1 files changed, 59 insertions, 30 deletions

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 7703d35de65d..6b9a7bd8ec14 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -76,6 +76,7 @@
 #include <linux/if_vlan.h>
 #include <linux/if_bonding.h>
 #include <linux/jiffies.h>
+#include <linux/preempt.h>
 #include <net/route.h>
 #include <net/net_namespace.h>
 #include <net/netns/generic.h>
@@ -169,6 +170,10 @@ MODULE_PARM_DESC(resend_igmp, "Number of IGMP membership reports to send on link
 
 /*----------------------------- Global variables ----------------------------*/
 
+#ifdef CONFIG_NET_POLL_CONTROLLER
+cpumask_var_t netpoll_block_tx;
+#endif
+
 static const char * const version =
         DRV_DESCRIPTION ": v" DRV_VERSION " (" DRV_RELDATE ")\n";
 
@@ -179,9 +184,6 @@ static int arp_ip_count;
 static int bond_mode    = BOND_MODE_ROUNDROBIN;
 static int xmit_hashtype = BOND_XMIT_POLICY_LAYER2;
 static int lacp_fast;
-#ifdef CONFIG_NET_POLL_CONTROLLER
-static int disable_netpoll = 1;
-#endif
 
 const struct bond_parm_tbl bond_lacp_tbl[] = {
 {       "slow",         AD_LACP_SLOW},
@@ -310,6 +312,7 @@ static int bond_del_vlan(struct bonding *bond, unsigned short vlan_id)
 
         pr_debug("bond: %s, vlan id %d\n", bond->dev->name, vlan_id);
 
+        block_netpoll_tx();
         write_lock_bh(&bond->lock);
 
         list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
@@ -344,6 +347,7 @@ static int bond_del_vlan(struct bonding *bond, unsigned short vlan_id)
 
 out:
         write_unlock_bh(&bond->lock);
+        unblock_netpoll_tx();
         return res;
 }
 
@@ -449,11 +453,9 @@ int bond_dev_queue_xmit(struct bonding *bond, struct sk_buff *skb,
         if (unlikely(bond->dev->priv_flags & IFF_IN_NETPOLL)) {
                 struct netpoll *np = bond->dev->npinfo->netpoll;
                 slave_dev->npinfo = bond->dev->npinfo;
-                np->real_dev = np->dev = skb->dev;
                 slave_dev->priv_flags |= IFF_IN_NETPOLL;
-                netpoll_send_skb(np, skb);
+                netpoll_send_skb_on_dev(np, skb, slave_dev);
                 slave_dev->priv_flags &= ~IFF_IN_NETPOLL;
-                np->dev = bond->dev;
         } else
 #endif
                 dev_queue_xmit(skb);
@@ -1332,9 +1334,14 @@ static bool slaves_support_netpoll(struct net_device *bond_dev)
 
 static void bond_poll_controller(struct net_device *bond_dev)
 {
-        struct net_device *dev = bond_dev->npinfo->netpoll->real_dev;
-        if (dev != bond_dev)
-                netpoll_poll_dev(dev);
+        struct bonding *bond = netdev_priv(bond_dev);
+        struct slave *slave;
+        int i;
+
+        bond_for_each_slave(bond, slave, i) {
+                if (slave->dev && IS_UP(slave->dev))
+                        netpoll_poll_dev(slave->dev);
+        }
 }
 
 static void bond_netpoll_cleanup(struct net_device *bond_dev)
@@ -1801,23 +1808,15 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
         bond_set_carrier(bond);
 
 #ifdef CONFIG_NET_POLL_CONTROLLER
-        /*
-         * Netpoll and bonding is broken, make sure it is not initialized
-         * until it is fixed.
-         */
-        if (disable_netpoll) {
+        if (slaves_support_netpoll(bond_dev)) {
+                bond_dev->priv_flags &= ~IFF_DISABLE_NETPOLL;
+                if (bond_dev->npinfo)
+                        slave_dev->npinfo = bond_dev->npinfo;
+        } else if (!(bond_dev->priv_flags & IFF_DISABLE_NETPOLL)) {
                 bond_dev->priv_flags |= IFF_DISABLE_NETPOLL;
-        } else {
-                if (slaves_support_netpoll(bond_dev)) {
-                        bond_dev->priv_flags &= ~IFF_DISABLE_NETPOLL;
-                        if (bond_dev->npinfo)
-                                slave_dev->npinfo = bond_dev->npinfo;
-                } else if (!(bond_dev->priv_flags & IFF_DISABLE_NETPOLL)) {
-                        bond_dev->priv_flags |= IFF_DISABLE_NETPOLL;
-                        pr_info("New slave device %s does not support netpoll\n",
-                                slave_dev->name);
-                        pr_info("Disabling netpoll support for %s\n", bond_dev->name);
-                }
+                pr_info("New slave device %s does not support netpoll\n",
+                        slave_dev->name);
+                pr_info("Disabling netpoll support for %s\n", bond_dev->name);
         }
 #endif
         read_unlock(&bond->lock);
@@ -1889,6 +1888,7 @@ int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
                 return -EINVAL;
         }
 
+        block_netpoll_tx();
         netdev_bonding_change(bond_dev, NETDEV_BONDING_DESLAVE);
         write_lock_bh(&bond->lock);
 
