Re: [RFC Patch] use MTRR for write combining if PAT is notavailable

[Ingo Molnar]

* Thomas Schlichter <thomas.schlichter@xxxxxx> wrote:

> I don't think this is a good idea, Robert Hancock wrote there may be 
> millions of such Laptops (Core Solo/Duo erratum AE7, Pentium M erratum 
> Y31) :
>
>   http://marc.info/?l=linux-kernel&m=125537136105246&w=2
> 
> > or Perhaps just try to add mtrr only for the pci mmap case like the 
> > 4th patch in this series..
> 
> I'd prefer this! ;-)

Hm, we could perhaps do that - but i think we should only do that on 
systems that have PAT disabled.

Which brings up the question of how to properly QA such a narrow segment 
of the market. Maybe disabling CONFIG_X86_PAT should enable that logic 
too.

	Ingo
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