Re: [PATCH v6 1/6] x86/cpufeatures: Add X86_FEATURE_AMD_RMPOPT feature flag

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Medium] Mismatch between the feature flag name in the commit message title and the actual code.
- [Low] Missing synchronization of `arch/x86/include/asm/cpufeatures.h` with the corresponding tools copy.
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commit c36f3189418bf1ed5bdfdcfed5326214cecfd96a
Author: Ashish Kalra <ashish.kalra@amd.com>

x86/cpufeatures: Add X86_FEATURE_AMD_RMPOPT feature flag

This commit adds a new feature flag indicating whether the RMPOPT
instruction is supported. It allows RMP checks to be skipped when 1-GB
memory regions are known to contain no SEV-SNP guest memory.

> x86/cpufeatures: Add X86_FEATURE_AMD_RMPOPT feature flag

[Severity: Medium]
The commit message title states it adds the X86_FEATURE_AMD_RMPOPT feature
flag, but the code implementation defines it as X86_FEATURE_RMPOPT (without
the AMD_ prefix). Should the commit title be updated to accurately reflect
the macro name defined in the code?

> diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
> index 1b4a48bff18f7..14f23d19d8645 100644
> --- a/arch/x86/include/asm/cpufeatures.h
> +++ b/arch/x86/include/asm/cpufeatures.h
> @@ -76,7 +76,7 @@
>  #define X86_FEATURE_K8			( 3*32+ 4) /* Opteron, Athlon64 */
>  #define X86_FEATURE_ZEN5		( 3*32+ 5) /* CPU based on Zen5 microarchitecture */
>  #define X86_FEATURE_ZEN6		( 3*32+ 6) /* CPU based on Zen6 microarchitecture */
> -/* Free                                 ( 3*32+ 7) */
> +#define X86_FEATURE_RMPOPT		( 3*32+ 7) /* Support for AMD RMPOPT instruction */

[Severity: Low]
Does this update need to be mirrored in
tools/arch/x86/include/asm/cpufeatures.h?

Adding a new CPU feature flag to the kernel header without updating the tools
copy typically causes tools like perf and the check-headers.sh script to emit
build warnings about the kernel ABI header differing from the latest version.

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Sashiko AI review · https://sashiko.dev/#/patchset/cover.1780427587.git.ashish.kalra@amd.com?part=1