rpms/kernel/F-7 linux-2.6-softmac-deadlock.patch,1.1,1.2

[David Woodhouse (dwmw2)]

Author: dwmw2

Update of /cvs/pkgs/rpms/kernel/F-7
In directory cvs-int.fedora.redhat.com:/tmp/cvs-serv20050

Modified Files:
	linux-2.6-softmac-deadlock.patch 
Log Message:
updated patch

linux-2.6-softmac-deadlock.patch:

Index: linux-2.6-softmac-deadlock.patch
===================================================================
RCS file: /cvs/pkgs/rpms/kernel/F-7/linux-2.6-softmac-deadlock.patch,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- linux-2.6-softmac-deadlock.patch	31 Jul 2007 13:22:29 -0000	1.1
+++ linux-2.6-softmac-deadlock.patch	31 Jul 2007 18:57:04 -0000	1.2
@@ -1,59 +1,53 @@
-From mb at bu3sch.de Tue Jul 31 13:58:04 2007
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-	Jul 2007 14:57:58 +0200
 From: Michael Buesch <mb at bu3sch.de>
-To: David Woodhouse <dwmw2 at infradead.org>
-Subject: [PATCH] softmac: Fix deadlock of wx_set_essid with assoc work
-Date: Tue, 31 Jul 2007 14:57:33 +0200
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-Cc: linux-wireless at vger.kernel.org, John Linville <linville at tuxdriver.com>
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+To: John Linville <linville at tuxdriver.com>
+Subject: [PATCH final] softmac: Fix deadlock of wx_set_essid with assoc work
+Date: Tue, 31 Jul 2007 20:41:04 +0200
 
 The essid wireless extension does deadlock against the assoc mutex,
-as we don't unlock the assoc mutex.
+as we don't unlock the assoc mutex when flushing the workqueue, which
+also holds the lock.
 
 Signed-off-by: Michael Buesch <mb at bu3sch.de>
 
 --
 
-David, please test if this fixes your deadlock.
+David, please stresstest this.
+John, please apply this, if David reports success from his tests.
+John, please notify me when you applied this, so I can immediately
+send it to -stable.
 
 Index: bu3sch-wireless-dev/net/ieee80211/softmac/ieee80211softmac_wx.c
 ===================================================================
---- bu3sch-wireless-dev.orig/net/ieee80211/softmac/ieee80211softmac_wx.c	2007-03-05 18:42:18.000000000 +0100
-+++ bu3sch-wireless-dev/net/ieee80211/softmac/ieee80211softmac_wx.c	2007-07-31 14:51:46.000000000 +0200
-@@ -98,9 +98,12 @@ ieee80211softmac_wx_set_essid(struct net
+--- bu3sch-wireless-dev.orig/net/ieee80211/softmac/ieee80211softmac_wx.c	2007-07-14 18:18:06.000000000 +0200
++++ bu3sch-wireless-dev/net/ieee80211/softmac/ieee80211softmac_wx.c	2007-07-31 20:30:08.000000000 +0200
+@@ -74,8 +74,8 @@ ieee80211softmac_wx_set_essid(struct net
+ 	struct ieee80211softmac_auth_queue_item *authptr;
+ 	int length = 0;
+ 
++check_assoc_again:
+ 	mutex_lock(&sm->associnfo.mutex);
+-
+ 	/* Check if we're already associating to this or another network
+ 	 * If it's another network, cancel and start over with our new network
+ 	 * If it's our network, ignore the change, we're already doing it!
+@@ -98,13 +98,18 @@ ieee80211softmac_wx_set_essid(struct net
  				cancel_delayed_work(&authptr->work);
  			sm->associnfo.bssvalid = 0;
  			sm->associnfo.bssfixed = 0;
 -			flush_scheduled_work();
  			sm->associnfo.associating = 0;
  			sm->associnfo.associated = 0;
-+			/* Unlock mutex, otherwise we deadlock with the assoc work handler. */
++			/* We must unlock to avoid deadlocks with the assoc workqueue
++			 * on the associnfo.mutex */
 +			mutex_unlock(&sm->associnfo.mutex);
 +			flush_scheduled_work();
-+			mutex_lock(&sm->associnfo.mutex);
++			/* Avoid race! Check assoc status again. Maybe someone started an
++			 * association while we flushed. */
++			goto check_assoc_again;
  		}
  	}
  
-
--- 
-Greetings Michael.
+-
+ 	sm->associnfo.static_essid = 0;
+ 	sm->associnfo.assoc_wait = 0;
+