@@ -1898,6 +1898,7 @@ int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
                 pr_info("%s: %s not enslaved\n",
                         bond_dev->name, slave_dev->name);
                 write_unlock_bh(&bond->lock);
+                unblock_netpoll_tx();
                 return -EINVAL;
         }
 
@@ -1991,6 +1992,7 @@ int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
         }
 
         write_unlock_bh(&bond->lock);
+        unblock_netpoll_tx();
 
         /* must do this from outside any spinlocks */
         bond_destroy_slave_symlinks(bond_dev, slave_dev);
@@ -2021,10 +2023,8 @@ int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
 #ifdef CONFIG_NET_POLL_CONTROLLER
         read_lock_bh(&bond->lock);
 
-         /* Make sure netpoll over stays disabled until fixed. */
-        if (!disable_netpoll)
-                if (slaves_support_netpoll(bond_dev))
-                                bond_dev->priv_flags &= ~IFF_DISABLE_NETPOLL;
+        if (slaves_support_netpoll(bond_dev))
+                bond_dev->priv_flags &= ~IFF_DISABLE_NETPOLL;
         read_unlock_bh(&bond->lock);
         if (slave_dev->netdev_ops->ndo_netpoll_cleanup)
                 slave_dev->netdev_ops->ndo_netpoll_cleanup(slave_dev);
@@ -2180,7 +2180,6 @@ static int bond_release_all(struct net_device *bond_dev)
 
 out:
         write_unlock_bh(&bond->lock);
-
         return 0;
 }
 
@@ -2229,9 +2228,11 @@ static int bond_ioctl_change_active(struct net_device *bond_dev, struct net_devi
             (old_active) &&
             (new_active->link == BOND_LINK_UP) &&
             IS_UP(new_active->dev)) {
+                block_netpoll_tx();
                 write_lock_bh(&bond->curr_slave_lock);
                 bond_change_active_slave(bond, new_active);
                 write_unlock_bh(&bond->curr_slave_lock);
+                unblock_netpoll_tx();
         } else
                 res = -EINVAL;
 
@@ -2463,9 +2464,11 @@ static void bond_miimon_commit(struct bonding *bond)
 
 do_failover:
                 ASSERT_RTNL();
+                block_netpoll_tx();
                 write_lock_bh(&bond->curr_slave_lock);
                 bond_select_active_slave(bond);
                 write_unlock_bh(&bond->curr_slave_lock);
+                unblock_netpoll_tx();
         }
 
         bond_set_carrier(bond);
@@ -2908,11 +2911,13 @@ void bond_loadbalance_arp_mon(struct work_struct *work)
         }
 
         if (do_failover) {
+                block_netpoll_tx();
                 write_lock_bh(&bond->curr_slave_lock);
 
                 bond_select_active_slave(bond);
 
                 write_unlock_bh(&bond->curr_slave_lock);
+                unblock_netpoll_tx();
         }
 
 re_arm:
@@ -3071,9 +3076,11 @@ static void bond_ab_arp_commit(struct bonding *bond, int delta_in_ticks)
 
 do_failover:
                 ASSERT_RTNL();
+                block_netpoll_tx();
                 write_lock_bh(&bond->curr_slave_lock);
                 bond_select_active_slave(bond);
                 write_unlock_bh(&bond->curr_slave_lock);
+                unblock_netpoll_tx();
         }
 
         bond_set_carrier(bond);
@@ -4561,6 +4568,13 @@ static netdev_tx_t bond_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
         struct bonding *bond = netdev_priv(dev);
 
+        /*
+         * If we risk deadlock from transmitting this in the
+         * netpoll path, tell netpoll to queue the frame for later tx
+         */
+        if (is_netpoll_tx_blocked(dev))
+                return NETDEV_TX_BUSY;
+
         if (TX_QUEUE_OVERRIDE(bond->params.mode)) {
                 if (!bond_slave_override(bond, skb))
                         return NETDEV_TX_OK;
@@ -5283,6 +5297,13 @@ static int __init bonding_init(void)
         if (res)
                 goto out;
 
+#ifdef CONFIG_NET_POLL_CONTROLLER
+        if (!alloc_cpumask_var(&netpoll_block_tx, GFP_KERNEL)) {
+                res = -ENOMEM;
+                goto out;
+        }
+#endif
+
         res = register_pernet_subsys(&bond_net_ops);
         if (res)
                 goto out;
@@ -5301,6 +5322,7 @@ static int __init bonding_init(void)
         if (res)
                 goto err;
 
+
         register_netdevice_notifier(&bond_netdev_notifier);
         register_inetaddr_notifier(&bond_inetaddr_notifier);
         bond_register_ipv6_notifier();
@@ -5310,6 +5332,9 @@ err:
         rtnl_link_unregister(&bond_link_ops);
 err_link:
         unregister_pernet_subsys(&bond_net_ops);
+#ifdef CONFIG_NET_POLL_CONTROLLER
+        free_cpumask_var(netpoll_block_tx);
+#endif
         goto out;
 
 }
@@ -5324,6 +5349,10 @@ static void __exit bonding_exit(void)
 
         rtnl_link_unregister(&bond_link_ops);
         unregister_pernet_subsys(&bond_net_ops);
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+        free_cpumask_var(netpoll_block_tx);
+#endif
 }
 
 module_init(bonding_init);