Merge branch 'net-core-fix-a-lockdep-splat-in-the-dev_addr_list'

Taehee Yoo says:

====================
net: core: fix a lockdep splat in the dev_addr_list.

This patchset is to avoid lockdep splat.

When a stacked interface graph is changed, netif_addr_lock() is called
recursively and it internally calls spin_lock_nested().
The parameter of spin_lock_nested() is 'dev->lower_level',
this is called subclass.
The problem of 'dev->lower_level' is that while 'dev->lower_level' is
being used as a subclass of spin_lock_nested(), its value can be changed.
So, spin_lock_nested() would be called recursively with the same
subclass value, the lockdep understands a deadlock.
In order to avoid this, a new variable is needed and it is going to be
used as a parameter of spin_lock_nested().
The first and second patch is a preparation patch for the third patch.
In the third patch, the problem will be fixed.

The first patch is to add __netdev_upper_dev_unlink().
An existed netdev_upper_dev_unlink() is renamed to
__netdev_upper_dev_unlink(). and netdev_upper_dev_unlink()
is added as an wrapper of this function.

The second patch is to add the netdev_nested_priv structure.
netdev_walk_all_{ upper | lower }_dev() pass both private functions
and "data" pointer to handle their own things.
At this point, the data pointer type is void *.
In order to make it easier to expand common variables and functions,
this new netdev_nested_priv structure is added.

The third patch is to add a new variable 'nested_level'
into the net_device structure.
This variable will be used as a parameter of spin_lock_nested() of
dev->addr_list_lock.
Due to this variable, it can avoid lockdep splat.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/infiniband/core/cache.c

@@ -1320,9 +1320,10 @@ struct net_device *rdma_read_gid_attr_ndev_rcu(const struct ib_gid_attr *attr)
 }
 EXPORT_SYMBOL(rdma_read_gid_attr_ndev_rcu);
 
-static int get_lower_dev_vlan(struct net_device *lower_dev, void *data)
+static int get_lower_dev_vlan(struct net_device *lower_dev,
+			      struct netdev_nested_priv *priv)
 {
-	u16 *vlan_id = data;
+	u16 *vlan_id = (u16 *)priv->data;
 
 	if (is_vlan_dev(lower_dev))
 		*vlan_id = vlan_dev_vlan_id(lower_dev);
@@ -1348,6 +1349,9 @@ static int get_lower_dev_vlan(struct net_device *lower_dev, void *data)
 int rdma_read_gid_l2_fields(const struct ib_gid_attr *attr,
 			    u16 *vlan_id, u8 *smac)
 {
+	struct netdev_nested_priv priv = {
+		.data = (void *)vlan_id,
+	};
 	struct net_device *ndev;
 
 	rcu_read_lock();
@@ -1368,7 +1372,7 @@ int rdma_read_gid_l2_fields(const struct ib_gid_attr *attr,
 			 * the lower vlan device for this gid entry.
 			 */
 			netdev_walk_all_lower_dev_rcu(attr->ndev,
-					get_lower_dev_vlan, vlan_id);
+					get_lower_dev_vlan, &priv);
 		}
 	}
 	rcu_read_unlock();

drivers/infiniband/core/cma.c

@@ -2865,9 +2865,10 @@ struct iboe_prio_tc_map {
 	bool found;
 };
 
-static int get_lower_vlan_dev_tc(struct net_device *dev, void *data)
+static int get_lower_vlan_dev_tc(struct net_device *dev,
+				 struct netdev_nested_priv *priv)
 {
-	struct iboe_prio_tc_map *map = data;
+	struct iboe_prio_tc_map *map = (struct iboe_prio_tc_map *)priv->data;
 
 	if (is_vlan_dev(dev))
 		map->output_tc = get_vlan_ndev_tc(dev, map->input_prio);
@@ -2886,16 +2887,18 @@ static int iboe_tos_to_sl(struct net_device *ndev, int tos)
 {
 	struct iboe_prio_tc_map prio_tc_map = {};
 	int prio = rt_tos2priority(tos);
+	struct netdev_nested_priv priv;
 
 	/* If VLAN device, get it directly from the VLAN netdev */
 	if (is_vlan_dev(ndev))
 		return get_vlan_ndev_tc(ndev, prio);
 
 	prio_tc_map.input_prio = prio;
+	priv.data = (void *)&prio_tc_map;
 	rcu_read_lock();
 	netdev_walk_all_lower_dev_rcu(ndev,
 				      get_lower_vlan_dev_tc,
-				      &prio_tc_map);
+				      &priv);
 	rcu_read_unlock();
 	/* If map is found from lower device, use it; Otherwise
 	 * continue with the current netdevice to get priority to tc map.

