Re: runtime regression with "x86/mm/pat: Emulate PAT when it is disabled"

[Toshi Kani]

On Thu, 2016-03-10 at 20:20 +0100, Borislav Petkov wrote:
> On Thu, Mar 10, 2016 at 01:04:21PM -0700, Toshi Kani wrote:
> > I will send a patch that sets PAT disabled when MTRR is disabled. ÂThis
> > will solve the Paul's issue. ÂHis qemu32 model does not support PAT,
> > either.
> 
> It does, see my other mail. We need to figure out first why is
> pat_init() being called as part of MTRR setup.

I am not familiar withÂPPRO_FEATURES, but shouldn't 'flags' in
/proc/cpuinfo show "pat" whenÂX86_FEATURE_PAT is set?

pat_init() is being called as part of MTRR setup because PAT initialization
requires the same CPU rendezvous operation implemented in the MTRR code.

Thanks,
-Toshi