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Date: Sat, 28 May 2011 17:43:27 -0700 (PDT)
From: Hugh Dickins <hughd@google.com>
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To: Linus Torvalds <torvalds@linux-foundation.org>
cc: Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Andrew Morton <akpm@linux-foundation.org>,
        Rik van Riel <riel@redhat.com>, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Subject: Re: [PATCH] mm: fix page_lock_anon_vma leaving mutex locked
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On Sat, 28 May 2011, Linus Torvalds wrote:
> On Sat, May 28, 2011 at 5:12 PM, Hugh Dickins <hughd@google.com> wrote:
> >
> > Though I think I'm arriving at the conclusion that this patch
> > is correct as is, despite the doubts that have arisen.
> 
> Well, you hopefully saw my second email where I had come to the same conclusion.

Yes, thanks.

> 
> So I applied the third patch as well, after all. I think it's at the
> very least at least "more correct" than what we have now. Whether that
> "page_mapped()" should then be extended to do something else is an
> additional thing, and I suspect it would affect the slow-path case
> too.

Yes, I agree it's certainly more correct (two machines running well
with it for 33 hours now, one of them would hang in 7 or 17 hours).

And I'm increasingly confident that it's complete too, but it will be
interesting to see whether I've persuaded Peter.  It was certainly a
very good point that he raised, that I hadn't thought of at all.

Hugh