3 files changed, 12 insertions, 0 deletions

diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index 0ef0eb0db945..0fc9dc7f20db 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -788,6 +788,10 @@ static int macvlan_device_event(struct notifier_block *unused,
                 }
                 break;
         case NETDEV_UNREGISTER:
+                /* twiddle thumbs on netns device moves */
+                if (dev->reg_state != NETREG_UNREGISTERING)
+                        break;
+
                 list_for_each_entry_safe(vlan, next, &port->vlans, list)
                         vlan->dev->rtnl_link_ops->dellink(vlan->dev, NULL);
                 break;
diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c
index a2ad15250575..2c6c2bd6e4a9 100644
--- a/net/8021q/vlan.c
+++ b/net/8021q/vlan.c
@@ -525,6 +525,10 @@ static int vlan_device_event(struct notifier_block *unused, unsigned long event,
                 break;
 
         case NETDEV_UNREGISTER:
+                /* twiddle thumbs on netns device moves */
+                if (dev->reg_state != NETREG_UNREGISTERING)
+                        break;
+
                 /* Delete all VLANs for this dev. */
                 grp->killall = 1;
 
diff --git a/net/core/dev.c b/net/core/dev.c
index c09ff096525a..2c7934f8cf3e 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5686,6 +5686,10 @@ int dev_change_net_namespace(struct net_device *dev, struct net *net, const char
 
         /* Notify protocols, that we are about to destroy
            this device. They should clean all the things.
+
+           Note that dev->reg_state stays at NETREG_REGISTERED.
+           This is wanted because this way 8021q and macvlan know
+           the device is just moving and can keep their slaves up.
         */
         call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
         call_netdevice_notifiers(NETDEV_UNREGISTER_BATCH, dev);