[libvirt] [PATCH qom-cpu-next 2/3] target-i386: Introduce X86CPU.filtered_features field

This field will contain the feature bits that were filtered out because of missing host support. Signed-off-by: Eduardo Habkost <ehabkost(a)redhat.com&gt; Reviewed-by: Eric Blake <eblake(a)redhat.com&gt; --- Changes v11 -> v12: * Rebase on top of qom-cpu-next (commit bd87d2a - target-i386: Use FeatureWord loop on filter_features_for_kvm()) --- target-i386/cpu-qom.h | 3 +++ target-i386/cpu.c | 9 ++++++--- 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/target-i386/cpu-qom.h b/target-i386/cpu-qom.h index f890f1c..849cedf 100644 --- a/target-i386/cpu-qom.h +++ b/target-i386/cpu-qom.h @@ -65,6 +65,9 @@ typedef struct X86CPU { /*< public >*/ CPUX86State env; + + /* Features that were filtered out because of missing host capabilities */ + uint32_t filtered_features[FEATURE_WORDS]; } X86CPU; static inline X86CPU *x86_env_get_cpu(CPUX86State *env) diff --git a/target-i386/cpu.c b/target-i386/cpu.c index 3857514..38793bc 100644 --- a/target-i386/cpu.c +++ b/target-i386/cpu.c @@ -1698,9 +1698,12 @@ static void filter_features_for_kvm(X86CPU *cpu) for (w = 0; w < FEATURE_WORDS; w++) { FeatureWordInfo *wi = &feature_word_info[w]; - env->features[w] &= kvm_arch_get_supported_cpuid(s, wi->cpuid_eax, - wi->cpuid_ecx, - wi->cpuid_reg); + uint32_t host_feat = kvm_arch_get_supported_cpuid(s, wi->cpuid_eax, + wi->cpuid_ecx, + wi->cpuid_reg); + uint32_t requested_features = env->features[w]; + env->features[w] &= host_feat; + cpu->filtered_features[w] = requested_features & ~env->features[w]; } } #endif -- 1.8.1.4