From b8e6f8ae511d88732247aa2af26bfd1bef21b2f4 Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Tue, 13 Mar 2012 19:59:39 +0100 Subject: [PATCH 1/8] KVM: PPC: Book3S: Compile fix for ppc32 in HIOR access code MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We were failing to compile on book3s_32 with the following errors: arch/powerpc/kvm/book3s_pr.c:883:45: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast] arch/powerpc/kvm/book3s_pr.c:898:79: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast] Fix this by explicity casting the u64 to long before we use it as a pointer. Also, on PPC32 we can not use get_user/put_user for 64bit wide variables, as there is no single instruction that could load or store variables that big. So instead, we have to use copy_from/to_user which works everywhere. Reported-by: Jörg Sommer Signed-off-by: Alexander Graf Signed-off-by: Paul Mackerras --- arch/powerpc/kvm/book3s_pr.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index 642d88574b07..a657c44b7fbc 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -881,7 +881,8 @@ int kvm_vcpu_ioctl_get_one_reg(struct kvm_vcpu *vcpu, struct kvm_one_reg *reg) switch (reg->id) { case KVM_REG_PPC_HIOR: - r = put_user(to_book3s(vcpu)->hior, (u64 __user *)reg->addr); + r = copy_to_user((u64 __user *)(long)reg->addr, + &to_book3s(vcpu)->hior, sizeof(u64)); break; default: break; @@ -896,7 +897,8 @@ int kvm_vcpu_ioctl_set_one_reg(struct kvm_vcpu *vcpu, struct kvm_one_reg *reg) switch (reg->id) { case KVM_REG_PPC_HIOR: - r = get_user(to_book3s(vcpu)->hior, (u64 __user *)reg->addr); + r = copy_from_user(&to_book3s(vcpu)->hior, + (u64 __user *)(long)reg->addr, sizeof(u64)); if (!r) to_book3s(vcpu)->hior_explicit = true; break; From b4e51229d8a1e499fe65153766437152cca42053 Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Fri, 3 Feb 2012 00:45:02 +0000 Subject: [PATCH 2/8] KVM: PPC: Book3S HV: Fix kvm_alloc_linear in case where no linears exist In kvm_alloc_linear we were using and deferencing ri after the list_for_each_entry had come to the end of the list. In that situation, ri is not really defined and probably points to the list head. This will happen every time if the free_linears list is empty, for instance. This led to a NULL pointer dereference crash in memset on POWER7 while trying to allocate an HPT in the case where no HPTs were preallocated. This fixes it by using a separate variable for the return value from the loop iterator. Signed-off-by: Paul Mackerras Signed-off-by: Alexander Graf Signed-off-by: Paul Mackerras --- arch/powerpc/kvm/book3s_hv_builtin.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c index bed1279aa6a8..e1b60f56f2a1 100644 --- a/arch/powerpc/kvm/book3s_hv_builtin.c +++ b/arch/powerpc/kvm/book3s_hv_builtin.c @@ -173,9 +173,9 @@ static void __init kvm_linear_init_one(ulong size, int count, int type) static struct kvmppc_linear_info *kvm_alloc_linear(int type) { - struct kvmppc_linear_info *ri; + struct kvmppc_linear_info *ri, *ret; - ri = NULL; + ret = NULL; spin_lock(&linear_lock); list_for_each_entry(ri, &free_linears, list) { if (ri->type != type) @@ -183,11 +183,12 @@ static struct kvmppc_linear_info *kvm_alloc_linear(int type) list_del(&ri->list); atomic_inc(&ri->use_count); + memset(ri->base_virt, 0, ri->npages << PAGE_SHIFT); + ret = ri; break; } spin_unlock(&linear_lock); - memset(ri->base_virt, 0, ri->npages << PAGE_SHIFT); - return ri; + return ret; } static void kvm_release_linear(struct kvmppc_linear_info *ri) From a5ddea0e78e76aa8d6354b9b0e51e652e21b8137 Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Fri, 