Merge branch 'bridge-gso-segs-and-size'

Eric Dumazet says:

====================
net: propagate max_gso_segs and max_gso_size

bridge code does not properly update max_gso_segs and max_gso_size.

Since this was not really obvious, first patch adds two new rtnetlink
attributes to help debugging this kind of issues (ip -d link)

Second patch fixes bridge code.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/uapi/linux/if_link.h

@@ -153,6 +153,8 @@ enum {
 	IFLA_LINK_NETNSID,
 	IFLA_PHYS_PORT_NAME,
 	IFLA_PROTO_DOWN,
+	IFLA_GSO_MAX_SEGS,
+	IFLA_GSO_MAX_SIZE,
 	__IFLA_MAX
 };
 

net/bridge/br_if.c

@@ -437,6 +437,20 @@ int br_min_mtu(const struct net_bridge *br)
 	return mtu;
 }
 
+static void br_set_gso_limits(struct net_bridge *br)
+{
+	unsigned int gso_max_size = GSO_MAX_SIZE;
+	u16 gso_max_segs = GSO_MAX_SEGS;
+	const struct net_bridge_port *p;
+
+	list_for_each_entry(p, &br->port_list, list) {
+		gso_max_size = min(gso_max_size, p->dev->gso_max_size);
+		gso_max_segs = min(gso_max_segs, p->dev->gso_max_segs);
+	}
+	br->dev->gso_max_size = gso_max_size;
+	br->dev->gso_max_segs = gso_max_segs;
+}
+
 /*
  * Recomputes features using slave's features
  */
@@ -564,6 +578,7 @@ int br_add_if(struct net_bridge *br, struct net_device *dev)
 		call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
 
 	dev_set_mtu(br->dev, br_min_mtu(br));
+	br_set_gso_limits(br);
 
 	kobject_uevent(&p->kobj, KOBJ_ADD);
 
@@ -610,6 +625,7 @@ int br_del_if(struct net_bridge *br, struct net_device *dev)
 	del_nbp(p);
 
 	dev_set_mtu(br->dev, br_min_mtu(br));
+	br_set_gso_limits(br);
 
 	spin_lock_bh(&br->lock);
 	changed_addr = br_stp_recalculate_bridge_id(br);

net/core/rtnetlink.c

@@ -895,6 +895,8 @@ static noinline size_t if_nlmsg_size(const struct net_device *dev,
 	       + nla_total_size(4) /* IFLA_PROMISCUITY */
 	       + nla_total_size(4) /* IFLA_NUM_TX_QUEUES */
 	       + nla_total_size(4) /* IFLA_NUM_RX_QUEUES */
+	       + nla_total_size(4) /* IFLA_MAX_GSO_SEGS */
+	       + nla_total_size(4) /* IFLA_MAX_GSO_SIZE */
 	       + nla_total_size(1) /* IFLA_OPERSTATE */
 	       + nla_total_size(1) /* IFLA_LINKMODE */
 	       + nla_total_size(4) /* IFLA_CARRIER_CHANGES */
@@ -1223,6 +1225,8 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
 	    nla_put_u32(skb, IFLA_GROUP, dev->group) ||
 	    nla_put_u32(skb, IFLA_PROMISCUITY, dev->promiscuity) ||
 	    nla_put_u32(skb, IFLA_NUM_TX_QUEUES, dev->num_tx_queues) ||
+	    nla_put_u32(skb, IFLA_GSO_MAX_SEGS, dev->gso_max_segs) ||
+	    nla_put_u32(skb, IFLA_GSO_MAX_SIZE, dev->gso_max_size) ||
 #ifdef CONFIG_RPS
 	    nla_put_u32(skb, IFLA_NUM_RX_QUEUES, dev->num_rx_queues) ||
 #endif