net/mlx4_en: Fix mac_hash database inconsistency

Using a local copy of dev_addr in mlx4_en_set_mac() to prevent dev_addr
from being modified during error flow or when dev_addr is modified in
another context (which is another problem that is being discussed over
the mailing list [1]).
Also fixing bad naming of priv->prev_mac into priv->current_mac.

[1] - http://patchwork.ozlabs.org/patch/351489/

Reviewed-by: Eyal Perry <eyalpe@mellanox.com>
Signed-off-by: Noa Osherovich <noaos@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 14 insertions, 9 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index 255950adcc6b..f384b354c88d 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -760,21 +760,22 @@ static int mlx4_en_replace_mac(struct mlx4_en_priv *priv, int qpn,
         return __mlx4_replace_mac(dev, priv->port, qpn, new_mac_u64);
 }
 
-static int mlx4_en_do_set_mac(struct mlx4_en_priv *priv)
+static int mlx4_en_do_set_mac(struct mlx4_en_priv *priv,
+                              unsigned char new_mac[ETH_ALEN + 2])
 {
         int err = 0;
 
         if (priv->port_up) {
                 /* Remove old MAC and insert the new one */
                 err = mlx4_en_replace_mac(priv, priv->base_qpn,
-                                          priv->dev->dev_addr, priv->prev_mac);
+                                          new_mac, priv->current_mac);
                 if (err)
                         en_err(priv, "Failed changing HW MAC address\n");
         } else
                 en_dbg(HW, priv, "Port is down while registering mac, exiting...\n");
 
-        memcpy(priv->prev_mac, priv->dev->dev_addr,
-               sizeof(priv->prev_mac));
+        if (!err)
+                memcpy(priv->current_mac, new_mac, sizeof(priv->current_mac));
 
         return err;
 }
@@ -784,14 +785,17 @@ static int mlx4_en_set_mac(struct net_device *dev, void *addr)
         struct mlx4_en_priv *priv = netdev_priv(dev);
         struct mlx4_en_dev *mdev = priv->mdev;
         struct sockaddr *saddr = addr;
+        unsigned char new_mac[ETH_ALEN + 2];
         int err;
 
         if (!is_valid_ether_addr(saddr->sa_data))
                 return -EADDRNOTAVAIL;
 
         mutex_lock(&mdev->state_lock);
-        memcpy(dev->dev_addr, saddr->sa_data, ETH_ALEN);
-        err = mlx4_en_do_set_mac(priv);
+        memcpy(new_mac, saddr->sa_data, ETH_ALEN);
+        err = mlx4_en_do_set_mac(priv, new_mac);
+        if (!err)
+                memcpy(dev->dev_addr, saddr->sa_data, ETH_ALEN);
         mutex_unlock(&mdev->state_lock);
 
         return err;
@@ -1156,7 +1160,8 @@ static void mlx4_en_do_uc_filter(struct mlx4_en_priv *priv,
                         }
 
                         /* MAC address of the port is not in uc list */
-                        if (ether_addr_equal_64bits(entry->mac, dev->dev_addr))
+                        if (ether_addr_equal_64bits(entry->mac,
+                                                    priv->current_mac))
                                 found = true;
 
                         if (!found) {
@@ -1466,7 +1471,7 @@ static void mlx4_en_do_get_stats(struct work_struct *work)
                 queue_delayed_work(mdev->workqueue, &priv->stats_task, STATS_DELAY);
         }
         if (mdev->mac_removed[MLX4_MAX_PORTS + 1 - priv->port]) {
-                mlx4_en_do_set_mac(priv);
+                mlx4_en_do_set_mac(priv, priv->current_mac);
                 mdev->mac_removed[MLX4_MAX_PORTS + 1 - priv->port] = 0;
         }
         mutex_unlock(&mdev->state_lock);
@@ -2524,7 +2529,7 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int port,
                 }
         }
 
-        memcpy(priv->prev_mac, dev->dev_addr, sizeof(priv->prev_mac));
+        memcpy(priv->current_mac, dev->dev_addr, sizeof(priv->current_mac));
 
         priv->stride = roundup_pow_of_two(sizeof(struct mlx4_en_rx_desc) +
                                           DS_SIZE * MLX4_EN_MAX_RX_FRAGS);