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Date: Thu, 8 May 2008 16:32:50 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Andi Kleen <andi@firstfloor.org>
Cc: Rene Herman <rene.herman@keyaccess.nl>,
       Linus Torvalds <torvalds@linux-foundation.org>,
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       Ingo Molnar <mingo@elte.hu>,
       Linux Kernel <linux-kernel@vger.kernel.org>, akpm@linux-foundation.org,
       Pavel Machek <pavel@suse.cz>
Subject: Re: [PATCH] x86: introduce a new Linux defined feature flag for PAT
 support
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> For old CPUs it is actually ok (after all they worked for years without
> PAT), I just don't like it for new CPUs. It's a bad idea there and
> in the x86 world it is a reasonable expectation that CPU features
> generally work.

Agreed 100%. We should default to assuming newer processors work. That
will be true in almost if not all cases anyway, and since it'll bite
anyone at Intel/AMD/.. testing new CPU steppings when it is on by default
any problem cases won't be leaving the labs.

Alan