Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

[linux.git] / net / core / dev.c

diff --git a/net/core/dev.c b/net/core/dev.c
index b430f851f3776a98e925ca8579db2ee3b2e39330..22f2640f559a31cfd89dce69fafa20f7d77b0413 100644 (file)
--- 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);