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Date: Wed, 21 Jan 2009 12:25:30 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: hpa@zytor.com, tglx@linutronix.de, torvalds@linux-foundation.org,
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Subject: Re: [patch] x86: fix page attribute corruption with cpa()
Message-ID: <20090121112530.GD23469@elte.hu>
References: <20090120222021.GB28352@linux-os.sc.intel.com>
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* Suresh Siddha <suresh.b.siddha@intel.com> wrote:

> This patch fixes a performance issue reported by Linus on his Nehalem 
> system. While Linus reverted the PAT patch (commit 
> 58dab916dfb57328d50deb0aa9b3fc92efa248ff) which exposed the issue, 
> existing cpa() code can potentially still cause wrong(page attribute 
> corruption) behavior.
> 
> This patch also fixes the "WARNING: at arch/x86/mm/pageattr.c:560" that 
> various people reported.

nice fix - applied to tip/x86/urgent, thanks Suresh!

	Ingo