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Subject: Re: [PATCH] mac80211:  Fix deadlock in ieee80211_do_stop.
From: Johannes Berg <johannes@sipsolutions.net>
To: Tejun Heo <tj@kernel.org>
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Date: Wed, 17 Nov 2010 10:53:25 -0800
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On Wed, 2010-11-17 at 09:47 +0100, Tejun Heo wrote:

> WQ_NON_REENTRANT doesn't guarantee ordered execution but it guarantees
> that a single work is not executed concurrently on multiple CPUs.  I'm
> not sure whether this would be safe for the workqueue used by mac80211
> but it should let us know whether the workqueue is choked due to a
> work which is executing for long time.  In the long run, if using non
> reentrant is safe for mac80211, using it would be much better.

No, I don't think it's safe for mac80211.

johannes