diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 46c36ff..a4b14fd 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2171,6 +2171,8 @@
 extern int netdev_class_create_file(struct class_attribute *class_attr);
 extern void netdev_class_remove_file(struct class_attribute *class_attr);
 
+extern struct kobj_ns_type_operations net_ns_type_operations;
+
 extern char *netdev_drivername(const struct net_device *dev, char *buffer, int len);
 
 extern void linkwatch_run_queue(void);