diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index 543d2c3e0f0d623a187a9aacfc4ef081a9d989e4..9f673cdfecf8d32a0385caf218baa2f37f76e148 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -863,6 +863,7 @@ static int batadv_softif_init_late(struct net_device *dev)
  * batadv_softif_slave_add - Add a slave interface to a batadv_soft_interface
  * @dev: batadv_soft_interface used as master interface
  * @slave_dev: net_device which should become the slave interface
+ * @extack: extended ACK report struct
  *
  * Return: 0 if successful or error otherwise.
  */