net/af_iucv: always register net_device notifier

Even when running as VM guest (ie pr_iucv != NULL), af_iucv can still
open HiperTransport-based connections. For robust operation these
connections require the af_iucv_netdev_notifier, so register it
unconditionally.

Also handle any error that register_netdevice_notifier() returns.

Fixes: 9fbd87d41392 ("af_iucv: handle netdev events")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 20 insertions, 7 deletions

diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c
index 5264a182d2c3..09e1694b6d34 100644
--- a/net/iucv/af_iucv.c
+++ b/net/iucv/af_iucv.c
@@ -2440,6 +2440,13 @@ out:
         return err;
 }
 
+static void afiucv_iucv_exit(void)
+{
+        device_unregister(af_iucv_dev);
+        driver_unregister(&af_iucv_driver);
+        pr_iucv->iucv_unregister(&af_iucv_handler, 0);
+}
+
 static int __init afiucv_init(void)
 {
         int err;
@@ -2473,11 +2480,18 @@ static int __init afiucv_init(void)
                 err = afiucv_iucv_init();
                 if (err)
                         goto out_sock;
-        } else
-                register_netdevice_notifier(&afiucv_netdev_notifier);
+        }
+
+        err = register_netdevice_notifier(&afiucv_netdev_notifier);
+        if (err)
+                goto out_notifier;
+
         dev_add_pack(&iucv_packet_type);
         return 0;
 
+out_notifier:
+        if (pr_iucv)
+                afiucv_iucv_exit();
 out_sock:
         sock_unregister(PF_IUCV);
 out_proto:
@@ -2491,12 +2505,11 @@ out:
 static void __exit afiucv_exit(void)
 {
         if (pr_iucv) {
-                device_unregister(af_iucv_dev);
-                driver_unregister(&af_iucv_driver);
-                pr_iucv->iucv_unregister(&af_iucv_handler, 0);
+                afiucv_iucv_exit();
                 symbol_put(iucv_if);
-        } else
-                unregister_netdevice_notifier(&afiucv_netdev_notifier);
+        }
+
+        unregister_netdevice_notifier(&afiucv_netdev_notifier);
         dev_remove_pack(&iucv_packet_type);
         sock_unregister(PF_IUCV);
         proto_unregister(&iucv_proto);