1 files changed, 177 insertions, 320 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 820bac2..8341dad 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -139,7 +139,6 @@
 #include <linux/errqueue.h>
 #include <linux/hrtimer.h>
 #include <linux/netfilter_ingress.h>
-#include <linux/sctp.h>
 #include <linux/crash_dump.h>
 
 #include "net-sysfs.h"
@@ -2492,141 +2491,6 @@ out:
 }
 EXPORT_SYMBOL(skb_checksum_help);
 
-/* skb_csum_offload_check - Driver helper function to determine if a device
- * with limited checksum offload capabilities is able to offload the checksum
- * for a given packet.
- *
- * Arguments:
- *   skb - sk_buff for the packet in question
- *   spec - contains the description of what device can offload
- *   csum_encapped - returns true if the checksum being offloaded is
- *	      encpasulated. That is it is checksum for the transport header
- *	      in the inner headers.
- *   checksum_help - when set indicates that helper function should
- *	      call skb_checksum_help if offload checks fail
- *
- * Returns:
- *   true: Packet has passed the checksum checks and should be offloadable to
- *	   the device (a driver may still need to check for additional
- *	   restrictions of its device)
- *   false: Checksum is not offloadable. If checksum_help was set then
- *	   skb_checksum_help was called to resolve checksum for non-GSO
- *	   packets and when IP protocol is not SCTP
- */
-bool __skb_csum_offload_chk(struct sk_buff *skb,
-			    const struct skb_csum_offl_spec *spec,
-			    bool *csum_encapped,
-			    bool csum_help)
-{
-	struct iphdr *iph;
-	struct ipv6hdr *ipv6;
-	void *nhdr;
-	int protocol;
-	u8 ip_proto;
-
-	if (skb->protocol == htons(ETH_P_8021Q) ||
-	    skb->protocol == htons(ETH_P_8021AD)) {
-		if (!spec->vlan_okay)
-			goto need_help;
-	}
-
-	/* We check whether the checksum refers to a transport layer checksum in
-	 * the outermost header or an encapsulated transport layer checksum that
-	 * corresponds to the inner headers of the skb. If the checksum is for
-	 * something else in the packet we need help.
-	 */
-	if (skb_checksum_start_offset(skb) == skb_transport_offset(skb)) {
-		/* Non-encapsulated checksum */
-		protocol = eproto_to_ipproto(vlan_get_protocol(skb));
-		nhdr = skb_network_header(skb);
-		*csum_encapped = false;
-		if (spec->no_not_encapped)
-			goto need_help;
-	} else if (skb->encapsulation && spec->encap_okay &&
-		   skb_checksum_start_offset(skb) ==
-		   skb_inner_transport_offset(skb)) {
-		/* Encapsulated checksum */
-		*csum_encapped = true;
-		switch (skb->inner_protocol_type) {
-		case ENCAP_TYPE_ETHER:
-			protocol = eproto_to_ipproto(skb->inner_protocol);
-			break;
-		case ENCAP_TYPE_IPPROTO:
-			protocol = skb->inner_protocol;
-			break;
-		}
-		nhdr = skb_inner_network_header(skb);
-	} else {
-		goto need_help;
-	}
-
-	switch (protocol) {
-	case IPPROTO_IP:
-		if (!spec->ipv4_okay)
-			goto need_help;
-		iph = nhdr;
-		ip_proto = iph->protocol;
-		if (iph->ihl != 5 && !spec->ip_options_okay)
-			goto need_help;
-		break;
-	case IPPROTO_IPV6:
-		if (!spec->ipv6_okay)
-			goto need_help;
-		if (spec->no_encapped_ipv6 && *csum_encapped)
-			goto need_help;
-		ipv6 = nhdr;
-		nhdr += sizeof(*ipv6);
-		ip_proto = ipv6->nexthdr;
-		break;
-	default:
-		goto need_help;
-	}
-
-ip_proto_again:
-	switch (ip_proto) {
-	case IPPROTO_TCP:
-		if (!spec->tcp_okay ||
-		    skb->csum_offset != offsetof(struct tcphdr, check))
-			goto need_help;
-		break;
-	case IPPROTO_UDP:
-		if (!spec->udp_okay ||
-		    skb->csum_offset != offsetof(struct udphdr, check))
-			goto need_help;
-		break;
-	case IPPROTO_SCTP:
-		if (!spec->sctp_okay ||
-		    skb->csum_offset != offsetof(struct sctphdr, checksum))
-			goto cant_help;
-		break;
-	case NEXTHDR_HOP:
-	case NEXTHDR_ROUTING:
-	case NEXTHDR_DEST: {
-		u8 *opthdr = nhdr;
-
-		if (protocol != IPPROTO_IPV6 || !spec->ext_hdrs_okay)
-			goto need_help;
-
-		ip_proto = opthdr[0];
-		nhdr += (opthdr[1] + 1) << 3;
-
-		goto ip_proto_again;
-	}
-	default:
-		goto need_help;
-	}
-
-	/* Passed the tests for offloading checksum */
-	return true;
-
-need_help:
-	if (csum_help && !skb_shinfo(skb)->gso_size)
-		skb_checksum_help(skb);
-cant_help:
-	return false;
-}
-EXPORT_SYMBOL(__skb_csum_offload_chk);
-
 __be16 skb_network_protocol(struct sk_buff *skb, int *depth)
 {
 	__be16 type = skb->protocol;
@@ -5275,6 +5139,13 @@ static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev,
 	return NULL;
 }
 
