Re: [patch] x86: Fix /dev/mem mmap breakage when PAT is disabled

From: Arjan van de Ven
Date: Thu Oct 30 2008 - 17:29:38 EST


On Thu, 30 Oct 2008 14:21:21 -0700
Ravikiran G Thirumalai <kiran@xxxxxxxxxxxx> wrote:

> On Thu, Oct 30, 2008 at 01:21:03PM -0700, Arjan van de Ven wrote:
> >On Wed, 29 Oct 2008 19:02:03 -0700
> >Ravikiran G Thirumalai <kiran@xxxxxxxxxxxx> wrote:
> >
> >well... technically the aliases are bad without PAT as well...
> >
>
> Hmm! Well, you mean if mtrr is used to change attributes?

you can also set uncached in the pagetables, like via ioremap_uncached
and other ways.

and /dev/mem may or may not imply cached/uncached, depending on the
open flags.

On memory... what would that mean?

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Arjan van de Ven Intel Open Source Technology Centre
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