From: John W. Linville Date: Thu, 28 May 2009 09:39:02 +0000 (+0200) Subject: at76c50x-usb: avoid mutex deadlock in at76_dwork_hw_scan X-Git-Tag: v2.6.30-rc8~4^2~9^2~1 X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=commitdiff_plain;h=21a4cc00e8e67edcfc1bdb9af6d370ed1226eb86 at76c50x-usb: avoid mutex deadlock in at76_dwork_hw_scan 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 --- diff --git a/drivers/net/wireless/at76c50x-usb.c b/drivers/net/wireless/at76c50x-usb.c index 744f4f4..8d93ca4 100644 --- a/drivers/net/wireless/at76c50x-usb.c +++ b/drivers/net/wireless/at76c50x-usb.c @@ -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,