapped mode, so we can re-use the current implementation * when the irq is masked/disabled or the consumer side (KVM * int this case doesn't want to receive the interrupts. */ ret = static_call(kvm_x86_pi_update_irte)(irqfd->kvm, prod->irq, irqfd->gsi, 0); if (ret) printk(KERN_INFO "irq bypass consumer (token %p) unregistration" " fails: %d\n", irqfd->consumer.token, ret); kvm_arch_end_assignment(irqfd->kvm); } int kvm_arch_update_irqfd_routing(struct kvm *kvm, unsigned int host_irq, uint32_t guest_irq, bool set) { return static_call(kvm_x86_pi_update_irte)(kvm, host_irq, guest_irq, set); } bool kvm_arch_irqfd_route_changed(struct kvm_kernel_irq_routing_entry *old, struct kvm_kernel_irq_routing_entry *new) { if (new->type != KVM_IRQ_ROUTING_MSI) return true; return !!memcmp(&old->msi, &new->msi, sizeof(new->msi)); } bool kvm_vector_hashing_enabled(void) { return vector_hashing; } bool kvm_arch_no_poll(struct kvm_vcpu *vcpu) { return (vcpu->arch.msr_kvm_poll_control & 1) == 0; } EXPORT_SYMBOL_GPL(kvm_arch_no_poll); int kvm_spec_ctrl_test_value(u64 value) { /* * test that setting IA32_SPEC_CTRL to given value * is allowed by the host processor */ u64 saved_value; unsigned long flags; int ret = 0; local_irq_save(flags); if (rdmsrl_safe(MSR_IA32_SPEC_CTRL, &saved_value)) ret = 1; else if (wrmsrl_safe(MSR_IA32_SPEC_CTRL, value)) ret = 1; else wrmsrl(MSR_IA32_SPEC_CTRL, saved_value); local_irq_restore(flags); return ret; } EXPORT_SYMBOL_GPL(kvm_spec_ctrl_test_value); void kvm_fixup_and_inject_pf_error(struct kvm_vcpu *vcpu, gva_t gva, u16 error_code) { struct kvm_mmu *mmu = vcpu->arch.walk_mmu; struct x86_exception fault; u64 access = error_code & (PFERR_WRITE_MASK | PFERR_FETCH_MASK | PFERR_USER_MASK); if (!(error_code & PFERR_PRESENT_MASK) || mmu->gva_to_gpa(vcpu, mmu, gva, access, &fault) != INVALID_GPA) { /* * If vcpu->arch.walk_mmu->gva_to_gpa succeeded, the page * tables probably do not match the TLB. Just proceed * with the error code that the processor gave. */ fault.vector = PF_VECTOR; fault.error_code_valid = true; fault.error_code = error_code; fault.nested_page_fault = false; fault.address = gva; fault.async_page_fault = false; } vcpu->arch.walk_mmu->inject_page_fault(vcpu, &fault); } EXPORT_SYMBOL_GPL(kvm_fixup_and_inject_pf_error); /* * Handles kvm_read/write_guest_virt*() result and either injects #PF or returns * KVM_EXIT_INTERNAL_ERROR for cases not currently handled by KVM. Return value * indicates whether exit to userspace is needed. */ int kvm_handle_memory_failure(struct kvm_vcpu *vcpu, int r, struct x86_exception *e) { if (r == X86EMUL_PROPAGATE_FAULT) { if (KVM_BUG_ON(!e, vcpu->kvm)) return -EIO; kvm_inject_emulated_page_fault(vcpu, e); return 1; } /* * In case kvm_read/write_guest_virt*() failed with X86EMUL_IO_NEEDED * while handling a VMX instruction KVM could've handled the request * correctly by exiting to userspace and performing I/O but there * doesn't seem to be a real use-case behind such requests, just return * KVM_EXIT_INTERNAL_ERROR for now. */ kvm_prepare_emulation_failure_exit(vcpu); return 0; } EXPORT_SYMBOL_GPL(kvm_handle_memory_failure); int kvm_handle_invpcid(struct kvm_vcpu *vcpu, unsigned long type, gva_t gva) { bool pcid_enabled; struct x86_exception e; struct { u64 pcid; u64 gla; } operand; int r; r = kvm_read_guest_virt(vcpu, gva, &operand, sizeof(operand), &e); if (r != X86EMUL_CONTINUE) return kvm_handle_memory_failure(vcpu, r, &e); if (operand.pcid >> 12 != 0) { kvm_inject_gp(vcpu, 0); return 1; } pcid_enabled = kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE); switch (type) { case INVPCID_TYPE_INDIV_ADDR: /* * LAM doesn't apply to addresses that are inputs to TLB * invalidation. */ if ((!pcid_enabled && (operand.pcid != 0)) || is_noncanonical_address(operand.gla, vcpu)) { kvm_inject_gp(vcpu, 0); return 1; } kvm_mmu_invpcid_gva(vcpu, operand.gla, operand.pcid); return kvm_skip_emulated_instruction(vcpu); case