+static int __netdev_has_upper_dev(struct net_device *upper_dev, void *data)
+{
+	struct net_device *dev = data;
+
+	return upper_dev == dev;
+}
+
 /**
  * netdev_has_upper_dev - Check if device is linked to an upper device
  * @dev: device
@@ -5289,11 +5160,30 @@ bool netdev_has_upper_dev(struct net_device *dev,
 {
 	ASSERT_RTNL();
 
-	return __netdev_find_adj(upper_dev, &dev->all_adj_list.upper);
+	return netdev_walk_all_upper_dev_rcu(dev, __netdev_has_upper_dev,
+					     upper_dev);
 }
 EXPORT_SYMBOL(netdev_has_upper_dev);
 
 /**
+ * netdev_has_upper_dev_all - Check if device is linked to an upper device
+ * @dev: device
+ * @upper_dev: upper device to check
+ *
+ * Find out if a device is linked to specified upper device and return true
+ * in case it is. Note that this checks the entire upper device chain.
+ * The caller must hold rcu lock.
+ */
+
+bool netdev_has_upper_dev_all_rcu(struct net_device *dev,
+				  struct net_device *upper_dev)
+{
+	return !!netdev_walk_all_upper_dev_rcu(dev, __netdev_has_upper_dev,
+					       upper_dev);
+}
+EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu);
+
+/**
  * netdev_has_any_upper_dev - Check if device is linked to some device
  * @dev: device
  *
@@ -5304,7 +5194,7 @@ static bool netdev_has_any_upper_dev(struct net_device *dev)
 {
 	ASSERT_RTNL();
 
-	return !list_empty(&dev->all_adj_list.upper);
+	return !list_empty(&dev->adj_list.upper);
 }
 
 /**
@@ -5331,6 +5221,20 @@ struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
 }
 EXPORT_SYMBOL(netdev_master_upper_dev_get);
 
+/**
+ * netdev_has_any_lower_dev - Check if device is linked to some device
+ * @dev: device
+ *
+ * Find out if a device is linked to a lower device and return true in case
+ * it is. The caller must hold the RTNL lock.
+ */
+static bool netdev_has_any_lower_dev(struct net_device *dev)
+{
+	ASSERT_RTNL();
+
+	return !list_empty(&dev->adj_list.lower);
+}
+
 void *netdev_adjacent_get_private(struct list_head *adj_list)
 {
 	struct netdev_adjacent *adj;
@@ -5367,16 +5271,8 @@ struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
 }
 EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);
 
-/**
- * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
- * @dev: device
- * @iter: list_head ** of the current position
- *
- * Gets the next device from the dev's upper list, starting from iter
- * position. The caller must hold RCU read lock.
- */
-struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
-						     struct list_head **iter)
+static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev,
+						    struct list_head **iter)
 {
 	struct netdev_adjacent *upper;
 