3 Feb 2012 00:53:21 +0000 Subject: [PATCH 3/8] KVM: PPC: Book3S HV: Save and restore CR in __kvmppc_vcore_entry The ABI specifies that CR fields CR2--CR4 are nonvolatile across function calls. Currently __kvmppc_vcore_entry doesn't save and restore the CR, leading to CR2--CR4 getting corrupted with guest values, possibly leading to incorrect behaviour in its caller. This adds instructions to save and restore CR at the points where we save and restore the nonvolatile GPRs. Signed-off-by: Paul Mackerras Signed-off-by: Alexander Graf Signed-off-by: Paul Mackerras --- arch/powerpc/kvm/book3s_hv_interrupts.S | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv_interrupts.S b/arch/powerpc/kvm/book3s_hv_interrupts.S index 3f7b674dd4bf..d3fb4df02c41 100644 --- a/arch/powerpc/kvm/book3s_hv_interrupts.S +++ b/arch/powerpc/kvm/book3s_hv_interrupts.S @@ -46,8 +46,10 @@ _GLOBAL(__kvmppc_vcore_entry) /* Save host state to the stack */ stdu r1, -SWITCH_FRAME_SIZE(r1) - /* Save non-volatile registers (r14 - r31) */ + /* Save non-volatile registers (r14 - r31) and CR */ SAVE_NVGPRS(r1) + mfcr r3 + std r3, _CCR(r1) /* Save host DSCR */ BEGIN_FTR_SECTION @@ -157,8 +159,10 @@ kvmppc_handler_highmem: * R13 = PACA */ - /* Restore non-volatile host registers (r14 - r31) */ + /* Restore non-volatile host registers (r14 - r31) and CR */ REST_NVGPRS(r1) + ld r4, _CCR(r1) + mtcr r4 addi r1, r1, SWITCH_FRAME_SIZE ld r0, PPC_LR_STKOFF(r1) From e1f8acf8380abfd52aefbfa524e74af5ce0c8492 Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Mon, 5 Mar 2012 16:00:28 +0100 Subject: [PATCH 4/8] KVM: PPC: Save/Restore CR over vcpu_run On PPC, CR2-CR4 are nonvolatile, thus have to be saved across function calls. We didn't respect that for any architecture until Paul spotted it in his patch for Book3S-HV. This patch saves/restores CR for all KVM capable PPC hosts. Signed-off-by: Alexander Graf Signed-off-by: Paul Mackerras --- arch/powerpc/kvm/book3s_interrupts.S | 7 +++++++ arch/powerpc/kvm/booke_interrupts.S | 7 ++++++- 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kvm/book3s_interrupts.S b/arch/powerpc/kvm/book3s_interrupts.S index 0a8515a5c042..3e35383bdb21 100644 --- a/arch/powerpc/kvm/book3s_interrupts.S +++ b/arch/powerpc/kvm/book3s_interrupts.S @@ -84,6 +84,10 @@ kvm_start_entry: /* Save non-volatile registers (r14 - r31) */ SAVE_NVGPRS(r1) + /* Save CR */ + mfcr r14 + stw r14, _CCR(r1) + /* Save LR */ PPC_STL r0, _LINK(r1) @@ -165,6 +169,9 @@ kvm_exit_loop: PPC_LL r4, _LINK(r1) mtlr r4 + lwz r14, _CCR(r1) + mtcr r14 + /* Restore non-volatile host registers (r14 - r31) */ REST_NVGPRS(r1) diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S index 10d8ef602e5c..c8c4b878795a 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -34,7 +34,8 @@ /* r2 is special: it holds 'current', and it made nonvolatile in the * kernel with the -ffixed-r2 gcc option. */ #define HOST_R2 12 -#define HOST_NV_GPRS 16 +#define HOST_CR 16 +#define HOST_NV_GPRS 20 #define HOST_NV_GPR(n) (HOST_NV_GPRS + ((n - 14) * 4)) #define HOST_MIN_STACK_SIZE (HOST_NV_GPR(31) + 4) #define HOST_STACK_SIZE (((HOST_MIN_STACK_SIZE + 15) / 16) * 16) /* Align. */ @@ -296,8 +297,10 @@ heavyweight_exit: /* Return to kvm_vcpu_run(). */ lwz r4, HOST_STACK_LR(r1) + lwz r5, HOST_CR(r1) addi r1, r1, HOST_STACK_SIZE mtlr r4 + mtcr r5 /* r3 still contains the return code from kvmppc_handle_exit(). */ blr @@ -314,6 +317,8 @@ _GLOBAL(__kvmppc_vcpu_run) stw r3, HOST_RUN(r1) mflr r3 stw r3, HOST_STACK_LR(r1) + mfcr r5 + stw r5, HOST_CR(r1) /* Save host non-volatile register state to stack. */ stw r14, HOST_NV_GPR(r14)(r1) From 592f5d87b3feee9d60411f19d583038c0c7670ad Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Tue, 13 Mar 2012 23:31:02 +0100 Subject: [PATCH 5/8] KVM: PPC: Book3S: PR: Fix preemption We were leaking preemption counters. Fix the code to always toggle between preempt and non-preempt properly. Signed-off-by: Alexander Graf Signed-off-by: Paul Mackerras --- arch/powerpc/kvm/book3s_pr.