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Date: Sat, 10 Apr 2010 08:24:02 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Borislav Petkov <bp@alien8.de>
cc: Johannes Weiner <hannes@cmpxchg.org>,
       KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
       Rik van Riel <riel@redhat.com>,
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       Nick Piggin <npiggin@suse.de>, Andrea Arcangeli <aarcange@redhat.com>,
       Hugh Dickins <hugh.dickins@tiscali.co.uk>, sgunderson@bigfoot.com
Subject: Re: [PATCH -v2] rmap: make anon_vma_prepare link in all the anon_vmas
 of a mergeable VMA
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On Sat, 10 Apr 2010, Borislav Petkov wrote:
> > 
> > I will keep running that kernel in the next couple of days and keep you
> > informed in case this is the fix we're gonna use.
> 
> Yep, you jinxed it :)
> 
> This time we got stuck on the anon_vma->lock (yep, we've seen that
> oopsie before). So, it might be that we _really_ are staring at the
> wrong code... Back to square one.

No, I think we're good. I suspect this is a different issue. Do you have 
lockdep enabled, along with mutex and spinlock debugging etc? That might 
help pinpoint what triggers this.

But I think the fact that you are apparently not able to get the list 
corruption is a good sign. Of course, it might just be harder to trigger, 
and these things could all be a sign of a different bug, but my gut feel 
is that we did fix something, and you are just damn good at stressing the 
new code. Kudos.

		Linus