From 386bbf8992317f3106d45dbfdb4b577029e9091f Mon Sep 17 00:00:00 2001 From: Wei Wang Date: Tue, 7 Nov 2017 16:39:49 +0800 Subject: [PATCH] i386/kvm: MSR_IA32_SPEC_CTRL and MSR_IA32_PRED_CMD CPUID(EAX=0X7,ECX=0).EDX[26]/[27] indicates the support of MSR_IA32_SPEC_CTRL and MSR_IA32_PRED_CMD. Expose the CPUID to the guest. Also add the support of transferring the MSRs during live migration. Signed-off-by: Wei Wang [BR: BSC#1068032 CVE-2017-5715] Signed-off-by: Bruce Rogers --- target/i386/cpu.c | 3 ++- target/i386/cpu.h | 4 ++++ target/i386/kvm.c | 14 +++++++++++++- target/i386/machine.c | 20 ++++++++++++++++++++ 4 files changed, 39 insertions(+), 2 deletions(-) diff --git a/target/i386/cpu.c b/target/i386/cpu.c index 045d66191f..4a403b1e7b 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -2880,13 +2880,14 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count, case 7: /* Structured Extended Feature Flags Enumeration Leaf */ if (count == 0) { + host_cpuid(index, 0, eax, ebx, ecx, edx); *eax = 0; /* Maximum ECX value for sub-leaves */ *ebx = env->features[FEAT_7_0_EBX]; /* Feature flags */ *ecx = env->features[FEAT_7_0_ECX]; /* Feature flags */ if ((*ecx & CPUID_7_0_ECX_PKU) && env->cr[4] & CR4_PKE_MASK) { *ecx |= CPUID_7_0_ECX_OSPKE; } - *edx = env->features[FEAT_7_0_EDX]; /* Feature flags */ + *edx = env->features[FEAT_7_0_EDX] | *edx; } else { *eax = 0; *ebx = 0; diff --git a/target/i386/cpu.h b/target/i386/cpu.h index cbdd631e2e..d9ecf7a368 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -335,6 +335,7 @@ #define MSR_IA32_APICBASE_BASE (0xfffffU<<12) #define MSR_IA32_FEATURE_CONTROL 0x0000003a #define MSR_TSC_ADJUST 0x0000003b +#define MSR_IA32_SPEC_CTRL 0x00000048 #define MSR_IA32_TSCDEADLINE 0x6e0 #define FEATURE_CONTROL_LOCKED (1<<0) @@ -641,6 +642,8 @@ typedef uint32_t FeatureWordArray[FEATURE_WORDS]; #define CPUID_7_0_EDX_AVX512_4VNNIW (1U << 2) /* AVX512 Neural Network Instructions */ #define CPUID_7_0_EDX_AVX512_4FMAPS (1U << 3) /* AVX512 Multiply Accumulation Single Precision */ +#define CPUID_7_0_EDX_SPEC_CTRL (1U << 26) +#define CPUID_7_0_EDX_PRED_CMD (1U << 27) #define CPUID_XSAVE_XSAVEOPT (1U << 0) #define CPUID_XSAVE_XSAVEC (1U << 1) @@ -1183,6 +1186,7 @@ typedef struct CPUX86State { uint64_t xss; + uint64_t spec_ctrl; TPRAccess tpr_access_type; } CPUX86State; diff --git a/target/i386/kvm.c b/target/i386/kvm.c index b1e32e95d3..d0041e6285 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -76,6 +76,7 @@ static bool has_msr_star; static bool has_msr_hsave_pa; static bool has_msr_tsc_aux; static bool has_msr_tsc_adjust; +static bool has_msr_spec_ctrl; static bool has_msr_tsc_deadline; static bool has_msr_feature_control; static bool has_msr_misc_enable; @@ -1108,6 +1109,9 @@ static int kvm_get_supported_msrs(KVMState *s) case MSR_TSC_ADJUST: has_msr_tsc_adjust = true; break; + case MSR_IA32_SPEC_CTRL: + has_msr_spec_ctrl = true; + break; case MSR_IA32_TSCDEADLINE: has_msr_tsc_deadline = true; break; @@ -1626,6 +1630,9 @@ static int kvm_put_msrs(X86CPU *cpu, int level) if (has_msr_xss) { kvm_msr_entry_add(cpu, MSR_IA32_XSS, env->xss); } + if (has_msr_spec_ctrl) { + kvm_msr_entry_add(cpu, MSR_IA32_SPEC_CTRL, env->spec_ctrl); + } #ifdef TARGET_X86_64 if (lm_capable_kernel) { kvm_msr_entry_add(cpu, MSR_CSTAR, env->cstar); @@ -1998,7 +2005,9 @@ static int kvm_get_msrs(X86CPU *cpu) if (has_msr_xss) { kvm_msr_entry_add(cpu, MSR_IA32_XSS, 0); } - + if (has_msr_spec_ctrl) { + kvm_msr_entry_add(cpu, MSR_IA32_SPEC_CTRL, 0); + } if (!env->tsc_valid) { kvm_msr_entry_add(cpu, MSR_IA32_TSC, 0); @@ -2220,6 +2229,9 @@ static int kvm_get_msrs(X86CPU *cpu) case MSR_IA32_XSS: env->xss = msrs[i].data; break; + case MSR_IA32_SPEC_CTRL: + env->spec_ctrl = msrs[i].data; + break; default: if (msrs[i].index >= MSR_MC0_CTL && msrs[i].index < MSR_MC0_CTL + (env->mcg_cap & 0xff) * 4) { diff --git a/target/i386/machine.c b/target/i386/machine.c index df5ec359eb..d561a65153 100644 --- a/target/i386/machine.c +++ b/target/i386/machine.c @@ -759,6 +759,25 @@ static const VMStateDescription vmstate_xss = { } }; +static bool spec_ctrl_needed(void *opaque) +{ + X86CPU *cpu = opaque; + CPUX86State *env = &cpu->env; + + return env->spec_ctrl != 0; +} + +static const VMStateDescription vmstate_spec_ctrl = { + .name = "cpu/spec_ctrl", + .version_id = 1, + .minimum_version_id = 1, + .needed = spec_ctrl_needed, + .fields = (VMStateField[]) { + VMSTATE_UINT64(env.spec_ctrl, X86CPU), + VMSTATE_END_OF_LIST() + } +}; + #ifdef TARGET_X86_64 static bool pkru_needed(void *opaque) { @@ -932,6 +951,7 @@ VMStateDescription vmstate_x86_cpu = { &vmstate_msr_hyperv_stimer, &vmstate_avx512, &vmstate_xss, + &vmstate_spec_ctrl, &vmstate_tsc_khz, #ifdef TARGET_X86_64 &vmstate_pkru,