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Date: Mon, 18 Jul 2011 20:20:38 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Hugh Dickins <hughd@google.com>, 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 12:08:04PM -0700, Linus Torvalds wrote:

> But I do agree that it's very unlikely to actually cause problems.
> People just don't move mount points around, and the race would seem to
> be ridiculously hard to ever hit even if you tried to create some
> totally artificial load that does nothing but rename mount-points ;)

vfs_rename() will refuse to move mountpoints.  Required by POSIX, among
other things...

> But I think I'm on the same page with Hugh that at this point none of
> these issues are even remotely recent, they are basically impossible
> to hit, and the fixes are likely potentially more dangerous than the
> bugs they fix, so I'll release 3.0 without them and just apply the
> fixes (and cc stable) afterwards.

Hmm...  Could you pull #for-linus (or #for-linus2, for that matter - same
plus cifs_get_root() fix) first?