drivers/infiniband/core/roce_gid_mgmt.c

@@ -531,10 +531,11 @@ struct upper_list {
 	struct net_device *upper;
 };
 
-static int netdev_upper_walk(struct net_device *upper, void *data)
+static int netdev_upper_walk(struct net_device *upper,
+			     struct netdev_nested_priv *priv)
 {
 	struct upper_list *entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
-	struct list_head *upper_list = data;
+	struct list_head *upper_list = (struct list_head *)priv->data;
 
 	if (!entry)
 		return 0;
@@ -553,12 +554,14 @@ static void handle_netdev_upper(struct ib_device *ib_dev, u8 port,
 						      struct net_device *ndev))
 {
 	struct net_device *ndev = cookie;
+	struct netdev_nested_priv priv;
 	struct upper_list *upper_iter;
 	struct upper_list *upper_temp;
 	LIST_HEAD(upper_list);
 
+	priv.data = &upper_list;
 	rcu_read_lock();
-	netdev_walk_all_upper_dev_rcu(ndev, netdev_upper_walk, &upper_list);
+	netdev_walk_all_upper_dev_rcu(ndev, netdev_upper_walk, &priv);
 	rcu_read_unlock();
 
 	handle_netdev(ib_dev, port, ndev);

drivers/infiniband/ulp/ipoib/ipoib_main.c

@@ -342,9 +342,10 @@ struct ipoib_walk_data {
 	struct net_device *result;
 };
 
-static int ipoib_upper_walk(struct net_device *upper, void *_data)
+static int ipoib_upper_walk(struct net_device *upper,
+			    struct netdev_nested_priv *priv)
 {
-	struct ipoib_walk_data *data = _data;
+	struct ipoib_walk_data *data = (struct ipoib_walk_data *)priv->data;
 	int ret = 0;
 
 	if (ipoib_is_dev_match_addr_rcu(data->addr, upper)) {
@@ -368,18 +369,20 @@ static int ipoib_upper_walk(struct net_device *upper, void *_data)
 static struct net_device *ipoib_get_net_dev_match_addr(
 		const struct sockaddr *addr, struct net_device *dev)
 {
+	struct netdev_nested_priv priv;
 	struct ipoib_walk_data data = {
 		.addr = addr,
 	};
 
+	priv.data = (void *)&data;
 	rcu_read_lock();
 	if (ipoib_is_dev_match_addr_rcu(addr, dev)) {
 		dev_hold(dev);
 		data.result = dev;
 		goto out;
 	}
 
-	netdev_walk_all_upper_dev_rcu(dev, ipoib_upper_walk, &data);
+	netdev_walk_all_upper_dev_rcu(dev, ipoib_upper_walk, &priv);
 out:
 	rcu_read_unlock();
 	return data.result;

drivers/net/bonding/bond_alb.c

@@ -942,9 +942,10 @@ struct alb_walk_data {
 	bool strict_match;
 };
 
-static int alb_upper_dev_walk(struct net_device *upper, void *_data)
+static int alb_upper_dev_walk(struct net_device *upper,
+			      struct netdev_nested_priv *priv)
 {
-	struct alb_walk_data *data = _data;
+	struct alb_walk_data *data = (struct alb_walk_data *)priv->data;
 	bool strict_match = data->strict_match;
 	struct bonding *bond = data->bond;
 	struct slave *slave = data->slave;
@@ -983,21 +984,23 @@ static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
 				      bool strict_match)
 {
 	struct bonding *bond = bond_get_bond_by_slave(slave);
+	struct netdev_nested_priv priv;
 	struct alb_walk_data data = {
 		.strict_match = strict_match,
 		.mac_addr = mac_addr,
 		.slave = slave,
 		.bond = bond,
 	};
 
+	priv.data = (void *)&data;
 	/* send untagged */
 	alb_send_lp_vid(slave, mac_addr, 0, 0);
 
 	/* loop through all devices and see if we need to send a packet
 	 * for that device.
 	 */
 	rcu_read_lock();
-	netdev_walk_all_upper_dev_rcu(bond->dev, alb_upper_dev_walk, &data);
+	netdev_walk_all_upper_dev_rcu(bond->dev, alb_upper_dev_walk, &priv);
 	rcu_read_unlock();
 }
 

drivers/net/bonding/bond_main.c

@@ -2511,22 +2511,26 @@ static void bond_mii_monitor(struct work_struct *work)
 	}
 }
 
