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Date: Tue, 19 Jul 2011 00:17:38 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Nick Piggin <npiggin@kernel.dk>, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] vfs: fix race in rcu lookup of pruned dentry
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On Mon, Jul 18, 2011 at 03:43:29PM -0700, Hugh Dickins wrote:
> Yes, that looks like THE right fix to me, making others irrelevant.
> But I haven't tested it either, won't begin to do so until tonight.
> And I fear I won't notice if there's any silly little bug in there,
> which forces every fast RCU lookup to go the slow way instead!
> 
> Inlined for the benefit of wider scrutiny:

Looks sane.  Applied.  I'll wait with pull request until you test it,
but that looks right.