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

["Yinghai Lu" <yinghai@kernel.org>]

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?

also what is /proc/mtrr with disable_mtrr_cleanup?

YH