---

yaml
---
r: 215225
b: refs/heads/master
c: e843fa5
h: refs/heads/master
i:
  215223: a761265
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c2355e1ab910278a94d487b78590ee3c8eecd08a
+refs/heads/master: e843fa50887582c867d8b7995f81fe9c1a076806

trunk/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";
 
@@ -310,6 +315,7 @@ 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 +350,7 @@ static int bond_del_vlan(struct bonding *bond, unsigned short vlan_id)
 
 out:
 	write_unlock_bh(&bond->lock);
+	unblock_netpoll_tx();
 	return res;
 }
 
@@ -1804,10 +1811,6 @@ 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) {
 		bond_dev->priv_flags |= IFF_DISABLE_NETPOLL;
 	} else {
@@ -1892,6 +1895,7 @@ 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);
 
@@ -1901,6 +1905,7 @@ 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;
 	}
 
@@ -1994,6 +1999,7 @@ 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);
@@ -2085,6 +2091,7 @@ static int bond_release_all(struct net_device *bond_dev)
 	struct net_device *slave_dev;
 	struct sockaddr addr;
 
+	block_netpoll_tx();
 	write_lock_bh(&bond->lock);
 
 	netif_carrier_off(bond_dev);
@@ -2183,6 +2190,7 @@ static int bond_release_all(struct net_device *bond_dev)
 
 out:
 	write_unlock_bh(&bond->lock);
+	unblock_netpoll_tx();
 
 	return 0;
 }
@@ -2232,9 +2240,11 @@ 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;
 
@@ -2466,9 +2476,11 @@ 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);
@@ -2911,11 +2923,13 @@ 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:
@@ -3074,9 +3088,11 @@ 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);
@@ -4564,6 +4580,13 @@ 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;
@@ -5286,6 +5309,13 @@ 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;
@@ -5304,6 +5334,7 @@ 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();
@@ -5313,6 +5344,9 @@ static int __init bonding_init(void)
 	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;
 
 }
@@ -5327,6 +5361,10 @@ 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);

trunk/drivers/net/bonding/bond_sysfs.c

@@ -1066,6 +1066,7 @@ static ssize_t bonding_store_primary(struct device *d,
 
 	if (!rtnl_trylock())
 		return restart_syscall();
+	block_netpoll_tx();
 	read_lock(&bond->lock);
 	write_lock_bh(&bond->curr_slave_lock);
 
@@ -1101,6 +1102,7 @@ static ssize_t bonding_store_primary(struct device *d,
 out:
 	write_unlock_bh(&bond->curr_slave_lock);
 	read_unlock(&bond->lock);
+	unblock_netpoll_tx();
 	rtnl_unlock();
 
 	return count;
@@ -1146,11 +1148,13 @@ static ssize_t bonding_store_primary_reselect(struct device *d,
 		bond->dev->name, pri_reselect_tbl[new_value].modename,
 		new_value);
 
+	block_netpoll_tx();
 	read_lock(&bond->lock);
 	write_lock_bh(&bond->curr_slave_lock);
 	bond_select_active_slave(bond);
 	write_unlock_bh(&bond->curr_slave_lock);
 	read_unlock(&bond->lock);
+	unblock_netpoll_tx();
 out:
 	rtnl_unlock();
 	return ret;
@@ -1232,6 +1236,8 @@ static ssize_t bonding_store_active_slave(struct device *d,
 
 	if (!rtnl_trylock())
 		return restart_syscall();
+
+	block_netpoll_tx();
 	read_lock(&bond->lock);
 	write_lock_bh(&bond->curr_slave_lock);
 
@@ -1288,6 +1294,8 @@ static ssize_t bonding_store_active_slave(struct device *d,
  out:
 	write_unlock_bh(&bond->curr_slave_lock);
 	read_unlock(&bond->lock);
+	unblock_netpoll_tx();
+
 	rtnl_unlock();
 
 	return count;

trunk/drivers/net/bonding/bonding.h

@@ -19,6 +19,7 @@
 #include <linux/proc_fs.h>
 #include <linux/if_bonding.h>
 #include <linux/kobject.h>
+#include <linux/cpumask.h>
 #include <linux/in6.h>
 #include "bond_3ad.h"
 #include "bond_alb.h"
@@ -117,6 +118,35 @@
 		bond_for_each_slave_from(bond, pos, cnt, (bond)->first_slave)
 
 
+#ifdef CONFIG_NET_POLL_CONTROLLER
+extern cpumask_var_t netpoll_block_tx;
+
+static inline void block_netpoll_tx(void)
+{
+	preempt_disable();
+	BUG_ON(cpumask_test_and_set_cpu(smp_processor_id(),
+					netpoll_block_tx));
+}
+
+static inline void unblock_netpoll_tx(void)
+{
+	BUG_ON(!cpumask_test_and_clear_cpu(smp_processor_id(),
+					   netpoll_block_tx));
+	preempt_enable();
+}
+
+static inline int is_netpoll_tx_blocked(struct net_device *dev)
+{
+	if (unlikely(dev->priv_flags & IFF_IN_NETPOLL))
+		return cpumask_test_cpu(smp_processor_id(), netpoll_block_tx);
+	return 0;
+}
+#else
+#define block_netpoll_tx()
+#define unblock_netpoll_tx()
+#define is_netpoll_tx_blocked(dev) (0)
+#endif
+
 struct bond_params {
 	int mode;
 	int xmit_policy;