[PATCH v2 0/2] KVM: SEV: Add support for the ALLOWED_SEV_FEATURES feature

Kim Phillips
2024-08-22T22:19:55Z

AMD EPYC 5th generation processors have introduced a feature that allows
the hypervisor to control the SEV_FEATURES that are set for, or by, a
guest. ALLOWED_SEV_FEATURES can be used by the hypervisor to enforce
that SEV-ES and SEV-SNP guests cannot enable features that the
hypervisor does not want to be enabled.

Patch 1/2 adds support to detect the feature.

Patch 2/2 configures the ALLOWED_SEV_FEATURES field in the VMCB
according to the features the hypervisor supports.

Based on tip/master commit a2767e7f31ad ("Merge branch into tip/master: 'x86/timers'")

v2:
- Added some SEV_FEATURES require to be explicitly allowed by
ALLOWED_SEV_FEATURES wording (Sean).
- Added Nikunj's Reviewed-by.

v1:
https://lore.kernel.org/lkml/20240802015732.3192877-1-kim.phillips@amd.com/

Kim Phillips (2):
x86/cpufeatures: Add "Allowed SEV Features" Feature
KVM: SEV: Configure "ALLOWED_SEV_FEATURES" VMCB Field

arch/x86/include/asm/cpufeatures.h | 1 +
arch/x86/include/asm/svm.h | 6 +++++-
arch/x86/kvm/svm/sev.c | 5 +++++
3 files changed, 11 insertions(+), 1 deletion(-)

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2.34.1