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index a657c44b7fbc..7759053d391b 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -777,6 +777,7 @@ program_interrupt: } } + preempt_disable(); if (!(r & RESUME_HOST)) { /* To avoid clobbering exit_reason, only check for signals if * we aren't already exiting to userspace for some other @@ -798,8 +799,6 @@ program_interrupt: run->exit_reason = KVM_EXIT_INTR; r = -EINTR; } else { - preempt_disable(); - /* In case an interrupt came in that was triggered * from userspace (like DEC), we need to check what * to inject now! */ From fea5295324ce7ce6ccfe0909cc6740a2d34aa5a3 Mon Sep 17 00:00:00 2001 From: Sasikantha babu Date: Wed, 21 Mar 2012 18:49:00 +0530 Subject: [PATCH 6/8] KVM: PMU: Fix integer constant is too large warning in kvm_pmu_set_msr() Signed-off-by: Sasikantha babu Signed-off-by: Avi Kivity --- arch/x86/kvm/pmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c index a73f0c104813..173df38dbda5 100644 --- a/arch/x86/kvm/pmu.c +++ b/arch/x86/kvm/pmu.c @@ -369,7 +369,7 @@ int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data) case MSR_CORE_PERF_FIXED_CTR_CTRL: if (pmu->fixed_ctr_ctrl == data) return 0; - if (!(data & 0xfffffffffffff444)) { + if (!(data & 0xfffffffffffff444ull)) { reprogram_fixed_counters(pmu, data); return 0; } From 7a4f5ad051e02139a9f1c0f7f4b1acb88915852b Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti Date: Tue, 27 Mar 2012 19:47:26 -0300 Subject: [PATCH 7/8] KVM: VMX: vmx_set_cr0 expects kvm->srcu locked vmx_set_cr0 is called from vcpu run context, therefore it expects kvm->srcu to be held (for setting up the real-mode TSS). Signed-off-by: Marcelo Tosatti Signed-off-by: Avi Kivity --- arch/x86/kvm/vmx.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 280751c84724..ad85adfef843 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3906,7 +3906,9 @@ static int vmx_vcpu_reset(struct kvm_vcpu *vcpu) vmcs_write16(VIRTUAL_PROCESSOR_ID, vmx->vpid); vmx->vcpu.arch.cr0 = X86_CR0_NW | X86_CR0_CD | X86_CR0_ET; + vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); vmx_set_cr0(&vmx->vcpu, kvm_read_cr0(vcpu)); /* enter rmode */ + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); vmx_set_cr4(&vmx->vcpu, 0); vmx_set_efer(&vmx->vcpu, 0); vmx_fpu_activate(&vmx->vcpu); From e08759215b7dcb7111e94f0f96918dd98e86ca6b Mon Sep 17 00:00:00 2001 From: Gleb Natapov Date: Wed, 4 Apr 2012 15:30:33 +0300 Subject: [PATCH 8/8] KVM: Resolve RCU vs. async page fault problem "Page ready" async PF can kick vcpu out of idle state much like IRQ. We need to tell RCU about this. Reported-by: Sasha Levin Signed-off-by: Gleb Natapov Reviewed-by: Paul E. McKenney Signed-off-by: Avi Kivity --- arch/x86/kernel/kvm.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 694d801bf606..b8ba6e4a27e4 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -38,6 +38,7 @@ #include #include #include +#include static int kvmapf = 1; @@ -253,7 +254,10 @@ do_async_page_fault(struct pt_regs *regs, unsigned long error_code) kvm_async_pf_task_wait((u32)read_cr2()); break; case KVM_PV_REASON_PAGE_READY: + rcu_irq_enter(); + exit_idle(); kvm_async_pf_task_wake((u32)read_cr2()); + rcu_irq_exit(); break; } }