Re: [PATCH v10 2/6] x86/sev: Initialize RMPOPT configuration MSRs

[Borislav Petkov]

On Mon, Jul 20, 2026 at 05:38:05PM -0500, Kalra, Ashish wrote:
> Agreed on dropping the bool — I'll derive it in a local helper.
> 
> One issue though: rmp_segment_table != NULL isn't segmented-only. setup_contiguous_rmptable() also allocates rmp_segment_table
> (the contiguous RMP is stored as a single segment in the same table), so it's non-NULL for the contiguous case too.
> 
> To keep it segmented-only, I'll also need to gate on the segmented-RMP mode, something like: 
> 
>   static bool rmpopt_capable(void)
>   {
>         return cpu_feature_enabled(X86_FEATURE_RMPOPT) &&
>                cc_platform_has(CC_ATTR_HOST_SEV_SNP) &&
>                (rmp_cfg & MSR_AMD64_SEG_RMP_ENABLED) &&
>                rmp_segment_table;
>   }
> 
> The CC_ATTR_HOST_SEV_SNP check also handles SNP being disabled at runtime, so snp_clear_rmpopt_capable() and its caller go away as well.

Ok, you can simply do:

	setup_clear_cpu_cap(X86_FEATURE_RMPOPT)

and clear our internal representation of RMPOPT support and make it a lot
simpler.

-- 
Regards/Gruss,
    Boris.

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