On Fri, 02 Aug 2024 11:55:02 -0700, Sean Christopherson wrote: > The primary goal of this series to fix an issue where KVM's initialization > of feature MSRs during vCPU creation results in a failed save/restore of > PERF_CAPABILITIES. If userspace configures the VM to _not_ have a PMU, > because KVM initializes the vCPU's PERF_CAPABILTIIES, trying to save/restore > the non-zero value will be rejected by the destination. > > The secondary goal is to try and avoid such goofs in the future, by making > it explicitly clear that userspace owns the vCPU model. > > [...] Applied to kvm-x86 misc, thanks! [1/9] KVM: x86: Co-locate initialization of feature MSRs in kvm_arch_vcpu_create() https://github.com/kvm-x86/linux/commit/383383cfd202 [2/9] KVM: x86: Disallow changing MSR_PLATFORM_INFO after vCPU has run https://github.com/kvm-x86/linux/commit/d76a5e78f16d [3/9] KVM: x86: Quirk initialization of feature MSRs to KVM's max configuration https://github.com/kvm-x86/linux/commit/088b8eeb25ec [4/9] KVM: x86: Reject userspace attempts to access PERF_CAPABILITIES w/o PDCM https://github.com/kvm-x86/linux/commit/c2eb2d0318c0 [5/9] KVM: VMX: Remove restriction that PMU version > 0 for PERF_CAPABILITIES https://github.com/kvm-x86/linux/commit/bae593b20e92 [6/9] KVM: x86: Reject userspace attempts to access ARCH_CAPABILITIES w/o support https://github.com/kvm-x86/linux/commit/83a5fe6cf1eb [7/9] KVM: x86: Remove ordering check b/w MSR_PLATFORM_INFO and MISC_FEATURES_ENABLES https://github.com/kvm-x86/linux/commit/9d2dcfb82db1 [8/9] KVM: selftests: Verify get/set PERF_CAPABILITIES w/o guest PDMC behavior https://github.com/kvm-x86/linux/commit/6a4511f8602f [9/9] KVM: selftests: Add a testcase for disabling feature MSRs init quirk https://github.com/kvm-x86/linux/commit/58a7368f104d -- https://github.com/kvm-x86/linux/tree/next