Re: [PATCH 0/4] KVM: x86: kvm_mwait_in_guest() cleanup and fixes

From: Gabriel L. Somlo
Date: Thu May 04 2017 - 13:56:55 EST

Hi Radim,

On Wed, May 03, 2017 at 09:37:29PM +0200, Radim KrÄmÃÅ wrote:
> kvm_mwait_in_guest() was overcomplicated and also missed one AMD bug
> that should prevent MWAIT pass through.
> This series ignores errata that don't have any Linux bug defined;
> I know of two minor (not affecting the host) Core 2 errata:
> AG36. Split Locked Stores May not Trigger the Monitoring Hardware
> AG106. A REP STOS/MOVS to a MONITOR/MWAIT Address Range May Prevent
> Triggering of the Monitoring Hardware
> None of them are really worthy of a new condition if Linux never hit
> them ... we still have the OS X bug that Gabriel is hitting, but I'm ok
> with the original approach that sacrificed it for "greater good".

If I wanted to test this (e.g. with OS X 10.8 guests on several of my older
Mac boxes running Fedora), which git repo would you have me use? (The series
won't apply directly on top of git://

Thanks much,

> Radim KrÄmÃÅ (4):
> KVM: svm: prevent MWAIT in guest with erratum 400
> KVM: x86: prevent MWAIT in guest with buggy MONITOR
> KVM: x86: drop bogus MWAIT check
> KVM: x86: simplify kvm_mwait_in_guest()
> arch/x86/kvm/x86.h | 33 +++------------------------------
> 1 file changed, 3 insertions(+), 30 deletions(-)
> --
> 2.12.2