-static int bond_upper_dev_walk(struct net_device *upper, void *data)
+static int bond_upper_dev_walk(struct net_device *upper,
+			       struct netdev_nested_priv *priv)
 {
-	__be32 ip = *((__be32 *)data);
+	__be32 ip = *(__be32 *)priv->data;
 
 	return ip == bond_confirm_addr(upper, 0, ip);
 }
 
 static bool bond_has_this_ip(struct bonding *bond, __be32 ip)
 {
+	struct netdev_nested_priv priv = {
+		.data = (void *)&ip,
+	};
 	bool ret = false;
 
 	if (ip == bond_confirm_addr(bond->dev, 0, ip))
 		return true;
 
 	rcu_read_lock();
-	if (netdev_walk_all_upper_dev_rcu(bond->dev, bond_upper_dev_walk, &ip))
+	if (netdev_walk_all_upper_dev_rcu(bond->dev, bond_upper_dev_walk, &priv))
 		ret = true;
 	rcu_read_unlock();
 

drivers/net/ethernet/intel/ixgbe/ixgbe_main.c

@@ -5396,9 +5396,10 @@ static int ixgbe_fwd_ring_up(struct ixgbe_adapter *adapter,
 	return err;
 }
 
-static int ixgbe_macvlan_up(struct net_device *vdev, void *data)
+static int ixgbe_macvlan_up(struct net_device *vdev,
+			    struct netdev_nested_priv *priv)
 {
-	struct ixgbe_adapter *adapter = data;
+	struct ixgbe_adapter *adapter = (struct ixgbe_adapter *)priv->data;
 	struct ixgbe_fwd_adapter *accel;
 
 	if (!netif_is_macvlan(vdev))
@@ -5415,8 +5416,12 @@ static int ixgbe_macvlan_up(struct net_device *vdev, void *data)
 
 static void ixgbe_configure_dfwd(struct ixgbe_adapter *adapter)
 {
+	struct netdev_nested_priv priv = {
+		.data = (void *)adapter,
+	};
+
 	netdev_walk_all_upper_dev_rcu(adapter->netdev,
-				      ixgbe_macvlan_up, adapter);
+				      ixgbe_macvlan_up, &priv);
 }
 
 static void ixgbe_configure(struct ixgbe_adapter *adapter)
@@ -9023,9 +9028,10 @@ static void ixgbe_set_prio_tc_map(struct ixgbe_adapter *adapter)
 }
 
 #endif /* CONFIG_IXGBE_DCB */
-static int ixgbe_reassign_macvlan_pool(struct net_device *vdev, void *data)
+static int ixgbe_reassign_macvlan_pool(struct net_device *vdev,
+				       struct netdev_nested_priv *priv)
 {
-	struct ixgbe_adapter *adapter = data;
+	struct ixgbe_adapter *adapter = (struct ixgbe_adapter *)priv->data;
 	struct ixgbe_fwd_adapter *accel;
 	int pool;
 
@@ -9062,13 +9068,16 @@ static int ixgbe_reassign_macvlan_pool(struct net_device *vdev, void *data)
 static void ixgbe_defrag_macvlan_pools(struct net_device *dev)
 {
 	struct ixgbe_adapter *adapter = netdev_priv(dev);
+	struct netdev_nested_priv priv = {
+		.data = (void *)adapter,
+	};
 
 	/* flush any stale bits out of the fwd bitmask */
 	bitmap_clear(adapter->fwd_bitmask, 1, 63);
 
 	/* walk through upper devices reassigning pools */
 	netdev_walk_all_upper_dev_rcu(dev, ixgbe_reassign_macvlan_pool,
-				      adapter);
+				      &priv);
 }
 
 /**
@@ -9242,14 +9251,18 @@ struct upper_walk_data {
 	u8 queue;
 };
 
-static int get_macvlan_queue(struct net_device *upper, void *_data)
+static int get_macvlan_queue(struct net_device *upper,
+			     struct netdev_nested_priv *priv)
 {
 	if (netif_is_macvlan(upper)) {
 		struct ixgbe_fwd_adapter *vadapter = macvlan_accel_priv(upper);
-		struct upper_walk_data *data = _data;
-		struct ixgbe_adapter *adapter = data->adapter;
-		int ifindex = data->ifindex;
+		struct ixgbe_adapter *adapter;
+		struct upper_walk_data *data;
+		int ifindex;
 
+		data = (struct upper_walk_data *)priv->data;
+		ifindex = data->ifindex;
+		adapter = data->adapter;
 		if (vadapter && upper->ifindex == ifindex) {
 			data->queue = adapter->rx_ring[vadapter->rx_base_queue]->reg_idx;
 			data->action = data->queue;
@@ -9265,6 +9278,7 @@ static int handle_redirect_action(struct ixgbe_adapter *adapter, int ifindex,
 {
 	struct ixgbe_ring_feature *vmdq = &adapter->ring_feature[RING_F_VMDQ];
 	unsigned int num_vfs = adapter->num_vfs, vf;
+	struct netdev_nested_priv priv;
 	struct upper_walk_data data;
 	struct net_device *upper;
 
