Add a framework to manage and cache KVM-governed features, i.e. CPUID
based features that require explicit KVM enabling and/or need to be
queried semi-frequently by KVM. The idea originally came up in the
context of the architectural LBRs series as a way to avoid querying
guest CPUID in hot paths without needing a dedicated flag, but as
evidenced by the shortlog, the most common usage is to handle the ever-
growing list of SVM features that are exposed to L1.
Note, I don't like the name "governed", but it was the least awful thing I
could come up with. Suggestions most definitely welcome.
This series is lightly tested. I am posting somewhat speculatively to get
early feedback on the idea.
Sean Christopherson (12):
KVM: x86: Add a framework for enabling KVM-governed x86 features
KVM: x86/mmu: Use KVM-governed feature framework to track "GBPAGES
enabled"
KVM: VMX: Recompute "XSAVES enabled" only after CPUID update
KVM: VMX: Rename XSAVES control to follow KVM's preferred "ENABLE_XYZ"
KVM: x86: Use KVM-governed feature framework to track "XSAVES enabled"
KVM: nSVM: Use KVM-governed feature framework to track "NRIPS enabled"
KVM: nSVM: Use KVM-governed feature framework to track "TSC scaling
enabled"
KVM: nSVM: Use KVM-governed feature framework to track "vVM{SAVE,LOAD}
enabled"
KVM: nSVM: Use KVM-governed feature framework to track "LBRv enabled"
KVM: nSVM: Use KVM-governed feature framework to track "Pause Filter
enabled"
KVM: nSVM: Use KVM-governed feature framework to track "vGIF enabled"
KVM: x86: Disallow guest CPUID lookups when IRQs are disabled
arch/x86/include/asm/kvm_host.h | 11 ++++++
arch/x86/include/asm/vmx.h | 2 +-
arch/x86/kvm/cpuid.c | 31 +++++++++++++++++
arch/x86/kvm/cpuid.h | 51 ++++++++++++++++++++++++++++
arch/x86/kvm/governed_features.h | 19 +++++++++++
arch/x86/kvm/mmu/mmu.c | 20 ++---------
arch/x86/kvm/svm/nested.c | 48 ++++++++++++++++-----------
arch/x86/kvm/svm/svm.c | 57 +++++++++++++++++++++-----------
arch/x86/kvm/svm/svm.h | 13 ++------
arch/x86/kvm/vmx/capabilities.h | 2 +-
arch/x86/kvm/vmx/hyperv.h | 2 +-
arch/x86/kvm/vmx/nested.c | 6 ++--
arch/x86/kvm/vmx/nested.h | 2 +-
arch/x86/kvm/vmx/vmx.c | 48 +++++++++++++--------------
arch/x86/kvm/vmx/vmx.h | 2 +-
arch/x86/kvm/x86.c | 4 +--
16 files changed, 217 insertions(+), 101 deletions(-)
create mode 100644 arch/x86/kvm/governed_features.h
base-commit: 62ef199250cd46fb66fe98267137b7f64e0b41b4
--
2.39.2.637.g21b0678d19-goog
