[PATCH v3 0/4] KVM: x86: Virtualize AMD's "disable CPUID in usermode"

[Jim Mattson]

AMD's "disable CPUID in usermode" feature is analogous to Intel's "CPUID
faulting" feature, but it is advertised and activated differently.  The AMD
feature is advertised via CPUID.80000021H:EAX.CpuidUserDis[bit 17] and
activated by setting HWCR.CpuidUserDis[bit 35].

Add virtualization support for the AMD feature.

v2 -> v3:
* Logic consolidation between emulator and CPUID VM-exit handler [Sean]
* Define MSR_K7_HWCR_CPUID_USER_DIS
* Keep u64 in the selftest (oops)
* Fixe the selftest failre on Intel hosts

v1: https://lore.kernel.org/kvm/20260402223108.650572-1-jmattson@xxxxxxxxxx/
v2: https://lore.kernel.org/kvm/20260508170714.489136-1-jmattson@xxxxxxxxxx/

Jim Mattson (3):
  KVM: x86: Remove supports_cpuid_fault() helper
  KVM: x86: Virtualize AMD CPUID faulting
  KVM: selftests: Update hwcr_msr_test for CPUID faulting bit

Sean Christopherson (1):
  KVM: x86: Consolidate CPUID fault handling for emulator and
    interception logic

 arch/x86/include/asm/kvm_host.h               |  1 -
 arch/x86/include/asm/msr-index.h              |  1 +
 arch/x86/kvm/cpuid.c                          |  7 ++--
 arch/x86/kvm/cpuid.h                          | 14 ++++---
 arch/x86/kvm/emulate.c                        |  6 +--
 arch/x86/kvm/kvm_emulate.h                    |  1 +
 arch/x86/kvm/x86.c                            | 38 +++++++++----------
 .../selftests/kvm/include/x86/processor.h     |  1 +
 .../testing/selftests/kvm/x86/hwcr_msr_test.c |  9 ++++-
 9 files changed, 43 insertions(+), 35 deletions(-)


base-commit: 85f871f6ba46f20d7fbc0b016b4db648c33220dd
-- 
2.54.0.631.ge1b05301d1-goog