| Message ID | 20180209124638.GH13981@localhost.localdomain (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
2018-02-09 20:46 GMT+08:00 Eduardo Habkost <ehabkost@redhat.com>: > On Fri, Feb 09, 2018 at 08:24:26PM +0800, Wanpeng Li wrote: >> 2018-02-09 19:46 GMT+08:00 Eduardo Habkost <ehabkost@redhat.com>: >> > On Fri, Feb 09, 2018 at 09:41:41AM +0100, Paolo Bonzini wrote: >> >> On 08/02/2018 19:12, Eduardo Habkost wrote: >> >> > On Thu, Feb 08, 2018 at 05:44:20PM +0800, Wanpeng Li wrote: >> >> >> From: Wanpeng Li <wanpengli@tencent.com> >> >> >> >> >> >> Add PV_DEDICATED hint cpuid feature bit. >> >> >> >> >> > [...] >> >> >> diff --git a/target/i386/cpu.c b/target/i386/cpu.c >> >> >> index d70954b..cf48931 100644 >> >> >> --- a/target/i386/cpu.c >> >> >> +++ b/target/i386/cpu.c >> >> >> @@ -4076,6 +4076,9 @@ static int x86_cpu_filter_features(X86CPU *cpu) >> >> >> x86_cpu_get_supported_feature_word(w, false); >> >> >> uint32_t requested_features = env->features[w]; >> >> >> env->features[w] &= host_feat; >> >> >> + if (cpu->pv_dedicated && (w == FEAT_KVM)) { >> >> >> + env->features[w] |= CPUID_PV_DEDICATED; >> >> >> + } >> >> > >> >> > Why do this trick here instead of just adding "pv-dedicated" to >> >> > feature_word_info[FEAT_KVM].feat_names? >> >> >> >> I think because it can be added independent of KVM_GET_SUPPORTED_CPUID. >> > >> > If QEMU knows it can be enabled if outside GET_SUPPORTED_CPUID, >> > kvm_arch_get_supported_cpuid() can return it as supported. >> >> The guest fails to detect the new cpuid this time. > > This should fix it: > > diff --git a/target/i386/kvm.c b/target/i386/kvm.c > index a0aad808bd..44ee524188 100644 > --- a/target/i386/kvm.c > +++ b/target/i386/kvm.c > @@ -804,6 +804,7 @@ int kvm_arch_init_vcpu(CPUState *cs) > c = &cpuid_data.entries[cpuid_i++]; > c->function = KVM_CPUID_FEATURES | kvm_base; > c->eax = env->features[FEAT_KVM]; > + c->edx = env->features[FEAT_KVM_HINTS]; > } > > cpu_x86_cpuid(env, 0, 0, &limit, &unused, &unused, &unused); > Yeah, thanks, fold this in v2. Regards, Wanpeng Li >> >> diff --git a/target/i386/cpu.c b/target/i386/cpu.c >> index d70954b..e2974ad 100644 >> --- a/target/i386/cpu.c >> +++ b/target/i386/cpu.c >> @@ -358,6 +358,20 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = { >> .cpuid_eax = KVM_CPUID_FEATURES, .cpuid_reg = R_EAX, >> .tcg_features = TCG_KVM_FEATURES, >> }, >> + [FEAT_KVM_HINTS] = { >> + .feat_names = { >> + "hint-dedicated", NULL, NULL, NULL, >> + NULL, NULL, NULL, NULL, >> + NULL, NULL, NULL, NULL, >> + NULL, NULL, NULL, NULL, >> + NULL, NULL, NULL, NULL, >> + NULL, NULL, NULL, NULL, >> + NULL, NULL, NULL, NULL, >> + NULL, NULL, NULL, NULL, >> + }, >> + .cpuid_eax = KVM_CPUID_FEATURES, .cpuid_reg = R_EDX, >> + .tcg_features = TCG_KVM_FEATURES, >> + }, >> [FEAT_HYPERV_EAX] = { >> .feat_names = { >> NULL /* hv_msr_vp_runtime_access */, NULL /* >> hv_msr_time_refcount_access */, >> diff --git a/target/i386/cpu.h b/target/i386/cpu.h >> index f91e37d..9f73692 100644 >> --- a/target/i386/cpu.h >> +++ b/target/i386/cpu.h >> @@ -475,6 +475,7 @@ typedef enum FeatureWord { >> FEAT_8000_0008_EBX, /* CPUID[8000_0008].EBX */ >> FEAT_C000_0001_EDX, /* CPUID[C000_0001].EDX */ >> FEAT_KVM, /* CPUID[4000_0001].EAX (KVM_CPUID_FEATURES) */ >> + FEAT_KVM_HINTS, /* CPUID[4000_0001].EDX */ >> FEAT_HYPERV_EAX, /* CPUID[4000_0003].EAX */ >> FEAT_HYPERV_EBX, /* CPUID[4000_0003].EBX */ >> FEAT_HYPERV_EDX, /* CPUID[4000_0003].EDX */ >> @@ -670,6 +671,8 @@ typedef uint32_t FeatureWordArray[FEATURE_WORDS]; >> #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 KVM_HINTS_DEDICATED (1U << 0) >> + >> #define CPUID_8000_0008_EBX_IBPB (1U << 12) /* Indirect Branch >> Prediction Barrier */ >> >> #define CPUID_XSAVE_XSAVEOPT (1U << 0) >> diff --git a/target/i386/kvm.c b/target/i386/kvm.c >> index ad4b159..a0aad80 100644 >> --- a/target/i386/kvm.c >> +++ b/target/i386/kvm.c >> @@ -383,6 +383,9 @@ uint32_t kvm_arch_get_supported_cpuid(KVMState *s, >> uint32_t function, >> if (!kvm_irqchip_in_kernel()) { >> ret &= ~(1U << KVM_FEATURE_PV_UNHALT); >> } >> + } else if (function == KVM_CPUID_FEATURES && reg == R_EDX) { >> + ret |= KVM_HINTS_DEDICATED; >> + found = 1; >> } >> >> /* fallback for older kernels */ >> >> >> Regards, >> Wanpeng Li > > -- > Eduardo
diff --git a/target/i386/kvm.c b/target/i386/kvm.c index a0aad808bd..44ee524188 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -804,6 +804,7 @@ int kvm_arch_init_vcpu(CPUState *cs) c = &cpuid_data.entries[cpuid_i++]; c->function = KVM_CPUID_FEATURES | kvm_base; c->eax = env->features[FEAT_KVM]; + c->edx = env->features[FEAT_KVM_HINTS]; } cpu_x86_cpuid(env, 0, 0, &limit, &unused, &unused, &unused);