diff options
| author | Sean Christopherson <seanjc@google.com> | 2022-06-08 22:45:12 +0000 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-06-20 11:50:42 -0400 |
| commit | bfbcc81bb82cbbad8bf4e40cea274f42b50674e2 (patch) | |
| tree | 644d8901c84e9720c22a819b706773951201e31c /tools/testing/selftests/kvm/lib/x86_64/processor.c | |
| parent | ff81a90f45ce6b818167c590f7625b3b573defc9 (diff) | |
| download | linux-bfbcc81bb82cbbad8bf4e40cea274f42b50674e2.tar.bz2 | |
KVM: x86: Add a quirk for KVM's "MONITOR/MWAIT are NOPs!" behavior
Add a quirk for KVM's behavior of emulating intercepted MONITOR/MWAIT
instructions a NOPs regardless of whether or not they are supported in
guest CPUID. KVM's current behavior was likely motiviated by a certain
fruity operating system that expects MONITOR/MWAIT to be supported
unconditionally and blindly executes MONITOR/MWAIT without first checking
CPUID. And because KVM does NOT advertise MONITOR/MWAIT to userspace,
that's effectively the default setup for any VMM that regurgitates
KVM_GET_SUPPORTED_CPUID to KVM_SET_CPUID2.
Note, this quirk interacts with KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT. The
behavior is actually desirable, as userspace VMMs that want to
unconditionally hide MONITOR/MWAIT from the guest can leave the
MISC_ENABLE quirk enabled.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220608224516.3788274-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'tools/testing/selftests/kvm/lib/x86_64/processor.c')
0 files changed, 0 insertions, 0 deletions