@@ -5384,14 +5280,41 @@ struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
 
 	upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
 
-	if (&upper->list == &dev->all_adj_list.upper)
+	if (&upper->list == &dev->adj_list.upper)
 		return NULL;
 
 	*iter = &upper->list;
 
 	return upper->dev;
 }
-EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
+
+int netdev_walk_all_upper_dev_rcu(struct net_device *dev,
+				  int (*fn)(struct net_device *dev,
+					    void *data),
+				  void *data)
+{
+	struct net_device *udev;
+	struct list_head *iter;
+	int ret;
+
+	for (iter = &dev->adj_list.upper,
+	     udev = netdev_next_upper_dev_rcu(dev, &iter);
+	     udev;
+	     udev = netdev_next_upper_dev_rcu(dev, &iter)) {
+		/* first is the upper device itself */
+		ret = fn(udev, data);
+		if (ret)
+			return ret;
+
+		/* then look at all of its upper devices */
+		ret = netdev_walk_all_upper_dev_rcu(udev, fn, data);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu);
 
 /**
  * netdev_lower_get_next_private - Get the next ->private from the
@@ -5474,55 +5397,90 @@ void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
 }
 EXPORT_SYMBOL(netdev_lower_get_next);
 
-/**
- * netdev_all_lower_get_next - Get the next device from all lower neighbour list
- * @dev: device
- * @iter: list_head ** of the current position
- *
- * Gets the next netdev_adjacent from the dev's all lower neighbour
- * list, starting from iter position. The caller must hold RTNL lock or
- * its own locking that guarantees that the neighbour all lower
- * list will remain unchanged.
- */
-struct net_device *netdev_all_lower_get_next(struct net_device *dev, struct list_head **iter)
+static struct net_device *netdev_next_lower_dev(struct net_device *dev,
+						struct list_head **iter)
 {
 	struct netdev_adjacent *lower;
 
-	lower = list_entry(*iter, struct netdev_adjacent, list);
+	lower = list_entry((*iter)->next, struct netdev_adjacent, list);
 
-	if (&lower->list == &dev->all_adj_list.lower)
+	if (&lower->list == &dev->adj_list.lower)
 		return NULL;
 
-	*iter = lower->list.next;
+	*iter = &lower->list;
 
 	return lower->dev;
 }
-EXPORT_SYMBOL(netdev_all_lower_get_next);
 
-/**
- * netdev_all_lower_get_next_rcu - Get the next device from all
- *				   lower neighbour list, RCU variant
- * @dev: device
- * @iter: list_head ** of the current position
- *
- * Gets the next netdev_adjacent from the dev's all lower neighbour
- * list, starting from iter position. The caller must hold RCU read lock.
- */
-struct net_device *netdev_all_lower_get_next_rcu(struct net_device *dev,
-						 struct list_head **iter)
+int netdev_walk_all_lower_dev(struct net_device *dev,
+			      int (*fn)(struct net_device *dev,
+					void *data),
+			      void *data)
+{
+	struct net_device *ldev;
+	struct list_head *iter;
+	int ret;
+
+	for (iter = &dev->adj_list.lower,
+	     ldev = netdev_next_lower_dev(dev, &iter);
+	     ldev;
+	     ldev = netdev_next_lower_dev(dev, &iter)) {
+		/* first is the lower device itself */
+		ret = fn(ldev, data);
+		if (ret)
+			return ret;
+
+		/* then look at all of its lower devices */
+		ret = netdev_walk_all_lower_dev(ldev, fn, data);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev);
+
+static struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev,
+						    struct list_head **iter)
 {
 	struct netdev_adjacent *lower;
 
 	lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
-
-	if (&lower->list == &dev->all_adj_list.lower)
+	if (&lower->list == &dev->adj_list.lower)
 		return NULL;
 
