diff options
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 6 | ||||
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 2 | ||||
| -rw-r--r-- | arch/x86/kvm/cpuid.h | 8 | ||||
| -rw-r--r-- | arch/x86/kvm/svm.c | 59 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 20 |
5 files changed, 94 insertions, 1 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 52d6640a5ca..bd69c93da8f 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -478,6 +478,12 @@ struct kvm_vcpu_arch { u32 id; bool send_user_only; } apf; + + /* OSVW MSRs (AMD only) */ + struct { + u64 length; + u64 status; + } osvw; }; struct kvm_arch { diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 89b02bfaaca..9fed5bedaad 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -236,7 +236,7 @@ static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, const u32 kvm_supported_word6_x86_features = F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ | F(CR8_LEGACY) | F(ABM) | F(SSE4A) | F(MISALIGNSSE) | - F(3DNOWPREFETCH) | 0 /* OSVW */ | 0 /* IBS */ | F(XOP) | + F(3DNOWPREFETCH) | F(OSVW) | 0 /* IBS */ | F(XOP) | 0 /* SKINIT, WDT, LWP */ | F(FMA4) | F(TBM); /* cpuid 0xC0000001.edx */ diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h index 5b97e1797a6..26d1fb437eb 100644 --- a/arch/x86/kvm/cpuid.h +++ b/arch/x86/kvm/cpuid.h @@ -43,4 +43,12 @@ static inline bool guest_cpuid_has_fsgsbase(struct kvm_vcpu *vcpu) return best && (best->ebx & bit(X86_FEATURE_FSGSBASE)); } +static inline bool guest_cpuid_has_osvw(struct kvm_vcpu *vcpu) +{ + struct kvm_cpuid_entry2 *best; + + best = kvm_find_cpuid_entry(vcpu, 0x80000001, 0); + return best && (best->ecx & bit(X86_FEATURE_OSVW)); +} + #endif diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 5fa553babe5..fce3ba0f207 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -110,6 +110,12 @@ struct nested_state { #define MSRPM_OFFSETS 16 static u32 msrpm_offsets[MSRPM_OFFSETS] __read_mostly; +/* + * Set osvw_len to higher value when updated Revision Guides + * are published and we know what the new status bits are + */ +static uint64_t osvw_len = 4, osvw_status; + struct vcpu_svm { struct kvm_vcpu vcpu; struct vmcb *vmcb; @@ -556,6 +562,27 @@ static void svm_init_erratum_383(void) erratum_383_found = true; } +static void svm_init_osvw(struct kvm_vcpu *vcpu) +{ + /* + * Guests should see errata 400 and 415 as fixed (assuming that + * HLT and IO instructions are intercepted). + */ + vcpu->arch.osvw.length = (osvw_len >= 3) ? (osvw_len) : 3; + vcpu->arch.osvw.status = osvw_status & ~(6ULL); + + /* + * By increasing VCPU's osvw.length to 3 we are telling the guest that + * all osvw.status bits inside that length, including bit 0 (which is + * reserved for erratum 298), are valid. However, if host processor's + * osvw_len is 0 then osvw_status[0] carries no information. We need to + * be conservative here and therefore we tell the guest that erratum 298 + * is present (because we really don't know). + */ + if (osvw_len == 0 && boot_cpu_data.x86 == 0x10) + vcpu->arch.osvw.status |= 1; +} + static int has_svm(void) { const char *msg; @@ -620,6 +647,36 @@ static int svm_hardware_enable(void *garbage) __get_cpu_var(current_tsc_ratio) = TSC_RATIO_DEFAULT; } + + /* + * Get OSVW bits. + * + * Note that it is possible to have a system with mixed processor + * revisions and therefore different OSVW bits. If bits are not the same + * on different processors then choose the worst case (i.e. if erratum + * is present on one processor and not on another then assume that the + * erratum is present everywhere). + */ + if (cpu_has(&boot_cpu_data, X86_FEATURE_OSVW)) { + uint64_t len, status = 0; + int err; + + len = native_read_msr_safe(MSR_AMD64_OSVW_ID_LENGTH, &err); + if (!err) + status = native_read_msr_safe(MSR_AMD64_OSVW_STATUS, + &err); + + if (err) + osvw_status = osvw_len = 0; + else { + if (len < osvw_len) + osvw_len = len; + osvw_status |= status; + osvw_status &= (1ULL << osvw_len) - 1; + } + } else + osvw_status = osvw_len = 0; + svm_init_erratum_383(); return 0; @@ -1186,6 +1243,8 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id) if (kvm_vcpu_is_bsp(&svm->vcpu)) svm->vcpu.arch.apic_base |= MSR_IA32_APICBASE_BSP; + svm_init_osvw(&svm->vcpu); + return &svm->vcpu; free_page4: diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index a3ce196d21f..2bd77a3a41e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1675,6 +1675,16 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data) */ pr_unimpl(vcpu, "ignored wrmsr: 0x%x data %llx\n", msr, data); break; + case MSR_AMD64_OSVW_ID_LENGTH: + if (!guest_cpuid_has_osvw(vcpu)) + return 1; + vcpu->arch.osvw.length = data; + break; + case MSR_AMD64_OSVW_STATUS: + if (!guest_cpuid_has_osvw(vcpu)) + return 1; + vcpu->arch.osvw.status = data; + break; default: if (msr && (msr == vcpu->kvm->arch.xen_hvm_config.msr)) return xen_hvm_config(vcpu, data); @@ -1959,6 +1969,16 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata) */ data = 0xbe702111; break; + case MSR_AMD64_OSVW_ID_LENGTH: + if (!guest_cpuid_has_osvw(vcpu)) + return 1; + data = vcpu->arch.osvw.length; + break; + case MSR_AMD64_OSVW_STATUS: + if (!guest_cpuid_has_osvw(vcpu)) + return 1; + data = vcpu->arch.osvw.status; + break; default: if (kvm_pmu_msr(vcpu, msr)) return kvm_pmu_get_msr(vcpu, msr, pdata); |