Re: [PATCH v2 02/13] x86/cpufeatures: add AMD Fam19h Branch Sampling feature

[Borislav Petkov]

On Thu, Nov 11, 2021 at 12:44:04AM -0800, Stephane Eranian wrote:
> This patch adds a cpu feature for AMD Fam19h Branch Sampling feature as bit

For all your commit messages:

s/This patch adds/Add/

"This patch" in a commit message is a tautology.

> 31 of EBX on CPUID leaf function 0x80000008.
> 
> Signed-off-by: Stephane Eranian <eranian@xxxxxxxxxx>
> ---
>  arch/x86/include/asm/cpufeatures.h | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
> index d5b5f2ab87a0..e71443f93f04 100644
> --- a/arch/x86/include/asm/cpufeatures.h
> +++ b/arch/x86/include/asm/cpufeatures.h
> @@ -315,6 +315,7 @@
>  #define X86_FEATURE_AMD_SSBD		(13*32+24) /* "" Speculative Store Bypass Disable */
>  #define X86_FEATURE_VIRT_SSBD		(13*32+25) /* Virtualized Speculative Store Bypass Disable */
>  #define X86_FEATURE_AMD_SSB_NO		(13*32+26) /* "" Speculative Store Bypass is fixed in hardware. */
> +#define X86_FEATURE_AMD_BRS		(13*32+31) /* Branch Sampling available */

	X86_FEATURE_BRS

is perfectly fine - there's no need to say "amd_brs" in /proc/cpuinfo on
AMD machines as this is where this flag will be only set.

Thx.

-- 
Regards/Gruss,
    Boris.

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