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Subject: Re: [PATCH 2/2] drivers/mtd/ubi: Eliminate update of
	list_for_each_entry loop cursor
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Julia Lawall <julia@diku.dk>
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Date: Tue, 24 Aug 2010 15:52:12 +0300
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	David Woodhouse <dwmw2@infradead.org>, linux-kernel@vger.kernel.org
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On Sat, 2010-08-07 at 11:09 +0200, Julia Lawall wrote:
> From: Julia Lawall <julia@diku.dk>
> 
> list_for_each_entry uses its first argument to move from one element to the
> next, so modifying it can break the iteration.  The variable re1 is already
> used within the loop as a temporary variable, and is not live here.
> 
> The semantic match that finds this problem is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @r@
> iterator name list_for_each_entry;
> expression x,E;
> position p1,p2;
> @@
> 
> list_for_each_entry@p1(x,...) { <... x =@p2 E ...> }
> 
> @@
> expression x,E;
> position r.p1,r.p2;
> statement S;
> @@
> 
> *x =@p2 E
> ...
> list_for_each_entry@p1(x,...) S
> // </smpl>
> 
> Signed-off-by: Julia Lawall <julia@diku.dk>

Pushed to ubi-2.6.git tree. This won't be seen in linux-next for some
time though, but I'll make it visible in linux-next at some point soon.

Thanks!

-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)