 	*iter = &lower->list;
 
 	return lower->dev;
 }
-EXPORT_SYMBOL(netdev_all_lower_get_next_rcu);
+
+int netdev_walk_all_lower_dev_rcu(struct net_device *dev,
+				  int (*fn)(struct net_device *dev,
+					    void *data),
+				  void *data)
+{
+	struct net_device *ldev;
+	struct list_head *iter;
+	int ret;
+
+	for (iter = &dev->adj_list.lower,
+	     ldev = netdev_next_lower_dev_rcu(dev, &iter);
+	     ldev;
+	     ldev = netdev_next_lower_dev_rcu(dev, &iter)) {
+		/* first is the lower device itself */
+		ret = fn(ldev, data);
+		if (ret)
+			return ret;
+
+		/* then look at all of its lower devices */
+		ret = netdev_walk_all_lower_dev_rcu(ldev, fn, data);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu);
 
 /**
  * netdev_lower_get_first_private_rcu - Get the first ->private from the
@@ -5595,7 +5553,6 @@ static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev,
 
 static int __netdev_adjacent_dev_insert(struct net_device *dev,
 					struct net_device *adj_dev,
-					u16 ref_nr,
 					struct list_head *dev_list,
 					void *private, bool master)
 {
@@ -5605,7 +5562,10 @@ static int __netdev_adjacent_dev_insert(struct net_device *dev,
 	adj = __netdev_find_adj(adj_dev, dev_list);
 
 	if (adj) {
-		adj->ref_nr += ref_nr;
+		adj->ref_nr += 1;
+		pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n",
+			 dev->name, adj_dev->name, adj->ref_nr);
+
 		return 0;
 	}
 
@@ -5615,12 +5575,12 @@ static int __netdev_adjacent_dev_insert(struct net_device *dev,
 
 	adj->dev = adj_dev;
 	adj->master = master;
-	adj->ref_nr = ref_nr;
+	adj->ref_nr = 1;
 	adj->private = private;
 	dev_hold(adj_dev);
 
-	pr_debug("dev_hold for %s, because of link added from %s to %s\n",
-		 adj_dev->name, dev->name, adj_dev->name);
+	pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n",
+		 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name);
 
 	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
 		ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
@@ -5659,17 +5619,22 @@ static void __netdev_adjacent_dev_remove(struct net_device *dev,
 {
 	struct netdev_adjacent *adj;
 
+	pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n",
+		 dev->name, adj_dev->name, ref_nr);
+
 	adj = __netdev_find_adj(adj_dev, dev_list);
 
 	if (!adj) {
-		pr_err("tried to remove device %s from %s\n",
+		pr_err("Adjacency does not exist for device %s from %s\n",
 		       dev->name, adj_dev->name);
-		BUG();
+		WARN_ON(1);
+		return;
 	}
 
 	if (adj->ref_nr > ref_nr) {
-		pr_debug("%s to %s ref_nr-%d = %d\n", dev->name, adj_dev->name,
-			 ref_nr, adj->ref_nr-ref_nr);
+		pr_debug("adjacency: %s to %s ref_nr - %d = %d\n",
+			 dev->name, adj_dev->name, ref_nr,
+			 adj->ref_nr - ref_nr);
 		adj->ref_nr -= ref_nr;
 		return;
 	}
@@ -5681,7 +5646,7 @@ static void __netdev_adjacent_dev_remove(struct net_device *dev,
 		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
 
 	list_del_rcu(&adj->list);
-	pr_debug("dev_put for %s, because link removed from %s to %s\n",
+	pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n",
 		 adj_dev->name, dev->name, adj_dev->name);
 	dev_put(adj_dev);
 	kfree_rcu(adj, rcu);
@@ -5689,38 +5654,27 @@ static void __netdev_adjacent_dev_remove(struct net_device *dev,
 
 static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
 					    struct net_device *upper_dev,
-					    u16 ref_nr,
 					    struct list_head *up_list,
 					    struct list_head *down_list,
 					    void *private, bool master)
 {
 	int ret;
 
-	ret = __netdev_adjacent_dev_insert(dev, upper_dev, ref_nr, up_list,
+	ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list,
 					   private, master);
 	if (ret)
 		return ret;
 
