Re: [RFC PATCH v3 05/27] x86/cpufeatures: Add Secure AVIC CPU feature

From: Tom Lendacky

Date: Mon Jul 13 2026 - 14:33:00 EST


On 7/8/26 01:32, Naveen N Rao (AMD) wrote:
> From: Neeraj Upadhyay <Neeraj.Upadhyay@xxxxxxx>
>
> Add CPU feature detection for Secure AVIC. The Secure AVIC feature
> provides hardware acceleration for performance sensitive APIC accesses
> and support for managing guest-owned APIC state for the SEV-SNP guests.
>
> Co-developed-by: Kishon Vijay Abraham I <kvijayab@xxxxxxx>
> Signed-off-by: Kishon Vijay Abraham I <kvijayab@xxxxxxx>
> Signed-off-by: Neeraj Upadhyay <Neeraj.Upadhyay@xxxxxxx>

Reviewed-by: Tom Lendacky <thomas.lendacky@xxxxxxx>

> ---
> 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 35a2a0f9ab32..d538db618f24 100644
> --- a/arch/x86/include/asm/cpufeatures.h
> +++ b/arch/x86/include/asm/cpufeatures.h
> @@ -457,6 +457,7 @@
> #define X86_FEATURE_DEBUG_SWAP (19*32+14) /* "debug_swap" SEV-ES full debug state swap support */
> #define X86_FEATURE_RMPREAD (19*32+21) /* RMPREAD instruction */
> #define X86_FEATURE_SEGMENTED_RMP (19*32+23) /* Segmented RMP support */
> +#define X86_FEATURE_SNP_SECURE_AVIC (19*32+26) /* SEV-SNP Secure AVIC */
> #define X86_FEATURE_ALLOWED_SEV_FEATURES (19*32+27) /* Allowed SEV Features */
> #define X86_FEATURE_SVSM (19*32+28) /* "svsm" SVSM present */
> #define X86_FEATURE_HV_INUSE_WR_ALLOWED (19*32+30) /* Allow Write to in-use hypervisor-owned pages */