| Message ID | 20180410211534.26079-1-ehabkost@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | [for-2.12] i386: Don't automatically enable FEAT_KVM_HINTS bits | expand |
2018-04-11 5:15 GMT+08:00 Eduardo Habkost <ehabkost@redhat.com>: > The assumption in the cpu->max_features code is that anything > enabled on GET_SUPPORTED_CPUID should be enabled on "-cpu host". > This shouldn't be the case for FEAT_KVM_HINTS. > > This adds a new FeatureWordInfo::no_autoenable_flags field, that > can be used to prevent FEAT_KVM_HINTS bits to be enabled > automatically. > > Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> > Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Thanks for the patch, Eduardo! Tested-by: Wanpeng Li <wanpengli@tencent.com> Regards, Wanpeng Li > --- > target/i386/cpu.c | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/target/i386/cpu.c b/target/i386/cpu.c > index 1a6b082b6f..a20fe26573 100644 > --- a/target/i386/cpu.c > +++ b/target/i386/cpu.c > @@ -295,6 +295,8 @@ typedef struct FeatureWordInfo { > uint32_t tcg_features; /* Feature flags supported by TCG */ > uint32_t unmigratable_flags; /* Feature flags known to be unmigratable */ > uint32_t migratable_flags; /* Feature flags known to be migratable */ > + /* Features that shouldn't be auto-enabled by "-cpu host" */ > + uint32_t no_autoenable_flags; > } FeatureWordInfo; > > static FeatureWordInfo feature_word_info[FEATURE_WORDS] = { > @@ -400,6 +402,11 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = { > }, > .cpuid_eax = KVM_CPUID_FEATURES, .cpuid_reg = R_EDX, > .tcg_features = TCG_KVM_FEATURES, > + /* > + * KVM hints aren't auto-enabled by -cpu host, they need to be > + * explicitly enabled in the command-line. > + */ > + .no_autoenable_flags = ~0U, > }, > [FEAT_HYPERV_EAX] = { > .feat_names = { > @@ -4062,7 +4069,8 @@ static void x86_cpu_expand_features(X86CPU *cpu, Error **errp) > */ > env->features[w] |= > x86_cpu_get_supported_feature_word(w, cpu->migratable) & > - ~env->user_features[w]; > + ~env->user_features[w] & \ > + ~feature_word_info[w].no_autoenable_flags; > } > } > > -- > 2.14.3 >
diff --git a/target/i386/cpu.c b/target/i386/cpu.c index 1a6b082b6f..a20fe26573 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -295,6 +295,8 @@ typedef struct FeatureWordInfo { uint32_t tcg_features; /* Feature flags supported by TCG */ uint32_t unmigratable_flags; /* Feature flags known to be unmigratable */ uint32_t migratable_flags; /* Feature flags known to be migratable */ + /* Features that shouldn't be auto-enabled by "-cpu host" */ + uint32_t no_autoenable_flags; } FeatureWordInfo; static FeatureWordInfo feature_word_info[FEATURE_WORDS] = { @@ -400,6 +402,11 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = { }, .cpuid_eax = KVM_CPUID_FEATURES, .cpuid_reg = R_EDX, .tcg_features = TCG_KVM_FEATURES, + /* + * KVM hints aren't auto-enabled by -cpu host, they need to be + * explicitly enabled in the command-line. + */ + .no_autoenable_flags = ~0U, }, [FEAT_HYPERV_EAX] = { .feat_names = { @@ -4062,7 +4069,8 @@ static void x86_cpu_expand_features(X86CPU *cpu, Error **errp) */ env->features[w] |= x86_cpu_get_supported_feature_word(w, cpu->migratable) & - ~env->user_features[w]; + ~env->user_features[w] & \ + ~feature_word_info[w].no_autoenable_flags; } }