3 files changed, 32 insertions, 12 deletions

diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index dcad3100b164..074e4a69a728 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -1058,7 +1058,7 @@ static int dsa_tree_setup_switches(struct dsa_switch_tree *dst)
 static int dsa_tree_setup_master(struct dsa_switch_tree *dst)
 {
 	struct dsa_port *dp;
-	int err;
+	int err = 0;
 
 	rtnl_lock();
 
@@ -1066,13 +1066,13 @@ static int dsa_tree_setup_master(struct dsa_switch_tree *dst)
 		if (dsa_port_is_cpu(dp)) {
 			err = dsa_master_setup(dp->master, dp);
 			if (err)
-				return err;
+				break;
 		}
 	}
 
 	rtnl_unlock();
 
-	return 0;
+	return err;
 }
 
 static void dsa_tree_teardown_master(struct dsa_switch_tree *dst)
@@ -1261,7 +1261,7 @@ int dsa_tree_change_tag_proto(struct dsa_switch_tree *dst,
 	info.tag_ops = tag_ops;
 	err = dsa_tree_notify(dst, DSA_NOTIFIER_TAG_PROTO, &info);
 	if (err)
-		return err;
+		goto out_unwind_tagger;
 
 	err = dsa_tree_bind_tag_proto(dst, tag_ops);
 	if (err)
diff --git a/net/dsa/master.c b/net/dsa/master.c
index 2199104ca7df..880f910b23a9 100644
--- a/net/dsa/master.c
+++ b/net/dsa/master.c
@@ -260,11 +260,16 @@ static void dsa_netdev_ops_set(struct net_device *dev,
 	dev->dsa_ptr->netdev_ops = ops;
 }
 
+/* Keep the master always promiscuous if the tagging protocol requires that
+ * (garbles MAC DA) or if it doesn't support unicast filtering, case in which
+ * it would revert to promiscuous mode as soon as we call dev_uc_add() on it
+ * anyway.
+ */
 static void dsa_master_set_promiscuity(struct net_device *dev, int inc)
 {
 	const struct dsa_device_ops *ops = dev->dsa_ptr->tag_ops;
 
-	if (!ops->promisc_on_master)
+	if ((dev->priv_flags & IFF_UNICAST_FLT) && !ops->promisc_on_master)
 		return;
 
 	ASSERT_RTNL();
diff --git a/net/dsa/port.c b/net/dsa/port.c
index bd78192e0e47..1a40c52f5a42 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -395,10 +395,17 @@ void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br)
 		.tree_index = dp->ds->dst->index,
 		.sw_index = dp->ds->index,
 		.port = dp->index,
-		.bridge = *dp->bridge,
 	};
 	int err;
 
+	/* If the port could not be offloaded to begin with, then
+	 * there is nothing to do.
+	 */
+	if (!dp->bridge)
+		return;
+
+	info.bridge = *dp->bridge;
+
 	/* Here the port is already unbridged. Reflect the current configuration
 	 * so that drivers can program their chips accordingly.
 	 */
@@ -781,9 +788,15 @@ int dsa_port_host_fdb_add(struct dsa_port *dp, const unsigned char *addr,
 	struct dsa_port *cpu_dp = dp->cpu_dp;
 	int err;
 
-	err = dev_uc_add(cpu_dp->master, addr);
-	if (err)
-		return err;
+	/* Avoid a call to __dev_set_promiscuity() on the master, which
+	 * requires rtnl_lock(), since we can't guarantee that is held here,
+	 * and we can't take it either.
+	 */
+	if (cpu_dp->master->priv_flags & IFF_UNICAST_FLT) {
+		err = dev_uc_add(cpu_dp->master, addr);
+		if (err)
+			return err;
+	}
 
 	return dsa_port_notify(dp, DSA_NOTIFIER_HOST_FDB_ADD, &info);
 }
@@ -800,9 +813,11 @@ int dsa_port_host_fdb_del(struct dsa_port *dp, const unsigned char *addr,
 	struct dsa_port *cpu_dp = dp->cpu_dp;
 	int err;
 
-	err = dev_uc_del(cpu_dp->master, addr);
-	if (err)
-		return err;
+	if (cpu_dp->master->priv_flags & IFF_UNICAST_FLT) {
+		err = dev_uc_del(cpu_dp->master, addr);
+		if (err)
+			return err;
+	}
 
 	return dsa_port_notify(dp, DSA_NOTIFIER_HOST_FDB_DEL, &info);
 }