libertas: clear current command on card removal

If certain commands were in-flight when the card was pulled or the
driver rmmod-ed, cleanup would block on the work queue stopping, but the
work queue was in turn blocked on the current command being canceled,
which didn't happen.  Fix that.

Signed-off-by: Dan Williams <dcbw@redhat.com>
Cc: stable <stable@kernel.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 19 insertions, 1 deletions

diff --git a/drivers/net/wireless/libertas/main.c b/drivers/net/wireless/libertas/main.c
index 2436634b6b7e..73dc8c72402a 100644
--- a/drivers/net/wireless/libertas/main.c
+++ b/drivers/net/wireless/libertas/main.c
@@ -1205,7 +1205,13 @@ void lbs_remove_card(struct lbs_private *priv)
         cancel_delayed_work_sync(&priv->scan_work);
         cancel_delayed_work_sync(&priv->assoc_work);
         cancel_work_sync(&priv->mcast_work);
+
+        /* worker thread destruction blocks on the in-flight command which
+         * should have been cleared already in lbs_stop_card().
+         */
+        lbs_deb_main("destroying worker thread\n");
         destroy_workqueue(priv->work_thread);
+        lbs_deb_main("done destroying worker thread\n");
 
         if (priv->psmode == LBS802_11POWERMODEMAX_PSP) {
                 priv->psmode = LBS802_11POWERMODECAM;
@@ -1323,14 +1329,26 @@ void lbs_stop_card(struct lbs_private *priv)
                 device_remove_file(&dev->dev, &dev_attr_lbs_rtap);
         }
 
-        /* Flush pending command nodes */
+        /* Delete the timeout of the currently processing command */
         del_timer_sync(&priv->command_timer);
+
+        /* Flush pending command nodes */
         spin_lock_irqsave(&priv->driver_lock, flags);
+        lbs_deb_main("clearing pending commands\n");
         list_for_each_entry(cmdnode, &priv->cmdpendingq, list) {
                 cmdnode->result = -ENOENT;
                 cmdnode->cmdwaitqwoken = 1;
                 wake_up_interruptible(&cmdnode->cmdwait_q);
         }
+
+        /* Flush the command the card is currently processing */
+        if (priv->cur_cmd) {
+                lbs_deb_main("clearing current command\n");
+                priv->cur_cmd->result = -ENOENT;
+                priv->cur_cmd->cmdwaitqwoken = 1;
+                wake_up_interruptible(&priv->cur_cmd->cmdwait_q);
+        }
+        lbs_deb_main("done clearing commands\n");
         spin_unlock_irqrestore(&priv->driver_lock, flags);
 
         unregister_netdev(dev);