diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h index fc4a6c1235f0..c252efed49d9 100644 --- a/drivers/kvm/kvm.h +++ b/drivers/kvm/kvm.h @@ -288,6 +288,10 @@ struct kvm_vcpu { u64 apic_base; u64 ia32_misc_enable_msr; int nmsrs; + int save_nmsrs; +#ifdef CONFIG_X86_64 + int msr_offset_kernel_gs_base; +#endif struct vmx_msr_entry *guest_msrs; struct vmx_msr_entry *host_msrs; diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c index a05bfa085877..872ca0381fbe 100644 --- a/drivers/kvm/vmx.c +++ b/drivers/kvm/vmx.c @@ -85,19 +85,6 @@ static const u32 vmx_msr_index[] = { }; #define NR_VMX_MSR ARRAY_SIZE(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) { return (intr_info & (INTR_INFO_INTR_TYPE_MASK | INTR_INFO_VECTOR_MASK | @@ -118,13 +105,23 @@ 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; } @@ -307,10 +304,10 @@ 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 + vcpu->msr_offset_kernel_gs_base, 1); } #endif + load_msrs(vcpu->guest_msrs, vcpu->save_nmsrs); } static void vmx_load_host_state(struct kvm_vcpu *vcpu) @@ -337,12 +334,8 @@ 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->save_nmsrs); + load_msrs(vcpu->host_msrs, vcpu->save_nmsrs); } /* @@ -463,6 +456,20 @@ static void vmx_inject_gp(struct kvm_vcpu *vcpu, unsigned error_code) INTR_INFO_VALID_MASK); } +/* + * Swap MSR entry in host/guest MSR entry array. + */ +void move_msr_up(struct kvm_vcpu *vcpu, int from, int to) +{ + struct vmx_msr_entry tmp; + tmp = vcpu->guest_msrs[to]; + vcpu->guest_msrs[to] = vcpu->guest_msrs[from]; + vcpu->guest_msrs[from] = tmp; + tmp = vcpu->host_msrs[to]; + vcpu->host_msrs[to] = vcpu->host_msrs[from]; + vcpu->host_msrs[from] = tmp; +} + /* * Set up the vmcs to automatically save and restore system * msrs. Don't touch the 64-bit msrs if the guest is in legacy @@ -470,35 +477,54 @@ 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; + int index, save_nmsrs; - if (is_long_mode(vcpu)) - nr_skip = NR_BAD_MSRS; - else - nr_skip = NR_64BIT_MSRS; - nr_good_msrs = vcpu->nmsrs - nr_skip; - - /* - * 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; + save_nmsrs = 0; #ifdef CONFIG_X86_64 - if (is_long_mode(vcpu) && (vcpu->shadow_efer & EFER_SCE)) - ++nr_good_msrs; -#endif + if (is_long_mode(vcpu)) { + index = __find_msr_index(vcpu, MSR_SYSCALL_MASK); + if (index >= 0) + move_msr_up(vcpu, index, save_nmsrs++); + index = __find_msr_index(vcpu, MSR_LSTAR); + if (index >= 0) + move_msr_up(vcpu, index, save_nmsrs++); + index = __find_msr_index(vcpu, MSR_CSTAR); + if (index >= 0) + move_msr_up(vcpu, index, save_nmsrs++); + index = __find_msr_index(vcpu, MSR_KERNEL_GS_BASE); + if (index >= 0) + move_msr_up(vcpu, index, save_nmsrs++); + /* + * MSR_K6_STAR is only needed on long mode guests, and only + * if efer.sce is enabled. + */ + index = __find_msr_index(vcpu, MSR_K6_STAR); + if ((index >= 0) && (vcpu->shadow_efer & EFER_SCE)) + move_msr_up(vcpu, index, save_nmsrs++); } +#endif + vcpu->save_nmsrs = save_nmsrs; +#ifdef CONFIG_X86_64 + vcpu->msr_offset_kernel_gs_base = + __find_msr_index(vcpu, MSR_KERNEL_GS_BASE); +#endif + index = __find_msr_index(vcpu, MSR_EFER); + if (index >= 0) + save_nmsrs = 1; + else { + save_nmsrs = 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_nmsrs); + vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, save_nmsrs); + vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, save_nmsrs); } /* @@ -595,14 +621,6 @@ 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); @@ -620,6 +638,8 @@ 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->save_nmsrs); break; } return kvm_set_msr_common(vcpu, msr_index, data); @@ -1331,10 +1351,6 @@ static int vmx_vcpu_setup(struct kvm_vcpu *vcpu) vcpu->host_msrs[j].reserved = 0; vcpu->host_msrs[j].data = data; vcpu->guest_msrs[j] = vcpu->host_msrs[j]; -#ifdef CONFIG_X86_64 - if (index == MSR_KERNEL_GS_BASE) - msr_offset_kernel_gs_base = j; -#endif ++vcpu->nmsrs; }