@@ -9284,8 +9298,9 @@ static int handle_redirect_action(struct ixgbe_adapter *adapter, int ifindex,
 	data.ifindex = ifindex;
 	data.action = 0;
 	data.queue = 0;
+	priv.data = (void *)&data;
 	if (netdev_walk_all_upper_dev_rcu(adapter->netdev,
-					  get_macvlan_queue, &data)) {
+					  get_macvlan_queue, &priv)) {
 		*action = data.action;
 		*queue = data.queue;
 

drivers/net/ethernet/mellanox/mlxsw/spectrum.c

@@ -3690,13 +3690,13 @@ bool mlxsw_sp_port_dev_check(const struct net_device *dev)
 	return dev->netdev_ops == &mlxsw_sp_port_netdev_ops;
 }
 
-static int mlxsw_sp_lower_dev_walk(struct net_device *lower_dev, void *data)
+static int mlxsw_sp_lower_dev_walk(struct net_device *lower_dev,
+				   struct netdev_nested_priv *priv)
 {
-	struct mlxsw_sp_port **p_mlxsw_sp_port = data;
 	int ret = 0;
 
 	if (mlxsw_sp_port_dev_check(lower_dev)) {
-		*p_mlxsw_sp_port = netdev_priv(lower_dev);
+		priv->data = (void *)netdev_priv(lower_dev);
 		ret = 1;
 	}
 
@@ -3705,15 +3705,16 @@ static int mlxsw_sp_lower_dev_walk(struct net_device *lower_dev, void *data)
 
 struct mlxsw_sp_port *mlxsw_sp_port_dev_lower_find(struct net_device *dev)
 {
-	struct mlxsw_sp_port *mlxsw_sp_port;
+	struct netdev_nested_priv priv = {
+		.data = NULL,
+	};
 
 	if (mlxsw_sp_port_dev_check(dev))
 		return netdev_priv(dev);
 
-	mlxsw_sp_port = NULL;
-	netdev_walk_all_lower_dev(dev, mlxsw_sp_lower_dev_walk, &mlxsw_sp_port);
+	netdev_walk_all_lower_dev(dev, mlxsw_sp_lower_dev_walk, &priv);
 
-	return mlxsw_sp_port;
+	return (struct mlxsw_sp_port *)priv.data;
 }
 
 struct mlxsw_sp *mlxsw_sp_lower_get(struct net_device *dev)
@@ -3726,16 +3727,17 @@ struct mlxsw_sp *mlxsw_sp_lower_get(struct net_device *dev)
 
 struct mlxsw_sp_port *mlxsw_sp_port_dev_lower_find_rcu(struct net_device *dev)
 {
-	struct mlxsw_sp_port *mlxsw_sp_port;
+	struct netdev_nested_priv priv = {
+		.data = NULL,
+	};
 
 	if (mlxsw_sp_port_dev_check(dev))
 		return netdev_priv(dev);
 
-	mlxsw_sp_port = NULL;
 	netdev_walk_all_lower_dev_rcu(dev, mlxsw_sp_lower_dev_walk,
-				      &mlxsw_sp_port);
+				      &priv);
 
-	return mlxsw_sp_port;
+	return (struct mlxsw_sp_port *)priv.data;
 }
 
 struct mlxsw_sp_port *mlxsw_sp_port_lower_dev_hold(struct net_device *dev)

drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c

@@ -7351,9 +7351,10 @@ int mlxsw_sp_netdevice_vrf_event(struct net_device *l3_dev, unsigned long event,
 	return err;
 }
 
-static int __mlxsw_sp_rif_macvlan_flush(struct net_device *dev, void *data)
+static int __mlxsw_sp_rif_macvlan_flush(struct net_device *dev,
+					struct netdev_nested_priv *priv)
 {
-	struct mlxsw_sp_rif *rif = data;
+	struct mlxsw_sp_rif *rif = (struct mlxsw_sp_rif *)priv->data;
 
 	if (!netif_is_macvlan(dev))
 		return 0;
@@ -7364,12 +7365,16 @@ static int __mlxsw_sp_rif_macvlan_flush(struct net_device *dev, void *data)
 
 static int mlxsw_sp_rif_macvlan_flush(struct mlxsw_sp_rif *rif)
 {
+	struct netdev_nested_priv priv = {
+		.data = (void *)rif,
+	};
+
 	if (!netif_is_macvlan_port(rif->dev))
 		return 0;
 
 	netdev_warn(rif->dev, "Router interface is deleted. Upper macvlans will not work\n");
 	return netdev_walk_all_upper_dev_rcu(rif->dev,
-					     __mlxsw_sp_rif_macvlan_flush, rif);
+					     __mlxsw_sp_rif_macvlan_flush, &priv);
 }
 
 static void mlxsw_sp_rif_subport_setup(struct mlxsw_sp_rif *rif,