1 files changed, 52 insertions, 2 deletions

diff --git a/drivers/net/wireless/virt_wifi.c b/drivers/net/wireless/virt_wifi.c
index be92e1220284..7997cc6de334 100644
--- a/drivers/net/wireless/virt_wifi.c
+++ b/drivers/net/wireless/virt_wifi.c
@@ -548,6 +548,7 @@ static int virt_wifi_newlink(struct net *src_net, struct net_device *dev,
         priv->is_connected = false;
         priv->is_up = false;
         INIT_DELAYED_WORK(&priv->connect, virt_wifi_connect_complete);
+        __module_get(THIS_MODULE);
 
         return 0;
 unregister_netdev:
@@ -578,6 +579,7 @@ static void virt_wifi_dellink(struct net_device *dev,
         netdev_upper_dev_unlink(priv->lowerdev, dev);
 
         unregister_netdevice_queue(dev, head);
+        module_put(THIS_MODULE);
 
         /* Deleting the wiphy is handled in the module destructor. */
 }
@@ -590,6 +592,42 @@ static struct rtnl_link_ops virt_wifi_link_ops = {
         .priv_size      = sizeof(struct virt_wifi_netdev_priv),
 };
 
+static bool netif_is_virt_wifi_dev(const struct net_device *dev)
+{
+        return rcu_access_pointer(dev->rx_handler) == virt_wifi_rx_handler;
+}
+
+static int virt_wifi_event(struct notifier_block *this, unsigned long event,
+                           void *ptr)
+{
+        struct net_device *lower_dev = netdev_notifier_info_to_dev(ptr);
+        struct virt_wifi_netdev_priv *priv;
+        struct net_device *upper_dev;
+        LIST_HEAD(list_kill);
+
+        if (!netif_is_virt_wifi_dev(lower_dev))
+                return NOTIFY_DONE;
+
+        switch (event) {
+        case NETDEV_UNREGISTER:
+                priv = rtnl_dereference(lower_dev->rx_handler_data);
+                if (!priv)
+                        return NOTIFY_DONE;
+
+                upper_dev = priv->upperdev;
+
+                upper_dev->rtnl_link_ops->dellink(upper_dev, &list_kill);
+                unregister_netdevice_many(&list_kill);
+                break;
+        }
+
+        return NOTIFY_DONE;
+}
+
+static struct notifier_block virt_wifi_notifier = {
+        .notifier_call = virt_wifi_event,
+};
+
 /* Acquires and releases the rtnl lock. */
 static int __init virt_wifi_init_module(void)
 {
@@ -598,14 +636,25 @@ static int __init virt_wifi_init_module(void)
         /* Guaranteed to be locallly-administered and not multicast. */
         eth_random_addr(fake_router_bssid);
 
+        err = register_netdevice_notifier(&virt_wifi_notifier);
+        if (err)
+                return err;
+
+        err = -ENOMEM;
         common_wiphy = virt_wifi_make_wiphy();
         if (!common_wiphy)
-                return -ENOMEM;
+                goto notifier;
 
         err = rtnl_link_register(&virt_wifi_link_ops);
         if (err)
-                virt_wifi_destroy_wiphy(common_wiphy);
+                goto destroy_wiphy;
 
+        return 0;
+
+destroy_wiphy:
+        virt_wifi_destroy_wiphy(common_wiphy);
+notifier:
+        unregister_netdevice_notifier(&virt_wifi_notifier);
         return err;
 }
 
@@ -615,6 +664,7 @@ static void __exit virt_wifi_cleanup_module(void)
         /* Will delete any devices that depend on the wiphy. */
         rtnl_link_unregister(&virt_wifi_link_ops);
         virt_wifi_destroy_wiphy(common_wiphy);
+        unregister_netdevice_notifier(&virt_wifi_notifier);
 }
 
 module_init(virt_wifi_init_module);