diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h index 1bbafba..08dd73f 100644 --- a/drivers/kvm/kvm.h +++ b/drivers/kvm/kvm.h @@ -287,6 +287,7 @@ struct kvm_vcpu { u64 apic_base; u64 ia32_misc_enable_msr; int nmsrs; + int smsrs_bitmap; struct vmx_msr_entry *guest_msrs; struct vmx_msr_entry *host_msrs; diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c index 1288cff..44d8bc4 100644 --- a/drivers/kvm/kvm_main.c +++ b/drivers/kvm/kvm_main.c @@ -1596,21 +1596,27 @@ void kvm_resched(struct kvm_vcpu *vcpu) } EXPORT_SYMBOL_GPL(kvm_resched); -void load_msrs(struct vmx_msr_entry *e, int n) +void load_msrs(struct vmx_msr_entry *e, int bitmap) { - int i; + unsigned long nr; - for (i = 0; i < n; ++i) - wrmsrl(e[i].index, e[i].data); + while (bitmap) { + nr = __ffs(bitmap); + wrmsrl(e[nr].index, e[nr].data); + __clear_bit(nr,&bitmap); + } } EXPORT_SYMBOL_GPL(load_msrs); -void save_msrs(struct vmx_msr_entry *e, int n) +void save_msrs(struct vmx_msr_entry *e, int bitmap) { - int i; + unsigned long nr; - for (i = 0; i < n; ++i) - rdmsrl(e[i].index, e[i].data); + while (bitmap) { + nr = __ffs(bitmap); + rdmsrl(e[nr].index, e[nr].data); + __clear_bit(nr,&bitmap); + } } EXPORT_SYMBOL_GPL(save_msrs); diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c index 804a623..0c69fe4 100644 --- a/drivers/kvm/vmx.c +++ b/drivers/kvm/vmx.c @@ -86,15 +86,6 @@ static const u32 vmx_msr_index[] = { #ifdef CONFIG_X86_64 static unsigned msr_offset_kernel_gs_base; -#define NR_64BIT_MSRS 4 -/* - * avoid save/load MSR_SYSCALL_MASK and MSR_LSTAR by std vt - * mechanism (cpu bug AA24) - */ -#define NR_BAD_MSRS 2 -#else -#define NR_64BIT_MSRS 0 -#define NR_BAD_MSRS 0 #endif static inline int is_page_fault(u32 intr_info) @@ -117,13 +108,23 @@ static inline int is_external_interrupt(u32 intr_info) == (INTR_TYPE_EXT_INTR | INTR_INFO_VALID_MASK); } -static struct vmx_msr_entry *find_msr_entry(struct kvm_vcpu *vcpu, u32 msr) +static int __find_msr_index(struct kvm_vcpu *vcpu, u32 msr) { int i; for (i = 0; i < vcpu->nmsrs; ++i) if (vcpu->guest_msrs[i].index == msr) - return &vcpu->guest_msrs[i]; + return i; + return -1; +} + +static struct vmx_msr_entry *find_msr_entry(struct kvm_vcpu *vcpu, u32 msr) +{ + int i; + + i = __find_msr_index(vcpu, msr); + if (i >= 0) + return &vcpu->guest_msrs[i]; return NULL; } @@ -306,10 +307,10 @@ static void vmx_save_host_state(struct kvm_vcpu *vcpu) #ifdef CONFIG_X86_64 if (is_long_mode(vcpu)) { - save_msrs(vcpu->host_msrs + msr_offset_kernel_gs_base, 1); - load_msrs(vcpu->guest_msrs, NR_BAD_MSRS); + save_msrs(vcpu->host_msrs, 1 << msr_offset_kernel_gs_base); } #endif + load_msrs(vcpu->guest_msrs, vcpu->smsrs_bitmap); } static void vmx_load_host_state(struct kvm_vcpu *vcpu) @@ -336,12 +337,8 @@ static void vmx_load_host_state(struct kvm_vcpu *vcpu) reload_tss(); } -#ifdef CONFIG_X86_64 - if (is_long_mode(vcpu)) { - save_msrs(vcpu->guest_msrs, NR_BAD_MSRS); - load_msrs(vcpu->host_msrs, NR_BAD_MSRS); - } -#endif + save_msrs(vcpu->guest_msrs, vcpu->smsrs_bitmap); + load_msrs(vcpu->host_msrs, vcpu->smsrs_bitmap); } /* @@ -469,35 +466,51 @@ static void vmx_inject_gp(struct kvm_vcpu *vcpu, unsigned error_code) */ static void setup_msrs(struct kvm_vcpu *vcpu) { - int nr_skip, nr_good_msrs; - - if (is_long_mode(vcpu)) - nr_skip = NR_BAD_MSRS; - else - nr_skip = NR_64BIT_MSRS; - nr_good_msrs = vcpu->nmsrs - nr_skip; + int index,save_msrs; - /* - * MSR_K6_STAR is only needed on long mode guests, and only - * if efer.sce is enabled. - */ - if (find_msr_entry(vcpu, MSR_K6_STAR)) { - --nr_good_msrs; -#ifdef CONFIG_X86_64 - if (is_long_mode(vcpu) && (vcpu->shadow_efer & EFER_SCE)) - ++nr_good_msrs; + vcpu->smsrs_bitmap = 0; + if (is_long_mode(vcpu)) { + if ((index=__find_msr_index(vcpu, MSR_SYSCALL_MASK)) >= 0) { + set_bit(index, &vcpu->smsrs_bitmap); + } + if ((index=__find_msr_index(vcpu, MSR_LSTAR)) >= 0) { + set_bit(index, &vcpu->smsrs_bitmap); + } + if ((index=__find_msr_index(vcpu, MSR_CSTAR)) >= 0) { + set_bit(index, &vcpu->smsrs_bitmap); + } + if ((index=__find_msr_index(vcpu, MSR_KERNEL_GS_BASE)) >= 0) { + set_bit(index, &vcpu->smsrs_bitmap); + } + /* + * MSR_K6_STAR is only needed on long mode guests, and only + * if efer.sce is enabled. + */ + if ((index=__find_msr_index(vcpu, MSR_K6_STAR)) >= 0 +#ifdef X86_64 + && (vcpu->shadow_efer & EFER_SCE) #endif + ) { + set_bit(index, &vcpu->smsrs_bitmap); + } } + if ((index = __find_msr_index(vcpu, MSR_EFER)) >= 0) { + save_msrs = 1; + } + else { + save_msrs = 0; + index = 0; + } vmcs_writel(VM_ENTRY_MSR_LOAD_ADDR, - virt_to_phys(vcpu->guest_msrs + nr_skip)); + virt_to_phys(vcpu->guest_msrs + index)); vmcs_writel(VM_EXIT_MSR_STORE_ADDR, - virt_to_phys(vcpu->guest_msrs + nr_skip)); + virt_to_phys(vcpu->guest_msrs + index)); vmcs_writel(VM_EXIT_MSR_LOAD_ADDR, - virt_to_phys(vcpu->host_msrs + nr_skip)); - vmcs_write32(VM_EXIT_MSR_STORE_COUNT, nr_good_msrs); /* 22.2.2 */ - vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, nr_good_msrs); /* 22.2.2 */ - vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, nr_good_msrs); /* 22.2.2 */ + virt_to_phys(vcpu->host_msrs + index)); + vmcs_write32(VM_EXIT_MSR_STORE_COUNT, save_msrs); + vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, save_msrs); + vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, save_msrs); } /* @@ -594,14 +607,6 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data) case MSR_GS_BASE: vmcs_writel(GUEST_GS_BASE, data); break; - case MSR_LSTAR: - case MSR_SYSCALL_MASK: - msr = find_msr_entry(vcpu, msr_index); - if (msr) - msr->data = data; - if (vcpu->vmx_host_state.loaded) - load_msrs(vcpu->guest_msrs, NR_BAD_MSRS); - break; #endif case MSR_IA32_SYSENTER_CS: vmcs_write32(GUEST_SYSENTER_CS, data); @@ -619,6 +624,9 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data) msr = find_msr_entry(vcpu, msr_index); if (msr) { msr->data = data; + if (vcpu->vmx_host_state.loaded) + load_msrs(vcpu->guest_msrs, + vcpu->smsrs_bitmap); break; } return kvm_set_msr_common(vcpu, msr_index, data);