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Message-ID: <1383735487.14307.29.camel@jlt4.sipsolutions.net> (sfid-20131106_115814_251610_D4434F58)
Subject: Re: [PATCH] mac80211: fix scheduled scan rtnl deadlock
From: Johannes Berg <johannes@sipsolutions.net>
To: linux-wireless@vger.kernel.org
Cc: Eliad Peller <eliadx.peller@intel.com>
Date: Wed, 06 Nov 2013 11:58:07 +0100
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On Wed, 2013-11-06 at 10:43 +0100, Johannes Berg wrote:
> From: Johannes Berg <johannes.berg@intel.com>
> 
> When changing cfg80211 to use RTNL locking, this caused a
> deadlock in mac80211 as it calls cfg80211_sched_scan_stopped()
> from a work item that's on a workqueue that is flushed with
> the RTNL held.
> 
> Fix this by simply using schedule_work(), the work only needs
> to finish running before the wiphy is unregistered, no other
> synchronisation (e.g. with suspend) is really required since
> for suspend userspace is already blocked anyway when we flush
> the workqueue so will only pick up the event after resume.

Applied.

johannes