-	ret = __netdev_adjacent_dev_insert(upper_dev, dev, ref_nr, down_list,
+	ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list,
 					   private, false);
 	if (ret) {
-		__netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list);
+		__netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list);
 		return ret;
 	}
 
 	return 0;
 }
 
-static int __netdev_adjacent_dev_link(struct net_device *dev,
-				      struct net_device *upper_dev,
-				      u16 ref_nr)
-{
-	return __netdev_adjacent_dev_link_lists(dev, upper_dev, ref_nr,
-						&dev->all_adj_list.upper,
-						&upper_dev->all_adj_list.lower,
-						NULL, false);
-}
-
 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
 					       struct net_device *upper_dev,
 					       u16 ref_nr,
@@ -5731,40 +5685,19 @@ static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
 	__netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list);
 }
 
-static void __netdev_adjacent_dev_unlink(struct net_device *dev,
-					 struct net_device *upper_dev,
-					 u16 ref_nr)
-{
-	__netdev_adjacent_dev_unlink_lists(dev, upper_dev, ref_nr,
-					   &dev->all_adj_list.upper,
-					   &upper_dev->all_adj_list.lower);
-}
-
 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
 						struct net_device *upper_dev,
 						void *private, bool master)
 {
-	int ret = __netdev_adjacent_dev_link(dev, upper_dev, 1);
-
-	if (ret)
-		return ret;
-
-	ret = __netdev_adjacent_dev_link_lists(dev, upper_dev, 1,
-					       &dev->adj_list.upper,
-					       &upper_dev->adj_list.lower,
-					       private, master);
-	if (ret) {
-		__netdev_adjacent_dev_unlink(dev, upper_dev, 1);
-		return ret;
-	}
-
-	return 0;
+	return __netdev_adjacent_dev_link_lists(dev, upper_dev,
+						&dev->adj_list.upper,
+						&upper_dev->adj_list.lower,
+						private, master);
 }
 
 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
 						   struct net_device *upper_dev)
 {
-	__netdev_adjacent_dev_unlink(dev, upper_dev, 1);
 	__netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1,
 					   &dev->adj_list.upper,
 					   &upper_dev->adj_list.lower);
@@ -5775,7 +5708,6 @@ static int __netdev_upper_dev_link(struct net_device *dev,
 				   void *upper_priv, void *upper_info)
 {
 	struct netdev_notifier_changeupper_info changeupper_info;
-	struct netdev_adjacent *i, *j, *to_i, *to_j;
 	int ret = 0;
 
 	ASSERT_RTNL();
@@ -5784,10 +5716,10 @@ static int __netdev_upper_dev_link(struct net_device *dev,
 		return -EBUSY;
 
 	/* To prevent loops, check if dev is not upper device to upper_dev. */
-	if (__netdev_find_adj(dev, &upper_dev->all_adj_list.upper))
+	if (netdev_has_upper_dev(upper_dev, dev))
 		return -EBUSY;
 
-	if (__netdev_find_adj(upper_dev, &dev->adj_list.upper))
+	if (netdev_has_upper_dev(dev, upper_dev))
 		return -EEXIST;
 
 	if (master && netdev_master_upper_dev_get(dev))
@@ -5809,80 +5741,15 @@ static int __netdev_upper_dev_link(struct net_device *dev,
 	if (ret)
 		return ret;
 
-	/* Now that we linked these devs, make all the upper_dev's
-	 * all_adj_list.upper visible to every dev's all_adj_list.lower an
-	 * versa, and don't forget the devices itself. All of these
-	 * links are non-neighbours.
-	 */
-	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
-		list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
-			pr_debug("Interlinking %s with %s, non-neighbour\n",
-				 i->dev->name, j->dev->name);
-			ret = __netdev_adjacent_dev_link(i->dev, j->dev, i->ref_nr);
-			if (ret)
-				goto rollback_mesh;
-		}
-	}
-
-	/* add dev to every upper_dev's upper device */
-	list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
-		pr_debug("linking %s's upper device %s with %s\n",
-			 upper_dev->name, i->dev->name, dev->name);
-		ret = __netdev_adjacent_dev_link(dev, i->dev, i->ref_nr);
-		if (ret)
-			goto rollback_upper_mesh;
-	}
-
-	/* add upper_dev to every dev's lower device */
-	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
-		pr_debug("linking %s's lower device %s with %s\n", dev->name,
-			 i->dev->name, upper_dev->name);
-		ret = __netdev_adjacent_dev_link(i->dev, upper_dev, i->ref_nr);
-		if (ret)
-			goto rollback_lower_mesh;
-	}
-
 	ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev,
 					    &changeupper_info.info);
 	ret = notifier_to_errno(ret);
 	if (ret)
-		goto rollback_lower_mesh;
+		goto rollback;
 
 	return 0;
 
