Changes since v2: - "x86/hyperv: Add HV_INVARIANT_TSC_EXPOSED define" patch added [Sean] - "KVM: x86: Introduce CPUID_8000_0007_EDX 'scattered' leaf" [Sean]. Hope I got all that magic right... - s,hv_invtsc,hv_invtsc_control, [Sean] - s,should_not_gp,fault_expected, and invert the logic [Sean] - "KVM: selftests: Convert hyperv_features test to using KVM_X86_CPU_FEATURE()" patch added. - Switch the newly introduced selftest to KVM_X86_CPU_FEATURE [Sean] - Other minor selftest adjustments [Sean] Original description: Normally, genuine Hyper-V doesn't expose architectural invariant TSC (CPUID.80000007H:EDX[8]) to its guests by default. A special PV MSR (HV_X64_MSR_TSC_INVARIANT_CONTROL, 0x40000118) and corresponding CPUID feature bit (CPUID.0x40000003.EAX[15]) were introduced. When bit 0 of the PV MSR is set, invariant TSC bit starts to show up in CPUID. When the feature is exposed to Hyper-V guests, reenlightenment becomes unneeded. Note: strictly speaking, KVM doesn't have to have the feature as exposing raw invariant TSC bit (CPUID.80000007H:EDX[8]) also seems to work for modern Windows versions. The feature is, however, tiny and straitforward and gives additional flexibility so why not. Vitaly Kuznetsov (6): x86/hyperv: Add HV_INVARIANT_TSC_EXPOSED define KVM: x86: Introduce CPUID_8000_0007_EDX 'scattered' leaf KVM: x86: Hyper-V invariant TSC control KVM: selftests: Rename 'msr->availble' to 'msr->fault_exepected' in hyperv_features test KVM: selftests: Convert hyperv_features test to using KVM_X86_CPU_FEATURE() KVM: selftests: Test Hyper-V invariant TSC control arch/x86/include/asm/hyperv-tlfs.h | 3 + arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kernel/cpu/mshyperv.c | 2 +- arch/x86/kvm/cpuid.c | 7 + arch/x86/kvm/hyperv.c | 19 ++ arch/x86/kvm/hyperv.h | 15 ++ arch/x86/kvm/reverse_cpuid.h | 9 +- arch/x86/kvm/x86.c | 4 +- .../selftests/kvm/include/x86_64/hyperv.h | 144 ++++++++---- .../selftests/kvm/include/x86_64/processor.h | 1 + .../selftests/kvm/x86_64/hyperv_features.c | 212 +++++++++++------- 11 files changed, 281 insertions(+), 136 deletions(-) -- 2.37.2