diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index d3d2306..13bbbde 100644
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -110,6 +110,7 @@
 					       __be16 vlan_proto, u16 vlan_id);
 extern struct net_device *vlan_dev_real_dev(const struct net_device *dev);
 extern u16 vlan_dev_vlan_id(const struct net_device *dev);
+extern __be16 vlan_dev_vlan_proto(const struct net_device *dev);
 
 /**
  *	struct vlan_priority_tci_mapping - vlan egress priority mappings
@@ -216,6 +217,12 @@
 	return 0;
 }
 
+static inline __be16 vlan_dev_vlan_proto(const struct net_device *dev)
+{
+	BUG();
+	return 0;
+}
+
 static inline u16 vlan_dev_get_egress_qos_mask(struct net_device *dev,
 					       u32 skprio)
 {