at76c50x-usb: avoid mutex deadlock in at76_dwork_hw_scan
authorJohn W. Linville <linville@tuxdriver.com>
Thu, 28 May 2009 09:39:02 +0000 (11:39 +0200)
committerJohn W. Linville <linville@tuxdriver.com>
Fri, 29 May 2009 10:41:01 +0000 (12:41 +0200)
http://bugzilla.kernel.org/show_bug.cgi?id=13312

at76_dwork_hw_scan holds a mutex while calling ieee80211_scan_completed,
which then calls at76_config which needs the same mutex.  This reworks
the ordering to not hold the lock while calling ieee80211_scan_completed.

Signed-off-by: John W. Linville <linville@tuxdriver.com>
drivers/net/wireless/at76c50x-usb.c

index 744f4f4dd3d17c64dae7193bfd2122794fb94ae4..8d93ca4651b9fad66e2cd7c890aa757cf0c27d2e 100644 (file)
@@ -1873,18 +1873,18 @@ static void at76_dwork_hw_scan(struct work_struct *work)
        if (ret != CMD_STATUS_COMPLETE) {
                queue_delayed_work(priv->hw->workqueue, &priv->dwork_hw_scan,
                                   SCAN_POLL_INTERVAL);
-               goto exit;
+               mutex_unlock(&priv->mtx);
+               return;
        }
 
-       ieee80211_scan_completed(priv->hw, false);
-
        if (is_valid_ether_addr(priv->bssid))
                at76_join(priv);
 
-       ieee80211_wake_queues(priv->hw);
-
-exit:
        mutex_unlock(&priv->mtx);
+
+       ieee80211_scan_completed(priv->hw, false);
+
+       ieee80211_wake_queues(priv->hw);
 }
 
 static int at76_hw_scan(struct ieee80211_hw *hw,