From f30e0f8d19604b75ceaf6b4b220d13a768019551 Mon Sep 17 00:00:00 2001
From: Benedikt Spranger <bene@linutronix.de>
Date: Tue, 2 Oct 2007 14:40:48 -0700
Subject: [PATCH] --- yaml --- r: 67911 b: refs/heads/master c:
 5395353e0c8272fe73ac914acd7e4add0da2bef0 h: refs/heads/master i:   67909:
 1fbe6c9982590a499d0ad793e96e3a19163c28d0   67907:
 59ea39a102ddcf914d0a303172e6230fe6ddc221   67903:
 077b1102aecafa4651f6bbd253fe8c54a23852d6 v: v3

---
 [refs]                           |  2 +-
 trunk/drivers/usb/gadget/ether.c | 12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 4ef7e82a283d..a0547ddd9961 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9dcfbd97a695a3c28a867501127fa35ac49bc805
+refs/heads/master: 5395353e0c8272fe73ac914acd7e4add0da2bef0
diff --git a/trunk/drivers/usb/gadget/ether.c b/trunk/drivers/usb/gadget/ether.c
index ff244f42723f..9f4fd7e849a0 100644
--- a/trunk/drivers/usb/gadget/ether.c
+++ b/trunk/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);