--- a/target/i386/cpu.c +++ a/target/i386/cpu.c @@ -805,7 +805,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = { NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, "spec-ctrl", NULL, - NULL, NULL, NULL, NULL, + NULL, NULL, NULL, "ssbd", }, .cpuid_eax = 7, .cpuid_needs_ecx = true, .cpuid_ecx = 0, @@ -836,7 +836,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = { "ibpb", NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, - NULL, NULL, NULL, NULL, + NULL, "virt-ssbd", NULL, NULL, NULL, NULL, NULL, NULL, }, .cpuid_eax = 0x80000008, --- a/target/i386/cpu.h +++ a/target/i386/cpu.h @@ -351,6 +351,7 @@ typedef enum X86Seg { #define MSR_IA32_FEATURE_CONTROL 0x0000003a #define MSR_TSC_ADJUST 0x0000003b #define MSR_IA32_SPEC_CTRL 0x48 +#define MSR_VIRT_SSBD 0xc001011f #define MSR_IA32_TSCDEADLINE 0x6e0 #define FEATURE_CONTROL_LOCKED (1<<0) @@ -685,6 +686,7 @@ 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) /* Speculation Control */ +#define CPUID_7_0_EDX_SPEC_CTRL_SSBD (1U << 31) /* Speculative Store Bypass Disable */ #define KVM_HINTS_DEDICATED (1U << 0) @@ -1209,6 +1211,7 @@ typedef struct CPUX86State { uint32_t pkru; uint64_t spec_ctrl; + uint64_t virt_ssbd; /* End of state preserved by INIT (dummy marker). */ struct {} end_init_save; --- a/target/i386/kvm.c +++ a/target/i386/kvm.c @@ -93,6 +93,7 @@ static bool has_msr_hv_frequencies; static bool has_msr_hv_reenlightenment; static bool has_msr_xss; static bool has_msr_spec_ctrl; +static bool has_msr_virt_ssbd; static bool has_msr_smi_count; static uint32_t has_architectural_pmu_version; @@ -1233,6 +1234,9 @@ static int kvm_get_supported_msrs(KVMState *s) case MSR_IA32_SPEC_CTRL: has_msr_spec_ctrl = true; break; + case MSR_VIRT_SSBD: + has_msr_virt_ssbd = true; + break; } } } @@ -1721,6 +1725,10 @@ static int kvm_put_msrs(X86CPU *cpu, int level) if (has_msr_spec_ctrl) { kvm_msr_entry_add(cpu, MSR_IA32_SPEC_CTRL, env->spec_ctrl); } + if (has_msr_virt_ssbd) { + kvm_msr_entry_add(cpu, MSR_VIRT_SSBD, env->virt_ssbd); + } + #ifdef TARGET_X86_64 if (lm_capable_kernel) { kvm_msr_entry_add(cpu, MSR_CSTAR, env->cstar); @@ -2100,8 +2108,9 @@ static int kvm_get_msrs(X86CPU *cpu) if (has_msr_spec_ctrl) { kvm_msr_entry_add(cpu, MSR_IA32_SPEC_CTRL, 0); } - - + if (has_msr_virt_ssbd) { + kvm_msr_entry_add(cpu, MSR_VIRT_SSBD, 0); + } if (!env->tsc_valid) { kvm_msr_entry_add(cpu, MSR_IA32_TSC, 0); env->tsc_valid = !runstate_is_running(); @@ -2481,6 +2490,9 @@ static int kvm_get_msrs(X86CPU *cpu) case MSR_IA32_SPEC_CTRL: env->spec_ctrl = msrs[i].data; break; + case MSR_VIRT_SSBD: + env->virt_ssbd = msrs[i].data; + break; case MSR_IA32_RTIT_CTL: env->msr_rtit_ctrl = msrs[i].data; break; --- a/target/i386/machine.c +++ a/target/i386/machine.c @@ -916,6 +916,25 @@ static const VMStateDescription vmstate_msr_intel_pt = { } }; +static bool virt_ssbd_needed(void *opaque) +{ + X86CPU *cpu = opaque; + CPUX86State *env = &cpu->env; + + return env->virt_ssbd != 0; +} + +static const VMStateDescription vmstate_msr_virt_ssbd = { + .name = "cpu/virt_ssbd", + .version_id = 1, + .minimum_version_id = 1, + .needed = virt_ssbd_needed, + .fields = (VMStateField[]){ + VMSTATE_UINT64(env.virt_ssbd, X86CPU), + VMSTATE_END_OF_LIST() + } +}; + VMStateDescription vmstate_x86_cpu = { .name = "cpu", .version_id = 12, @@ -1039,6 +1058,7 @@ VMStateDescription vmstate_x86_cpu = { &vmstate_spec_ctrl, &vmstate_mcg_ext_ctl, &vmstate_msr_intel_pt, + &vmstate_msr_virt_ssbd, NULL } };