-rollback_lower_mesh:
-	to_i = i;
-	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
-		if (i == to_i)
-			break;
-		__netdev_adjacent_dev_unlink(i->dev, upper_dev, i->ref_nr);
-	}
-
-	i = NULL;
-
-rollback_upper_mesh:
-	to_i = i;
-	list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
-		if (i == to_i)
-			break;
-		__netdev_adjacent_dev_unlink(dev, i->dev, i->ref_nr);
-	}
-
-	i = j = NULL;
-
-rollback_mesh:
-	to_i = i;
-	to_j = j;
-	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
-		list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
-			if (i == to_i && j == to_j)
-				break;
-			__netdev_adjacent_dev_unlink(i->dev, j->dev, i->ref_nr);
-		}
-		if (i == to_i)
-			break;
-	}
-
+rollback:
 	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
 
 	return ret;
@@ -5939,7 +5806,6 @@ void netdev_upper_dev_unlink(struct net_device *dev,
 			     struct net_device *upper_dev)
 {
 	struct netdev_notifier_changeupper_info changeupper_info;
-	struct netdev_adjacent *i, *j;
 	ASSERT_RTNL();
 
 	changeupper_info.upper_dev = upper_dev;
@@ -5951,23 +5817,6 @@ void netdev_upper_dev_unlink(struct net_device *dev,
 
 	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
 
-	/* Here is the tricky part. We must remove all dev's lower
-	 * devices from all upper_dev's upper devices and vice
-	 * versa, to maintain the graph relationship.
-	 */
-	list_for_each_entry(i, &dev->all_adj_list.lower, list)
-		list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
-			__netdev_adjacent_dev_unlink(i->dev, j->dev, i->ref_nr);
-
-	/* remove also the devices itself from lower/upper device
-	 * list
-	 */
-	list_for_each_entry(i, &dev->all_adj_list.lower, list)
-		__netdev_adjacent_dev_unlink(i->dev, upper_dev, i->ref_nr);
-
-	list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
-		__netdev_adjacent_dev_unlink(dev, i->dev, i->ref_nr);
-
 	call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev,
 				      &changeupper_info.info);
 }
@@ -6505,9 +6354,18 @@ int dev_set_mtu(struct net_device *dev, int new_mtu)
 	if (new_mtu == dev->mtu)
 		return 0;
 
-	/*	MTU must be positive.	 */
-	if (new_mtu < 0)
+	/* MTU must be positive, and in range */
+	if (new_mtu < 0 || new_mtu < dev->min_mtu) {
+		net_err_ratelimited("%s: Invalid MTU %d requested, hw min %d\n",
+				    dev->name, new_mtu, dev->min_mtu);
 		return -EINVAL;
+	}
+
+	if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) {
+		net_err_ratelimited("%s: Invalid MTU %d requested, hw max %d\n",
+				    dev->name, new_mtu, dev->max_mtu);
+		return -EINVAL;
+	}
 
 	if (!netif_device_present(dev))
 		return -ENODEV;
@@ -6782,6 +6640,7 @@ static void rollback_registered_many(struct list_head *head)
 
 		/* Notifier chain MUST detach us all upper devices. */
 		WARN_ON(netdev_has_any_upper_dev(dev));
+		WARN_ON(netdev_has_any_lower_dev(dev));
 
 		/* Remove entries from kobject tree */
 		netdev_unregister_kobject(dev);
@@ -7660,8 +7519,6 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
 	INIT_LIST_HEAD(&dev->link_watch_list);
 	INIT_LIST_HEAD(&dev->adj_list.upper);
 	INIT_LIST_HEAD(&dev->adj_list.lower);
-	INIT_LIST_HEAD(&dev->all_adj_list.upper);
-	INIT_LIST_HEAD(&dev->all_adj_list.lower);
 	INIT_LIST_HEAD(&dev->ptype_all);
 	INIT_LIST_HEAD(&dev->ptype_specific);
 #ifdef CONFIG_NET_SCHED