summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--drivers/usb/gadget/ether.c12
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/usb/gadget/ether.c b/drivers/usb/gadget/ether.c
index ff244f42723..9f4fd7e849a 100644
--- a/drivers/usb/gadget/ether.c
+++ b/drivers/usb/gadget/ether.c
@@ -1957,8 +1957,20 @@ static int eth_start_xmit (struct sk_buff *skb, struct net_device *net)
}
spin_lock_irqsave(&dev->req_lock, flags);
+ /*
+ * this freelist can be empty if an interrupt triggered disconnect()
+ * and reconfigured the gadget (shutting down this queue) after the
+ * network stack decided to xmit but before we got the spinlock.
+ */
+ if (list_empty(&dev->tx_reqs)) {
+ spin_unlock_irqrestore(&dev->req_lock, flags);
+ return 1;
+ }
+
req = container_of (dev->tx_reqs.next, struct usb_request, list);
list_del (&req->list);
+
+ /* temporarily stop TX queue when the freelist empties */
if (list_empty (&dev->tx_reqs))
netif_stop_queue (net);
spin_unlock_irqrestore(&dev->req_lock, flags);