From 11687a1099583273a8a98ec42af62b5bb5a69e45 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Thu, 25 Jun 2009 02:45:42 -0700 Subject: [PATCH] Revert "veth: prevent oops caused by netdev destructor" This reverts commit ae0e8e82205c903978a79ebf5e31c670b61fa5b4. This change had two problems: 1) Since it frees the stats in the drivers' close method, we can OOPS in the transmit routine. 2) stats are no longer remembered across ifdown/ifup which disagrees with how every other device operates. Thanks to analysis and test patch from Serge E. Hallyn and initial OOPS report by Sachin Sant. Signed-off-by: David S. Miller --- drivers/net/veth.c | 41 +++++++++++++++++++++++++---------------- 1 file changed, 25 insertions(+), 16 deletions(-) diff --git a/drivers/net/veth.c b/drivers/net/veth.c index 87197dd9c788..1097c72e44d5 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -208,11 +208,14 @@ static int veth_xmit(struct sk_buff *skb, struct net_device *dev) static struct net_device_stats *veth_get_stats(struct net_device *dev) { - struct veth_priv *priv = netdev_priv(dev); - struct net_device_stats *dev_stats = &dev->stats; - unsigned int cpu; + struct veth_priv *priv; + struct net_device_stats *dev_stats; + int cpu; struct veth_net_stats *stats; + priv = netdev_priv(dev); + dev_stats = &dev->stats; + dev_stats->rx_packets = 0; dev_stats->tx_packets = 0; dev_stats->rx_bytes = 0; @@ -220,17 +223,16 @@ static struct net_device_stats *veth_get_stats(struct net_device *dev) dev_stats->tx_dropped = 0; dev_stats->rx_dropped = 0; - if (priv->stats) - for_each_online_cpu(cpu) { - stats = per_cpu_ptr(priv->stats, cpu); + for_each_online_cpu(cpu) { + stats = per_cpu_ptr(priv->stats, cpu); - dev_stats->rx_packets += stats->rx_packets; - dev_stats->tx_packets += stats->tx_packets; - dev_stats->rx_bytes += stats->rx_bytes; - dev_stats->tx_bytes += stats->tx_bytes; - dev_stats->tx_dropped += stats->tx_dropped; - dev_stats->rx_dropped += stats->rx_dropped; - } + dev_stats->rx_packets += stats->rx_packets; + dev_stats->tx_packets += stats->tx_packets; + dev_stats->rx_bytes += stats->rx_bytes; + dev_stats->tx_bytes += stats->tx_bytes; + dev_stats->tx_dropped += stats->tx_dropped; + dev_stats->rx_dropped += stats->rx_dropped; + } return dev_stats; } @@ -257,8 +259,6 @@ static int veth_close(struct net_device *dev) netif_carrier_off(dev); netif_carrier_off(priv->peer); - free_percpu(priv->stats); - priv->stats = NULL; return 0; } @@ -289,6 +289,15 @@ static int veth_dev_init(struct net_device *dev) return 0; } +static void veth_dev_free(struct net_device *dev) +{ + struct veth_priv *priv; + + priv = netdev_priv(dev); + free_percpu(priv->stats); + free_netdev(dev); +} + static const struct net_device_ops veth_netdev_ops = { .ndo_init = veth_dev_init, .ndo_open = veth_open, @@ -306,7 +315,7 @@ static void veth_setup(struct net_device *dev) dev->netdev_ops = &veth_netdev_ops; dev->ethtool_ops = &veth_ethtool_ops; dev->features |= NETIF_F_LLTX; - dev->destructor = free_netdev; + dev->destructor = veth_dev_free; } /*