diff --git a/Documentation/devicetree/bindings/net/dsa/dsa.txt b/Documentation/devicetree/bindings/net/dsa/dsa.txt
index e124847..f0b4cd7 100644
--- a/Documentation/devicetree/bindings/net/dsa/dsa.txt
+++ b/Documentation/devicetree/bindings/net/dsa/dsa.txt
@@ -19,7 +19,9 @@
 (DSA_MAX_SWITCHES).
 Each of these switch child nodes should have the following required properties:
 
-- reg			: Describes the switch address on the MII bus
+- reg			: Contains two fields. The first one describes the
+			  address on the MII bus. The second is the switch
+			  number that must be unique in cascaded configurations
 - #address-cells	: Must be 1
 - #size-cells		: Must be 0
 
diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index 96208f1..2db6532 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -2658,16 +2658,11 @@
 static int mvneta_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 {
 	struct mvneta_port *pp = netdev_priv(dev);
-	int ret;
 
 	if (!pp->phy_dev)
 		return -ENOTSUPP;
 
-	ret = phy_mii_ioctl(pp->phy_dev, ifr, cmd);
-	if (!ret)
-		mvneta_adjust_link(dev);
-
-	return ret;
+	return phy_mii_ioctl(pp->phy_dev, ifr, cmd);
 }
 
 /* Ethtool methods */
diff --git a/drivers/net/ethernet/mellanox/mlx4/cmd.c b/drivers/net/ethernet/mellanox/mlx4/cmd.c
index 3350721..546ca42 100644
--- a/drivers/net/ethernet/mellanox/mlx4/cmd.c
+++ b/drivers/net/ethernet/mellanox/mlx4/cmd.c
@@ -724,7 +724,8 @@
 		 * on the host, we deprecate the error message for this
 		 * specific command/input_mod/opcode_mod/fw-status to be debug.
 		 */
-		if (op == MLX4_CMD_SET_PORT && in_modifier == 1 &&
+		if (op == MLX4_CMD_SET_PORT &&
+		    (in_modifier == 1 || in_modifier == 2) &&
 		    op_modifier == 0 && context->fw_status == CMD_STAT_BAD_SIZE)
 			mlx4_dbg(dev, "command 0x%x failed: fw status = 0x%x\n",
 				 op, context->fw_status);
diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index e9b960f..720aaf6 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -1008,8 +1008,7 @@
 
 static int xennet_change_mtu(struct net_device *dev, int mtu)
 {
-	int max = xennet_can_sg(dev) ?
-		XEN_NETIF_MAX_TX_SIZE - MAX_TCP_HEADER : ETH_DATA_LEN;
+	int max = xennet_can_sg(dev) ? XEN_NETIF_MAX_TX_SIZE : ETH_DATA_LEN;
 
 	if (mtu > max)
 		return -EINVAL;
@@ -1279,8 +1278,6 @@
 	netdev->ethtool_ops = &xennet_ethtool_ops;
 	SET_NETDEV_DEV(netdev, &dev->dev);
 
-	netif_set_gso_max_size(netdev, XEN_NETIF_MAX_TX_SIZE - MAX_TCP_HEADER);
-
 	np->netdev = netdev;
 
 	netif_carrier_off(netdev);
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index dcf6ec2..2787388 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2185,6 +2185,12 @@
 void synchronize_net(void);
 int init_dummy_netdev(struct net_device *dev);
 
+DECLARE_PER_CPU(int, xmit_recursion);
+static inline int dev_recursion_level(void)
+{
+	return this_cpu_read(xmit_recursion);
+}
+
 struct net_device *dev_get_by_index(struct net *net, int ifindex);
 struct net_device *__dev_get_by_index(struct net *net, int ifindex);
 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex);
diff --git a/include/net/ip.h b/include/net/ip.h
index 025c61c..6cc1eaf 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -453,22 +453,6 @@
 
