diff options
| -rw-r--r-- | drivers/usb/gadget/ether.c | 12 |
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); |