INVPCID_TYPE_SINGLE_CTXT: if (!pcid_enabled && (operand.pcid != 0)) { kvm_inject_gp(vcpu, 0); return 1; } kvm_invalidate_pcid(vcpu, operand.pcid); return kvm_skip_emulated_instruction(vcpu); case INVPCID_TYPE_ALL_NON_GLOBAL: /* * Currently, KVM doesn't mark global entries in the shadow * page tables, so a non-global flush just degenerates to a * global flush. If needed, we could optimize this later by * keeping track of global entries in shadow page tables. */ fallthrough; case INVPCID_TYPE_ALL_INCL_GLOBAL: kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu); return kvm_skip_emulated_instruction(vcpu); default: kvm_inject_gp(vcpu, 0); return 1; } } EXPORT_SYMBOL_GPL(kvm_handle_invpcid); static int complete_sev_es_emulated_mmio(struct kvm_vcpu *vcpu) { struct kvm_run *run = vcpu->run; struct kvm_mmio_fragment *frag; unsigned int len; BUG_ON(!vcpu->mmio_needed); /* Complete previous fragment */ frag = &vcpu->mmio_fragments[vcpu->mmio_cur_fragment]; len = min(8u, frag->len); if (!vcpu->mmio_is_write) memcpy(frag->data, run->mmio.data, len); if (frag->len <= 8) { /* Switch to the next fragment. */ frag++; vcpu->mmio_cur_fragment++; } else { /* Go forward to the next mmio piece. */ frag->data += len; frag->gpa += len; frag->len -= len; } if (vcpu->mmio_cur_fragment >= vcpu->mmio_nr_fragments) { vcpu->mmio_needed = 0; // VMG change, at this point, we're always done // RIP has already been advanced return 1; } // More MMIO is needed run->mmio.phys_addr = frag->gpa; run->mmio.len = min(8u, frag->len); run->mmio.is_write = vcpu->mmio_is_write; if (run->mmio.is_write) memcpy(run->mmio.data, frag->data, min(8u, frag->len)); run->exit_reason = KVM_EXIT_MMIO; vcpu->arch.complete_userspace_io = complete_sev_es_emulated_mmio; return 0; } int kvm_sev_es_mmio_write(struct kvm_vcpu *vcpu, gpa_t gpa, unsigned int bytes, void *data) { int handled; struct kvm_mmio_fragment *frag; if (!data) return -EINVAL; handled = write_emultor.read_write_mmio(vcpu, gpa, bytes, data); if (handled == bytes) return 1; bytes -= handled; gpa += handled; data += handled; /*TODO: Check if need to increment number of frags */ frag = vcpu->mmio_fragments; vcpu->mmio_nr_fragments = 1; frag->len = bytes; frag->gpa = gpa; frag->data = data; vcpu->mmio_needed = 1; vcpu->mmio_cur_fragment = 0; vcpu->run->mmio.phys_addr = gpa; vcpu->run->mmio.len = min(8u, frag->len); vcpu->run->mmio.is_write = 1; memcpy(vcpu->run->mmio.data, frag->data, min(8u, frag->len)); vcpu->run->exit_reason = KVM_EXIT_MMIO; vcpu->arch.complete_userspace_io = complete_sev_es_emulated_mmio; return 0; } EXPORT_SYMBOL_GPL(kvm_sev_es_mmio_write); int kvm_sev_es_mmio_read(struct kvm_vcpu *vcpu, gpa_t gpa, unsigned int bytes, void *data) { int handled; struct kvm_mmio_fragment *frag; if (!data) return -EINVAL; handled = read_emultor.read_write_mmio(vcpu, gpa, bytes, data); if (handled == bytes) return 1; bytes -= handled; gpa += handled; data += handled; /*TODO: Check if need to increment number of frags */ frag = vcpu->mmio_fragments; vcpu->mmio_nr_fragments = 1; frag->len = bytes; frag->gpa = gpa; frag->data = data; vcpu->mmio_needed = 1; vcpu->mmio_cur_fragment = 0; vcpu->run->mmio.phys_addr = gpa; vcpu->run->mmio.len = min(8u, frag->len); vcpu->run->mmio.is_write = 0; vcpu->run->exit_reason = KVM_EXIT_MMIO; vcpu->arch.complete_userspace_io = complete_sev_es_emulated_mmio; return 0; } EXPORT_SYMBOL_GPL(kvm_sev_es_mmio_read); static void advance_sev_es_emulated_pio(struct kvm_vcpu *vcpu, unsigned count, int size) { vcpu->arch.sev_pio_count -= count; vcpu->arch.sev_pio_data += count * size; } static int kvm_sev_es_outs(struct kvm_vcpu *vcpu, unsigned int size, unsigned int port); static int complete_sev_es_emulated_outs(struct kvm_vcpu *vcpu) { int size = vcpu->arch.pio.size; int port = vcpu->arch.pio.port; vcpu->arch.pio.count = 0; if (vcpu->arch.sev_pio_count) return kvm_sev_es_outs(vcpu, size, port); return 1; } static int kvm_sev_es_outs(struct kvm_vcpu *vcpu, unsigned int size, unsigned int port) { for (;;) { unsigned int count = min_t(unsigned int, PAGE_SIZE / size, vcpu->arch.sev_pio_count); int ret = emulator_pio_out(vcpu, size, port, vcpu->arch.sev_pio_data, count); /* memcpy done already by emulator_pio_out. */ advance_sev_es_emulated_pio(vcpu, count, size); if (!ret) break; /* Emulation done by the kernel. */ if (!vcpu->arch.sev_pio_count) return 1; } vcpu->arch.complete_userspace_io = complete_sev_es_emulated_outs; return 0; } static int kvm_sev_es_ins(struct kvm_vcpu *vcpu, unsigned int size, unsigned int port); static int complete_sev_es_emulated_ins(struct kvm_vcpu *vcpu) { unsigned count = vcpu->arch.pio.count; int size = vcpu->arch.pio.size; int port = vcpu->arch.pio.port; complete_emulator_pio_in(vcpu, vcpu->arch.sev_pio_data); advance_sev_es_emulated_pio(vcpu, count, size); if (vcpu->arch.sev_pio_count) return kvm_sev_es_ins(vcpu, size, port); return 1; } static int kvm_sev_es_ins(struct kvm_vcpu *vcpu, unsigned int size, unsigned int port) { for (;;) { unsigned int count = min_t(unsigned int, PAGE_SIZE / size, vcpu->arch.sev_pio_count); if (!emulator_pio_in(vcpu, size, port, vcpu->arch.sev_pio_data, count)) break; /* Emulation done by the kernel. */ advance_sev_es_emulated_pio(vcpu, count, size); if (!vcpu->arch.sev_pio_count) return 1; } vcpu->arch.complete_userspace_io = complete_sev_es_emulated_ins; return 0; } int kvm_sev_es_string_io(struct kvm_vcpu *vcpu, unsigned int size, unsigned int port, void *data, unsigned int count, int in) { vcpu->arch.sev_pio_data = data; vcpu->arch.sev_pio_count = count; return in ? kvm_sev_es_ins(vcpu, size, port) : kvm_sev_es_outs(vcpu, size, port); } EXPORT_SYMBOL_GPL(kvm_sev_es_string_io); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_entry); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_exit); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_fast_mmio); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_inj_virq); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_page_fault); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_msr); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_cr); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmenter); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmexit); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmexit_inject); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_intr_vmexit); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmenter_failed); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_invlpga); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_skinit); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_intercepts); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_write_tsc_offset); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_ple_window_update); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_pml_full); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_pi_irte_update); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_unaccelerated_access); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_incomplete_ipi); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_ga_log); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_kick_vcpu_slowpath); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_doorbell); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_apicv_accept_irq); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_enter); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_exit); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_msr_protocol_enter); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_msr_protocol_exit); static int __init kvm_x86_init(void) { kvm_mmu_x86_module_init(); mitigate_smt_rsb &= boot_cpu_has_bug(X86_BUG_SMT_RSB) && cpu_smt_possible(); return 0; } module_init(kvm_x86_init); static void __exit kvm_x86_exit(void) { WARN_ON_ONCE(static_branch_unlikely(&kvm_has_noapic_vcpu)); } module_exit(kvm_x86_exit);