From 703c335d06934401763863cf24fee61a13de055b Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Mon, 2 Mar 2020 15:57:03 -0800 Subject: [PATCH] KVM: x86/mmu: Configure max page level during hardware setup Configure the max page level during hardware setup to avoid a retpoline in the page fault handler. Drop ->get_lpage_level() as the page fault handler was the last user. No functional change intended. Reviewed-by: Vitaly Kuznetsov Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 3 +-- arch/x86/kvm/mmu/mmu.c | 20 ++++++++++++++++++-- arch/x86/kvm/svm.c | 9 +-------- arch/x86/kvm/vmx/vmx.c | 24 +++++++++++------------- 4 files changed, 31 insertions(+), 25 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index c9b721140f59..c817987c599e 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1155,7 +1155,6 @@ struct kvm_x86_ops { int (*set_identity_map_addr)(struct kvm *kvm, u64 ident_addr); int (*get_tdp_level)(struct kvm_vcpu *vcpu); u64 (*get_mt_mask)(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio); - int (*get_lpage_level)(void); void (*set_tdp_cr3)(struct kvm_vcpu *vcpu, unsigned long cr3); @@ -1510,7 +1509,7 @@ void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva); void kvm_mmu_invpcid_gva(struct kvm_vcpu *vcpu, gva_t gva, unsigned long pcid); void kvm_mmu_new_cr3(struct kvm_vcpu *vcpu, gpa_t new_cr3, bool skip_tlb_flush); -void kvm_configure_mmu(bool enable_tdp); +void kvm_configure_mmu(bool enable_tdp, int tdp_page_level); static inline gpa_t translate_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u32 access, struct x86_exception *exception) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 724bc8051117..554546948e87 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -87,6 +87,8 @@ __MODULE_PARM_TYPE(nx_huge_pages_recovery_ratio, "uint"); */ bool tdp_enabled = false; +static int max_page_level __read_mostly; + enum { AUDIT_PRE_PAGE_FAULT, AUDIT_POST_PAGE_FAULT, @@ -3282,7 +3284,7 @@ static int kvm_mmu_hugepage_adjust(struct kvm_vcpu *vcpu, gfn_t gfn, if (!slot) return PT_PAGE_TABLE_LEVEL; - max_level = min(max_level, kvm_x86_ops->get_lpage_level()); + max_level = min(max_level, max_page_level); for ( ; max_level > PT_PAGE_TABLE_LEVEL; max_level--) { linfo = lpage_info_slot(gfn, slot, max_level); if (!linfo->disallow_lpage) @@ -5559,9 +5561,23 @@ void kvm_mmu_invpcid_gva(struct kvm_vcpu *vcpu, gva_t gva, unsigned long pcid) } EXPORT_SYMBOL_GPL(kvm_mmu_invpcid_gva); -void kvm_configure_mmu(bool enable_tdp) +void kvm_configure_mmu(bool enable_tdp, int tdp_page_level) { tdp_enabled = enable_tdp; + + /* + * max_page_level reflects the capabilities of KVM's MMU irrespective + * of kernel support, e.g. KVM may be capable of using 1GB pages when + * the kernel is not. But, KVM never creates a page size greater than + * what is used by the kernel for any given HVA, i.e. the kernel's + * capabilities are ultimately consulted by kvm_mmu_hugepage_adjust(). + */ + if (tdp_enabled) + max_page_level = tdp_page_level; + else if (boot_cpu_has(X86_FEATURE_GBPAGES)) + max_page_level = PT_PDPE_LEVEL; + else + max_page_level = PT_DIRECTORY_LEVEL; } EXPORT_SYMBOL_GPL(kvm_configure_mmu); diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 422ee02afe8c..5e3261ec8c59 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1458,7 +1458,7 @@ static __init int svm_hardware_setup(void) if (npt_enabled && !npt) npt_enabled = false; - kvm_configure_mmu(npt_enabled); + kvm_configure_mmu(npt_enabled, PT_PDPE_LEVEL); pr_info("kvm: Nested Paging %sabled\n", npt_enabled ? "en" : "dis"); if (nrips) { @@ -6064,11 +6064,6 @@ static void svm_set_supported_cpuid(struct kvm_cpuid_entry2 *entry) } } -static int svm_get_lpage_level(void) -{ - return PT_PDPE_LEVEL; -} - static bool svm_has_wbinvd_exit(void) { return true; @@ -7426,8 +7421,6 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = { .get_exit_info = svm_get_exit_info, - .get_lpage_level = svm_get_lpage_level, - .cpuid_update = svm_cpuid_update, .set_supported_cpuid = svm_set_supported_cpuid, diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index b4ae305646fe..066c97ceebbf 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -6913,15 +6913,6 @@ exit: return (cache << VMX_EPT_MT_EPTE_SHIFT) | ipat; } -static int vmx_get_lpage_level(void) -{ - if (enable_ept && !cpu_has_vmx_ept_1g_page()) - return PT_DIRECTORY_LEVEL; - else - /* For shadow and EPT supported 1GB page */ - return PT_PDPE_LEVEL; -} - static void vmcs_set_secondary_exec_control(struct vcpu_vmx *vmx) { /* @@ -7653,7 +7644,7 @@ static __init int hardware_setup(void) { unsigned long host_bndcfgs; struct desc_ptr dt; - int r, i; + int r, i, ept_lpage_level; rdmsrl_safe(MSR_EFER, &host_efer); @@ -7746,7 +7737,16 @@ static __init int hardware_setup(void) if (enable_ept) vmx_enable_tdp(); - kvm_configure_mmu(enable_ept); + + if (!enable_ept) + ept_lpage_level = 0; + else if (cpu_has_vmx_ept_1g_page()) + ept_lpage_level = PT_PDPE_LEVEL; + else if (cpu_has_vmx_ept_2m_page()) + ept_lpage_level = PT_DIRECTORY_LEVEL; + else + ept_lpage_level = PT_PAGE_TABLE_LEVEL; + kvm_configure_mmu(enable_ept, ept_lpage_level); /* * Only enable PML when hardware supports PML feature, and both EPT @@ -7924,8 +7924,6 @@ static struct kvm_x86_ops vmx_x86_ops __ro_after_init = { .get_exit_info = vmx_get_exit_info, - .get_lpage_level = vmx_get_lpage_level, - .cpuid_update = vmx_cpuid_update, .set_supported_cpuid = vmx_set_supported_cpuid,