On Tue, May 4, 2021 at 10:17 AM Sean Christopherson <seanjc@xxxxxxxxxx> wrote: > > Clear KVM's RDPID capability if the ENABLE_RDTSCP secondary exec control is > unsupported. Despite being enumerated in a separate CPUID flag, RDPID is > bundled under the same VMCS control as RDTSCP and will #UD in VMX non-root > if ENABLE_RDTSCP is not enabled. > > Fixes: 41cd02c6f7f6 ("kvm: x86: Expose RDPID in KVM_GET_SUPPORTED_CPUID") > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx> But KVM will happily emulate RDPID if the instruction causes a #UD VM-exit, won't it? See commit fb6d4d340e05 (KVM: x86: emulate RDPID).