Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
        if (!atomic_inc_not_zero(&hard_iface->refcount))
                goto out;
 
+       /* hard-interface is part of a bridge */
+       if (hard_iface->net_dev->priv_flags & IFF_BRIDGE_PORT)
+               pr_err("You are about to enable batman-adv on '%s' which "
+                      "already is part of a bridge. Unless you know exactly "
+                      "what you are doing this is probably wrong and won't "
+                      "work the way you think it would.\n",
+                      hard_iface->net_dev->name);
+
        soft_iface = dev_get_by_name(&init_net, iface_name);
 
        if (!soft_iface) {