[PATCH v2 1/2] x86/cpufeatures: Add "Allowed SEV Features" Feature

Kim Phillips
2024-08-22T22:20:06Z

Add CPU feature detection for "Allowed SEV Features" to allow the
Hypervisor to enforce that SEV-ES and SEV-SNP guest VMs cannot
enable features (via SEV_FEATURES) that the Hypervisor does not
support or wish to be enabled.

Signed-off-by: Kishon Vijay Abraham I <kvijayab@amd.com>
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
---
v2: no changes

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 dd4682857c12..0c73da91a041 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -447,6 +447,7 @@
#define X86_FEATURE_V_TSC_AUX (19*32+ 9) /* Virtual TSC_AUX */
#define X86_FEATURE_SME_COHERENT (19*32+10) /* AMD hardware-enforced cache coherency */
#define X86_FEATURE_DEBUG_SWAP (19*32+14) /* "debug_swap" AMD SEV-ES full debug state swap support */
+#define X86_FEATURE_ALLOWED_SEV_FEATURES (19*32+27) /* AMD Allowed SEV Features */
#define X86_FEATURE_SVSM (19*32+28) /* "svsm" SVSM present */

/* AMD-defined Extended Feature 2 EAX, CPUID level 0x80000021 (EAX), word 20 */
--
2.34.1