Re: [PATCH 2/2] x86: mtrr_cleanup try gran_size to less than 1M

J.A. Magallón
2008-10-02T22:58:25Z

On Thu, 2 Oct 2008 15:33:10 -0700, "Yinghai Lu" <yinghai@kernel.org> wrote:

> On Thu, Oct 2, 2008 at 3:03 PM, J.A. Magallón <jamagallon@ono.com> wrote:
> > On Mon, 29 Sep 2008 18:54:12 -0700, Yinghai Lu <yhlu.kernel@gmail.com> wrote:
> >
> >>
> >> so start from 64k instead of 1M
> >>
> >
> > Or there is something I don't catch about mtrrs, or it still does silly
> > things.
> >
> > I have an ASUS PCDL, dual xeon, 2Gb of memory. Mtrrs after cleanup are:
> >
> > werewolf:/proc> cat mtrr
> > reg00: base=0x00000000 ( 0MB), size=1024MB: write-back, count=1
> > reg01: base=0x40000000 (1024MB), size= 512MB: write-back, count=1
> > reg02: base=0x60000000 (1536MB), size= 256MB: write-back, count=1
> > reg03: base=0x70000000 (1792MB), size= 128MB: write-back, count=1
> > reg04: base=0x78000000 (1920MB), size= 64MB: write-back, count=1
> > reg05: base=0x7c000000 (1984MB), size= 64MB: write-back, count=1
> > reg06: base=0x7ff00000 (2047MB), size= 1MB: uncachable, count=1
> >
> > So it adds a last WB zone, but substracts the last 1Mb. (Why do
> > I have that stupid uncacheable mb ? probably a bios issue...)
> > But those two 64 mb zones could be add to a 128Mb, that new one
> > with previous to 256Mb and so on, giving something like:
> >
> > reg00: base=0x00000000 ( 0MB), size=2048MB: write-back, count=1
> > reg01: base=0x7ff00000 (2047MB), size= 1MB: uncachable, count=1
> >
> > Is this incorrect ?
> >
>
> can you boot with mtrr_cleanup_debug?
>

I don't have such option in my kernel, this is -rc8-git3.

> also what is /proc/mtrr with disable_mtrr_cleanup?
>
>
Yeah, it goes right on the Xeon:

reg00: base=0x00000000 ( 0MB), size=2048MB: write-back, count=1
reg01: base=0x7ff00000 (2047MB), size= 1MB: uncachable, count=1

Will try your patch now.

--
J.A. Magallon <jamagallon()ono!com> \ Software is like sex:
\ It's better when it's free
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