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Date: Tue, 16 Jun 2009 10:54:15 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
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cc: linux-tip-commits@vger.kernel.org
Subject: Re: [tip:x86/urgent] x86: mm: Read cr2 before prefetching the
 mmap_lock
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On Tue, 16 Jun 2009, tip-bot for Ingo Molnar wrote:
> 
> It turns out that in current upstream we do exactly that:
> 
> 	prefetchw(&mm->mmap_sem);
> 
> 	/* Get the faulting address: */
> 	address = read_cr2();
> 
> This is not good.

Ack.

		Linus