Re: [Qemu-devel] [PATCH 09/20] target-i386: move kvm_check_features_against_host() check to realize time

[Eduardo Habkost]

On Mon, Dec 17, 2012 at 05:01:21PM +0100, Igor Mammedov wrote:
> Signed-off-by: Igor Mammedov <address@hidden>

Reviewed-by: Eduardo Habkost <address@hidden>

I really like this one, because it makes it easy to unify
filter_features_for_kvm() and kvm_check_features_against_host() later.


> ---
>  target-i386/cpu.c |   23 ++++++++++++-----------
>  1 files changed, 12 insertions(+), 11 deletions(-)
> 
> diff --git a/target-i386/cpu.c b/target-i386/cpu.c
> index 24bfd95..e075b59 100644
> --- a/target-i386/cpu.c
> +++ b/target-i386/cpu.c
> @@ -951,19 +951,20 @@ static int unavailable_host_feature(struct 
> model_features_t *f, uint32_t mask)
>   *
>   * This function may be called only if KVM is enabled.
>   */
> -static int kvm_check_features_against_host(x86_def_t *guest_def)
> +static int kvm_check_features_against_host(X86CPU *cpu)
>  {
> +    CPUX86State *env = &cpu->env;
>      x86_def_t host_def;
>      uint32_t mask;
>      int rv, i;
>      struct model_features_t ft[] = {
> -        {&guest_def->features, &host_def.features,
> +        {&env->cpuid_features, &host_def.features,
>              ~0, feature_name, 0x00000000},
> -        {&guest_def->ext_features, &host_def.ext_features,
> +        {&env->cpuid_ext_features, &host_def.ext_features,
>              ~CPUID_EXT_HYPERVISOR, ext_feature_name, 0x00000001},
> -        {&guest_def->ext2_features, &host_def.ext2_features,
> +        {&env->cpuid_ext2_features, &host_def.ext2_features,
>              ~PPRO_FEATURES, ext2_feature_name, 0x80000000},
> -        {&guest_def->ext3_features, &host_def.ext3_features,
> +        {&env->cpuid_ext3_features, &host_def.ext3_features,
>              ~CPUID_EXT3_SVM, ext3_feature_name, 0x80000001}};
>  
>      assert(kvm_enabled());
> @@ -1428,12 +1429,6 @@ static int cpu_x86_parse_featurestr(x86_def_t 
> *x86_cpu_def, char *features)
>      x86_cpu_def->kvm_features &= ~minus_kvm_features;
>      x86_cpu_def->svm_features &= ~minus_svm_features;
>      x86_cpu_def->cpuid_7_0_ebx_features &= ~minus_7_0_ebx_features;
> -#ifdef CONFIG_KVM
> -    if (check_cpuid && kvm_enabled()) {
> -        if (kvm_check_features_against_host(x86_cpu_def) && enforce_cpuid)
> -            goto error;
> -    }
> -#endif
>      return 0;
>  
>  error:
> @@ -2106,6 +2101,12 @@ void x86_cpu_realize(Object *obj, Error **errp)
>          env->cpuid_svm_features &= TCG_SVM_FEATURES;
>      } else {
>  #ifdef CONFIG_KVM
> +        if (check_cpuid && kvm_check_features_against_host(cpu)
> +            && enforce_cpuid) {
> +            error_setg(errp, "Host's CPU doesn't support requested 
> features");
> +            return;
> +        }
> +
>          filter_features_for_kvm(cpu);
>  #endif
>      }
> -- 
> 1.7.1
> 
> 

-- 
Eduardo