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Date: Thu, 11 Nov 2010 16:48:45 -0800
From: Ben Greear <greearb@candelatech.com>
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To: Tejun Heo <tj@kernel.org>
CC: Johannes Berg <johannes@sipsolutions.net>,
	"linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>
Subject: Re: ath5k/mac80211:  Reproducible deadlock with 64-stations.
References: <4CDB2488.4040802@candelatech.com> <1289437356.3748.25.camel@jlt3.sipsolutions.net> <4CDBB716.7020802@kernel.org> <4CDC2016.8020200@candelatech.com>
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I have a potential scenario:

The ieee80211_do_stop logic is called under RTNL, and it
then calls flush_work().

What if the worker thread is currently blocked on something like
wireless_nlevent_process which tries to acquire rtnl?

Wouldn't that cause a deadlock?

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com