2 files changed, 18 insertions, 4 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index fdcff29df915..f409406254dd 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1184,7 +1184,21 @@ int dev_change_name(struct net_device *dev, const char *newname)
         BUG_ON(!dev_net(dev));
 
         net = dev_net(dev);
-        if (dev->flags & IFF_UP)
+
+        /* Some auto-enslaved devices e.g. failover slaves are
+         * special, as userspace might rename the device after
+         * the interface had been brought up and running since
+         * the point kernel initiated auto-enslavement. Allow
+         * live name change even when these slave devices are
+         * up and running.
+         *
+         * Typically, users of these auto-enslaving devices
+         * don't actually care about slave name change, as
+         * they are supposed to operate on master interface
+         * directly.
+         */
+        if (dev->flags & IFF_UP &&
+            likely(!(dev->priv_flags & IFF_LIVE_RENAME_OK)))
                 return -EBUSY;
 
         write_seqcount_begin(&devnet_rename_seq);
diff --git a/net/core/failover.c b/net/core/failover.c
index 4a92a98ccce9..b5cd3c727285 100644
--- a/net/core/failover.c
+++ b/net/core/failover.c
@@ -80,14 +80,14 @@ static int failover_slave_register(struct net_device *slave_dev)
                 goto err_upper_link;
         }
 
-        slave_dev->priv_flags |= IFF_FAILOVER_SLAVE;
+        slave_dev->priv_flags |= (IFF_FAILOVER_SLAVE | IFF_LIVE_RENAME_OK);
 
         if (fops && fops->slave_register &&
             !fops->slave_register(slave_dev, failover_dev))
                 return NOTIFY_OK;
 
         netdev_upper_dev_unlink(slave_dev, failover_dev);
-        slave_dev->priv_flags &= ~IFF_FAILOVER_SLAVE;
+        slave_dev->priv_flags &= ~(IFF_FAILOVER_SLAVE | IFF_LIVE_RENAME_OK);
 err_upper_link:
         netdev_rx_handler_unregister(slave_dev);
 done:
@@ -121,7 +121,7 @@ int failover_slave_unregister(struct net_device *slave_dev)
 
         netdev_rx_handler_unregister(slave_dev);
         netdev_upper_dev_unlink(slave_dev, failover_dev);
-        slave_dev->priv_flags &= ~IFF_FAILOVER_SLAVE;
+        slave_dev->priv_flags &= ~(IFF_FAILOVER_SLAVE | IFF_LIVE_RENAME_OK);
 
         if (fops && fops->slave_unregister &&
             !fops->slave_unregister(slave_dev, failover_dev))