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	Wed, 4 Jul 2007 09:59:20 -0400
Subject: Re: [RFC/PATCH] debug workqueue deadlocks with lockdep
From: Johannes Berg <johannes@sipsolutions.net>
To: Ingo Molnar <mingo@elte.hu>
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Date: Wed, 04 Jul 2007 15:59:54 +0200
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On Wed, 2007-07-04 at 14:21 +0200, Ingo Molnar wrote:

> well, in this case the lock/unlock should nest perfectly (i.e. it should=20
> always be balanced perfectly), so indeed calling with nested=3D=3D1 leads=
 to=20
> stricter checking.
>=20
> non-nested unlocks occur when people do stuff like:
>=20
> 	spin_lock(&lock1);
> 	spin_lock(&lock2);
> 	spin_unlock(&lock1);
> 	spin_unlock(&lock2);
>=20
> the first unlock is not 'nested perfectly'. Now for the workqueue=20
> dep_map this shouldnt be a legal combination, right?

I don't think so, will change to use nested=3D=3D1.

johannes

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