 #endif
 
-static inline int sk_mc_loop(struct sock *sk)
-{
-	if (!sk)
-		return 1;
-	switch (sk->sk_family) {
-	case AF_INET:
-		return inet_sk(sk)->mc_loop;
-#if IS_ENABLED(CONFIG_IPV6)
-	case AF_INET6:
-		return inet6_sk(sk)->mc_loop;
-#endif
-	}
-	WARN_ON(1);
-	return 1;
-}
-
 bool ip_call_ra_chain(struct sk_buff *skb);
 
 /*
diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h
index 1d09b46..eda131d 100644
--- a/include/net/ip6_route.h
+++ b/include/net/ip6_route.h
@@ -174,7 +174,8 @@
 
 static inline int ip6_skb_dst_mtu(struct sk_buff *skb)
 {
-	struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
+	struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
+				inet6_sk(skb->sk) : NULL;
 
 	return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ?
 	       skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb));
diff --git a/include/net/sock.h b/include/net/sock.h
index ab186b1..e4079c2 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1762,6 +1762,8 @@
 
 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
 
+bool sk_mc_loop(struct sock *sk);
+
 static inline bool sk_can_gso(const struct sock *sk)
 {
 	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
diff --git a/net/core/dev.c b/net/core/dev.c
index 962ee9d..45109b7 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2848,7 +2848,9 @@
 #define skb_update_prio(skb)
 #endif
 
-static DEFINE_PER_CPU(int, xmit_recursion);
+DEFINE_PER_CPU(int, xmit_recursion);
+EXPORT_SYMBOL(xmit_recursion);
+
 #define RECURSION_LIMIT 10
 
 /**
diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c
index 44706e8..e4fdc9d 100644
--- a/net/core/fib_rules.c
+++ b/net/core/fib_rules.c
@@ -175,9 +175,9 @@
 
 	spin_lock(&net->rules_mod_lock);
 	list_del_rcu(&ops->list);
-	fib_rules_cleanup_ops(ops);
 	spin_unlock(&net->rules_mod_lock);
 
+	fib_rules_cleanup_ops(ops);
 	call_rcu(&ops->rcu, fib_rules_put_rcu);
 }
 EXPORT_SYMBOL_GPL(fib_rules_unregister);
diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index 5221f97..70d3450 100644
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -198,8 +198,10 @@
  */
 int peernet2id(struct net *net, struct net *peer)
 {
-	int id = __peernet2id(net, peer, true);
+	bool alloc = atomic_read(&peer->count) == 0 ? false : true;
+	int id;
 
+	id = __peernet2id(net, peer, alloc);
 	return id >= 0 ? id : NETNSA_NSID_NOT_ASSIGNED;
 }
 EXPORT_SYMBOL(peernet2id);
@@ -349,7 +351,7 @@
 static void cleanup_net(struct work_struct *work)
 {
 	const struct pernet_operations *ops;
-	struct net *net, *tmp, *peer;
+	struct net *net, *tmp;
 	struct list_head net_kill_list;
 	LIST_HEAD(net_exit_list);
 
@@ -365,6 +367,14 @@
 	list_for_each_entry(net, &net_kill_list, cleanup_list) {
 		list_del_rcu(&net->list);
 		list_add_tail(&net->exit_list, &net_exit_list);
+		for_each_net(tmp) {
+			int id = __peernet2id(tmp, net, false);
+
+			if (id >= 0)
+				idr_remove(&tmp->netns_ids, id);
+		}
+		idr_destroy(&net->netns_ids);
+
 	}
 	rtnl_unlock();
 
@@ -390,26 +400,12 @@
 	 */
 	rcu_barrier();
 
