KVM: x86: prevent MWAIT in guest with buggy MONITOR
The bug prevents MWAIT from waking up after a write to the monitored
cache line.
KVM might emulate a CPU model that shouldn't have the bug, so the guest
would not employ a workaround and possibly miss wakeups.
Better to avoid the situation.
Reviewed-by: Alexander Graf <agraf@suse.de> Acked-by: Borislav Petkov <bp@suse.de> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>