Re: [PATCH 5/6] x86: move mtrr cpu cap setting early in early_init_xxxx

[Ingo Molnar <mingo@elte.hu>]

* Krzysztof Helt <krzysztof.h1@poczta.fm> wrote:

> On Thu, 4 Sep 2008 12:17:14 -0700
> "Yinghai Lu" <yhlu.kernel@gmail.com> wrote:
> 
> > On Thu, Sep 4, 2008 at 12:13 PM, Ingo Molnar <mingo@elte.hu> wrote:
> > >
> > > * Yinghai Lu <yhlu.kernel@gmail.com> wrote:
> > >
> > >> Krzysztof Helt <krzysztof.h1@wp.pl> found mtrr is not detected on k6-2
> > >>
> > >> root case:
> > >>       we move mtrr_bp_init early for mtrr trimming.
> > >> and in early_detect, only read cap from cpuid, so some cpu doesn't have
> > >> that bit in cpuid and need to set workaround bit will have problem.
> > >>
> > >> need to add early_init_xxxx to preset those bit before mtrr_bp_init
> > >> for those earlier cpus.
> > >>
> > >> this patch is for 2.6.27
> > >
> > > hm, not sure we can do it in v2.6.27 as it depends on the other CPU init
> > > patches and that is a rather sensitive codepath. This problem should be
> > > present in v2.6.26 too, right?
> > 
> > Yes. old cpus without cpuid bit for mtrr need this patch...
> > Krzysztof Helt tested it and it works with 2.6.27-rc5 (?)
> > 
> > 
> 
> Yes, I tested the patches with 2.6.27-rc5.

ok, i've cherry-picked those two commits over into tip/x86/urgent.

	Ingo