> It does not make any sense to even try to access the chicken bits > MSRs when running under virtualization. It is the duty of the > hypervisor to configure hardware.I would tend to agree with you :-) I was kind of surprised to read that they are actually saved and restored as part of a VM context switch in fact.> I updated the patch.Thanks I shall try this now on my workstation and the Epyc virtual machine -pete.
Konstantin Belousov
2018-Jul-05 10:47 UTC
Ryzen issues on FreeBSD ? (with sort of workaround)
On Thu, Jul 05, 2018 at 11:43:29AM +0100, Pete French wrote:> > It does not make any sense to even try to access the chicken bits > > MSRs when running under virtualization. It is the duty of the > > hypervisor to configure hardware. > > I would tend to agree with you :-) I was kind of surprised to read that they > are actually saved and restored as part of a VM context switch in fact.Why do you state that they are saved/restored ? What is the evidence ?> > > I updated the patch. > > Thanks I shall try this now on my workstation and the Epyc virtual machineOn VM the patch should be NOP, testing it is a waste of time IMO.