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Subject: Re: [PATCH] list_head debugging?
From: Robert Love <rml@tech9.net>
To: Zach Brown <zab@zabbo.net>
Cc: linux-kernel@vger.kernel.org
In-Reply-To: <20020920165304.A4588@bitchcake.off.net>
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Date: 20 Sep 2002 17:34:36 -0400
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On Fri, 2002-09-20 at 16:53, Zach Brown wrote:

> A friend recently was bitten by passing a list_head from list_for_each
> to a code path that later moved the list_head around.  Does the attached
> patch re-create some debugging wheel that's hiding off in a corner
> somewhere?
> 
> Beyond catching the obvious use of uninitialized things, it also seems
> to catch double adds, double deletes, and simple deletes of 'pos' in
> list_for_each.  it even seems to bark about the seemingly hard-to-detect
> movement of 'pos' from the iterating list to another, but probably only
> in the rare case where you're unconditionally moving all 'pos' in the
> loop body.  (you eventually iterate into the second list's head and try
> to add it to itself)

Hey, cool!

Yes, I think a lot of people would be all for something like this as a
CONFIG_DEBUG_LISTS or such.  Very nice.

	Robert Love

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