On Fri, 2018-02-02 at 15:28 -0500, Konrad Rzeszutek Wilk wrote: > > >  > > No. The AMD feature bits give us more fine-grained support for exposing > > IBPB or IBRS alone, so we expose those bits on Intel too. > > But but.. that runs smack against the idea of exposing a platform that > is as close to emulating the real hardware as possible. > > As in I would never expect an Intel CPU to expose the IBPB on the 0x8000_0008 > leaf. Hence KVM (nor any hypervisor) should not do it either. > > Unless Intel is doing it? Did I miss a new spec update? Are you telling me there's no way you can infer from CPUID that you're running in a hypervisor?