Subject: [PATCH net-next-2.6] veth: Fix unregister_netdevice_queue for veth

From: [email-masked] (Eric W. Biederman)
Date: Fri, 30 Oct 2009 17:51:13 -0700

I tested the recent unregister many changes and got a weird,
nasty and seemingly unrelasted kernel oops. Changing
unregister_netdevice_queue to use list_move_tail fixes
the problem for me.

ip link add type veth
rmmod veth

ls /sys/class/net/
showed one of the veth devices still present.

A subsequent ip link oopsed the box.

Signed-off-by: "Eric W. Biederman" <[email-masked]>

---
diff --git a/net/core/dev.c b/net/core/dev.c
index 94f42a1..9c0b202 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5227,6 +5227,7 @@ struct net_device *alloc_netdev_mq(int sizeof_priv, const char *name,
 	netdev_init_queues(dev);
 
 	INIT_LIST_HEAD(&dev->napi_list);
+	INIT_LIST_HEAD(&dev->unreg_list);
 	dev->priv_flags = IFF_XMIT_DST_RELEASE;
 	setup(dev);
 	strcpy(dev->name, name);
@@ -5308,7 +5309,7 @@ void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
 	ASSERT_RTNL();
 
 	if (head) {
-		list_add_tail(&dev->unreg_list, head);
+		list_move_tail(&dev->unreg_list, head);
 	} else {
 		rollback_registered(dev);
 		/* Finish processing unregister after unlock */