2 files changed, 7 insertions, 22 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index fd992c0f2717..0ae08d3f57e7 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3812,14 +3812,11 @@ static int dev_new_index(struct net *net)
 }
 
 /* Delayed registration/unregisteration */
-static DEFINE_SPINLOCK(net_todo_list_lock);
 static LIST_HEAD(net_todo_list);
 
 static void net_set_todo(struct net_device *dev)
 {
-        spin_lock(&net_todo_list_lock);
         list_add_tail(&dev->todo_list, &net_todo_list);
-        spin_unlock(&net_todo_list_lock);
 }
 
 static void rollback_registered(struct net_device *dev)
@@ -4146,33 +4143,24 @@ static void netdev_wait_allrefs(struct net_device *dev)
  *      free_netdev(y1);
  *      free_netdev(y2);
  *
- * We are invoked by rtnl_unlock() after it drops the semaphore.
+ * We are invoked by rtnl_unlock().
  * This allows us to deal with problems:
  * 1) We can delete sysfs objects which invoke hotplug
  *    without deadlocking with linkwatch via keventd.
  * 2) Since we run with the RTNL semaphore not held, we can sleep
  *    safely in order to wait for the netdev refcnt to drop to zero.
+ *
+ * We must not return until all unregister events added during
+ * the interval the lock was held have been completed.
  */
-static DEFINE_MUTEX(net_todo_run_mutex);
 void netdev_run_todo(void)
 {
         struct list_head list;
 
-        /* Need to guard against multiple cpu's getting out of order. */
-        mutex_lock(&net_todo_run_mutex);
-
-        /* Not safe to do outside the semaphore.  We must not return
-         * until all unregister events invoked by the local processor
-         * have been completed (either by this todo run, or one on
-         * another cpu).
-         */
-        if (list_empty(&net_todo_list))
-                goto out;
-
         /* Snapshot list, allow later requests */
-        spin_lock(&net_todo_list_lock);
         list_replace_init(&net_todo_list, &list);
-        spin_unlock(&net_todo_list_lock);
+
+        __rtnl_unlock();
 
         while (!list_empty(&list)) {
                 struct net_device *dev
@@ -4204,9 +4192,6 @@ void netdev_run_todo(void)
                 /* Free network device */
                 kobject_put(&dev->dev.kobj);
         }
-
-out:
-        mutex_unlock(&net_todo_run_mutex);
 }
 
 static struct net_device_stats *internal_stats(struct net_device *dev)
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 71edb8b36341..d6381c2a4693 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -73,7 +73,7 @@ void __rtnl_unlock(void)
 
 void rtnl_unlock(void)
 {
-        mutex_unlock(&rtnl_mutex);
+        /* This fellow will unlock it for us. */
         netdev_run_todo();
 }