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Subject: Re: [PATCH V2] jffs2: Fix lock acquisition order bug in gc path
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Josh Cartwright <joshc@linux.com>, Joakim Tjernlund
 <Joakim.Tjernlund@transmode.se>
Date: Fri, 13 Apr 2012 18:14:00 +0300
In-Reply-To: <20120329233453.GA23698@joshcartwright.net>
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Cc: linux-mtd@lists.infradead.org, Brian Norris <computersforpeace@gmail.com>,
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On Thu, 2012-03-29 at 19:34 -0400, Josh Cartwright wrote:
> The locking policy is such that the erase_complete_block spinlock is
> nested within the alloc_sem mutex.  This fixes a case in which the
> acquisition order was erroneously reversed.  This issue was caught by
> the following lockdep splat:

I've added the follwing:

This was introduce in '81cfc9f jffs2: Fix serious write stall due to
erase'.
   =20
Cc: stable@kernel.org [2.6.37+]

and pushed to l2-mtd.git, thanks! CC-in Joakim to let him know that his
patch has a bug and that he might want this fix in his system(s) as
well.

--=20
Best Regards,
Artem Bityutskiy

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