Re: [PATCH] <sys/platform/x86.h>: Add APX support

[Florian Weimer <fweimer@redhat.com>]

* H. J. Lu via Libc-alpha:

> diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
> index 9ac195810f..376e3c7501 100644
> --- a/sysdeps/x86/cpu-features.c
> +++ b/sysdeps/x86/cpu-features.c
> @@ -226,6 +226,10 @@ update_active (struct cpu_features *cpu_features)
>  	  CPU_FEATURE_SET_ACTIVE (cpu_features, AMX_COMPLEX);
>  	}
>  
> +      /* Is AVX state usable?  */
> +      if ((xcrlow & bit_AVX_state) != 0)
> +	CPU_FEATURE_SET_ACTIVE (cpu_features, APX_F);
> +
>        /* These features are usable only when OSXSAVE is enabled.  */
>        CPU_FEATURE_SET (cpu_features, XSAVE);
>        CPU_FEATURE_SET_ACTIVE (cpu_features, XSAVEOPT);

AVX vs APX looks like a typo, this needs a comment.

Will this really work without further kernel enablement?  Finally a
compelling use case for MPX. 8-)

Thanks,
Floria