at76c50x-usb: fix oops on disconnect
flush_workqueue needs to be called instead of the generic one and the
associated functions need to be modified to prevent re-adding
themselves to the workqueue.
The rx_tasklet is also killed in the small (?) chance it is scheduled.
Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Signed-off-by: Kalle Valo <kalle.valo@iki.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/at76c50x-usb.c b/drivers/net/wireless/at76c50x-usb.c
index aa06b90..c79591e 100644
--- a/drivers/net/wireless/at76c50x-usb.c
+++ b/drivers/net/wireless/at76c50x-usb.c
@@ -1848,6 +1848,9 @@
dwork_hw_scan.work);
int ret;
+ if (priv->device_unplugged)
+ return;
+
mutex_lock(&priv->mtx);
ret = at76_get_cmd_status(priv->udev, CMD_SCAN);
@@ -1882,6 +1885,9 @@
at76_dbg(DBG_MAC80211, "%s():", __func__);
+ if (priv->device_unplugged)
+ return 0;
+
mutex_lock(&priv->mtx);
ieee80211_stop_queues(hw);
@@ -1985,6 +1991,10 @@
flags = changed_flags & AT76_SUPPORTED_FILTERS;
*total_flags = AT76_SUPPORTED_FILTERS;
+ /* Bail out after updating flags to prevent a WARN_ON in mac80211. */
+ if (priv->device_unplugged)
+ return;
+
/* FIXME: access to priv->promisc should be protected with
* priv->mtx, but it's impossible because this function needs to be
* atomic */
@@ -2085,8 +2095,7 @@
INIT_WORK(&priv->work_submit_rx, at76_work_submit_rx);
INIT_DELAYED_WORK(&priv->dwork_hw_scan, at76_dwork_hw_scan);
- priv->rx_tasklet.func = at76_rx_tasklet;
- priv->rx_tasklet.data = 0;
+ tasklet_init(&priv->rx_tasklet, at76_rx_tasklet, 0);
priv->pm_mode = AT76_PM_OFF;
priv->pm_period = 0;
@@ -2225,6 +2234,7 @@
priv->scan_min_time = DEF_SCAN_MIN_TIME;
priv->scan_max_time = DEF_SCAN_MAX_TIME;
priv->scan_mode = SCAN_TYPE_ACTIVE;
+ priv->device_unplugged = 0;
/* mac80211 initialisation */
priv->hw->wiphy->max_scan_ssids = 1;
@@ -2266,13 +2276,12 @@
/* The device is gone, don't bother turning it off */
priv->device_unplugged = 1;
- if (priv->mac80211_registered)
+ tasklet_kill(&priv->rx_tasklet);
+
+ if (priv->mac80211_registered) {
+ flush_workqueue(priv->hw->workqueue);
ieee80211_unregister_hw(priv->hw);
-
- /* assuming we used keventd, it must quiesce too */
- flush_scheduled_work();
-
- kfree(priv->bulk_out_buffer);
+ }
if (priv->tx_urb) {
usb_kill_urb(priv->tx_urb);
@@ -2285,6 +2294,8 @@
at76_dbg(DBG_PROC_ENTRY, "%s: unlinked urbs", __func__);
+ kfree(priv->bulk_out_buffer);
+
if (priv->rx_skb)
kfree_skb(priv->rx_skb);