From: Thomas Schlichter <thomas.schlichter@web.de>
To: Arjan van de Ven <arjan@linux.intel.com>
Subject: Re: [RFC Patch] use MTRR for write combining if PAT is not available
Date: Sun, 11 Oct 2009 11:56:54 +0200
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Cc: linux-kernel@vger.kernel.org, Thomas Hellstrom <thellstrom@vmware.com>
References: <200910100322.36857.thomas.schlichter@web.de> <200910101031.15620.thomas.schlichter@web.de> <4AD0ABFF.1020209@linux.intel.com>
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Arjan van de Ven wrote:
> Thomas Schlichter wrote:
> > So, convincing Ubuntu to enable PAT would be a workaround, but I think
> > the problem would still exist and should be fixed.
> 
> I think it's time to get rid of CONFIG_PAT at all.. and just have it be
>  there. Making 10+ year old CPU features that are essential functionality a
>  config option... ... not a good idea to be honest.

I do completely agree with you in this point.

But should the current behavior of not using MTRR for write combining when PAT 
is disabled (for whatever reason) stay? I think it is more consistent to do 
whatever is necessary to enable write combining when we are asked to.

Kind regards,
  Thomas
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