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

[Kim Phillips]

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@xxxxxxx/

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(-)

-- 
2.34.1