-	rtnl_lock();
 	/* Finally it is safe to free my network namespace structure */
 	list_for_each_entry_safe(net, tmp, &net_exit_list, exit_list) {
-		/* Unreference net from all peers (no need to loop over
-		 * net_exit_list because idr_destroy() will be called for each
-		 * element of this list.
-		 */
-		for_each_net(peer) {
-			int id = __peernet2id(peer, net, false);
-
-			if (id >= 0)
-				idr_remove(&peer->netns_ids, id);
-		}
-		idr_destroy(&net->netns_ids);
-
 		list_del_init(&net->exit_list);
 		put_user_ns(net->user_ns);
 		net_drop_ns(net);
 	}
-	rtnl_unlock();
 }
 static DECLARE_WORK(net_cleanup_work, cleanup_net);
 
diff --git a/net/core/sock.c b/net/core/sock.c
index 78e89eb..71e3e5f 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -653,6 +653,25 @@
 		sock_reset_flag(sk, bit);
 }
 
+bool sk_mc_loop(struct sock *sk)
+{
+	if (dev_recursion_level())
+		return false;
+	if (!sk)
+		return true;
+	switch (sk->sk_family) {
+	case AF_INET:
+		return inet_sk(sk)->mc_loop;
+#if IS_ENABLED(CONFIG_IPV6)
+	case AF_INET6:
+		return inet6_sk(sk)->mc_loop;
+#endif
+	}
+	WARN_ON(1);
+	return true;
+}
+EXPORT_SYMBOL(sk_mc_loop);
+
 /*
  *	This is meant for all protocols to use and covers goings on
  *	at the socket level. Everything here is generic.
diff --git a/net/decnet/dn_rules.c b/net/decnet/dn_rules.c
index faf7cc3..9d66a0f 100644
--- a/net/decnet/dn_rules.c
+++ b/net/decnet/dn_rules.c
@@ -248,7 +248,9 @@
 
 void __exit dn_fib_rules_cleanup(void)
 {
+	rtnl_lock();
 	fib_rules_unregister(dn_fib_rules_ops);
+	rtnl_unlock();
 	rcu_barrier();
 }
 
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 2173402..4dea2e0 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -501,12 +501,10 @@
 #ifdef CONFIG_OF
 static int dsa_of_setup_routing_table(struct dsa_platform_data *pd,
 					struct dsa_chip_data *cd,
-					int chip_index,
+					int chip_index, int port_index,
 					struct device_node *link)
 {
-	int ret;
 	const __be32 *reg;
-	int link_port_addr;
 	int link_sw_addr;
 	struct device_node *parent_sw;
 	int len;
@@ -519,6 +517,10 @@
 	if (!reg || (len != sizeof(*reg) * 2))
 		return -EINVAL;
 
+	/*
+	 * Get the destination switch number from the second field of its 'reg'
+	 * property, i.e. for "reg = <0x19 1>" sw_addr is '1'.
+	 */
 	link_sw_addr = be32_to_cpup(reg + 1);
 
 	if (link_sw_addr >= pd->nr_chips)
@@ -535,20 +537,9 @@
 		memset(cd->rtable, -1, pd->nr_chips * sizeof(s8));
 	}
 
-	reg = of_get_property(link, "reg", NULL);
-	if (!reg) {
-		ret = -EINVAL;
-		goto out;
-	}
-
-	link_port_addr = be32_to_cpup(reg);
-
-	cd->rtable[link_sw_addr] = link_port_addr;
+	cd->rtable[link_sw_addr] = port_index;
 
 	return 0;
-out:
-	kfree(cd->rtable);
-	return ret;
 }
 
 static void dsa_of_free_platform_data(struct dsa_platform_data *pd)
@@ -658,7 +649,7 @@
 			if (!strcmp(port_name, "dsa") && link &&
 					pd->nr_chips > 1) {
 				ret = dsa_of_setup_routing_table(pd, cd,
-						chip_index, link);
+						chip_index, port_index, link);
 				if (ret)
 					goto out_free_chip;
 			}
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 57be71d..23b9b3e 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -1111,11 +1111,10 @@
 {
 	unsigned int i;
 
