i386: Don't automatically enable FEAT_KVM_HINTS bits
PATCH 1/1 i386: Don't automatically enable FEAT_KVM_HINTS bits
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 <[email protected]>
Signed-off-by Eduardo Habkost <[email protected]>
--- target/i386/cpu.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
target/i386/cpu.c +9 -1
@@ -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; } }
Signature · 1 line
2.14.3