+	rtnl_lock();
 #ifdef CONFIG_IP_MULTIPLE_TABLES
 	fib4_rules_exit(net);
 #endif
-
-	rtnl_lock();
 	for (i = 0; i < FIB_TABLE_HASHSZ; i++) {
 		struct fib_table *tb;
 		struct hlist_head *head;
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 9282544..fe54eba 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -278,11 +278,13 @@
 {
 	struct mr_table *mrt, *next;
 
+	rtnl_lock();
 	list_for_each_entry_safe(mrt, next, &net->ipv4.mr_tables, list) {
 		list_del(&mrt->list);
 		ipmr_free_table(mrt);
 	}
 	fib_rules_unregister(net->ipv4.mr_rules_ops);
+	rtnl_unlock();
 }
 #else
 #define ipmr_for_each_table(mrt, net) \
@@ -308,7 +310,10 @@
 
 static void __net_exit ipmr_rules_exit(struct net *net)
 {
+	rtnl_lock();
 	ipmr_free_table(net->ipv4.mrt);
+	net->ipv4.mrt = NULL;
+	rtnl_unlock();
 }
 #endif
 
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index fb4cf8b..f501ac04 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -3105,10 +3105,11 @@
 			if (!first_ackt.v64)
 				first_ackt = last_ackt;
 
-			if (!(sacked & TCPCB_SACKED_ACKED))
+			if (!(sacked & TCPCB_SACKED_ACKED)) {
 				reord = min(pkts_acked, reord);
-			if (!after(scb->end_seq, tp->high_seq))
-				flag |= FLAG_ORIG_SACK_ACKED;
+				if (!after(scb->end_seq, tp->high_seq))
+					flag |= FLAG_ORIG_SACK_ACKED;
+			}
 		}
 
 		if (sacked & TCPCB_SACKED_ACKED)
diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c
index 27ca796..70bc6ab 100644
--- a/net/ipv6/fib6_rules.c
+++ b/net/ipv6/fib6_rules.c
@@ -322,7 +322,9 @@
 
 static void __net_exit fib6_rules_net_exit(struct net *net)
 {
+	rtnl_lock();
 	fib_rules_unregister(net->ipv6.fib6_rules_ops);
+	rtnl_unlock();
 }
 
 static struct pernet_operations fib6_rules_net_ops = {
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 7e80b61..36cf0ab 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -542,7 +542,8 @@
 {
 	struct sk_buff *frag;
 	struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
-	struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
+	struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
+				inet6_sk(skb->sk) : NULL;
 	struct ipv6hdr *tmp_hdr;
 	struct frag_hdr *fh;
 	unsigned int mtu, hlen, left, len;
diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index 52028f4..312e0ff 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -267,8 +267,8 @@
 		list_del(&mrt->list);
 		ip6mr_free_table(mrt);
 	}
-	rtnl_unlock();
 	fib_rules_unregister(net->ipv6.mr6_rules_ops);
+	rtnl_unlock();
 }
 #else
 #define ip6mr_for_each_table(mrt, net) \
@@ -336,7 +336,7 @@
 
 static void ip6mr_free_table(struct mr6_table *mrt)
 {
-	del_timer(&mrt->ipmr_expire_timer);
+	del_timer_sync(&mrt->ipmr_expire_timer);
 	mroute_clean_tables(mrt);
 	kfree(mrt);
 }
diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c
index 895348e..a29a504 100644
--- a/net/l2tp/l2tp_core.c
+++ b/net/l2tp/l2tp_core.c
@@ -1871,6 +1871,7 @@
 	l2tp_wq = alloc_workqueue("l2tp", WQ_UNBOUND, 0);
 	if (!l2tp_wq) {
 		pr_err("alloc_workqueue failed\n");
+		unregister_pernet_device(&l2tp_net_ops);
 		rc = -ENOMEM;
 		goto out;
 	}