From fbe168ba91f7c327856f205699404284c2f09e36 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Michal=20Kube=C4=8Dek?= Date: Thu, 13 Nov 2014 07:54:50 +0100 Subject: [PATCH] net: generic dev_disable_lro() stacked device handling Large receive offloading is known to cause problems if received packets are passed to other host. Therefore the kernel disables it by calling dev_disable_lro() whenever a network device is enslaved in a bridge or forwarding is enabled for it (or globally). For virtual devices we need to disable LRO on the underlying physical device (which is actually receiving the packets). Current dev_disable_lro() code handles this propagation for a vlan (including 802.1ad nested vlan), macvlan or a vlan on top of a macvlan. It doesn't handle other stacked devices and their combinations, in particular propagation from a bond to its slaves which often causes problems in virtualization setups. As we now have generic data structures describing the upper-lower device relationship, dev_disable_lro() can be generalized to disable LRO also for all lower devices (if any) once it is disabled for the device itself. For bonding and teaming devices, it is necessary to disable LRO not only on current slaves at the moment when dev_disable_lro() is called but also on any slave (port) added later. v2: use lower device links for all devices (including vlan and macvlan) Signed-off-by: Michal Kubecek Acked-by: Veaceslav Falico Signed-off-by: David S. Miller --- drivers/net/bonding/bond_main.c | 3 +++ drivers/net/team/team.c | 3 +++ net/core/dev.c | 15 +++++---------- 3 files changed, 11 insertions(+), 10 deletions(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index b9b34566b9b8..8575fee8b359 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -1526,6 +1526,9 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev) } #endif + if (!(bond_dev->features & NETIF_F_LRO)) + dev_disable_lro(slave_dev); + res = netdev_rx_handler_register(slave_dev, bond_handle_frame, new_slave); if (res) { diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c index 2368395d8ae5..93e224217e24 100644 --- a/drivers/net/team/team.c +++ b/drivers/net/team/team.c @@ -1179,6 +1179,9 @@ static int team_port_add(struct team *team, struct net_device *port_dev) goto err_enable_netpoll; } + if (!(dev->features & NETIF_F_LRO)) + dev_disable_lro(port_dev); + err = netdev_rx_handler_register(port_dev, team_handle_frame, port); if (err) { diff --git a/net/core/dev.c b/net/core/dev.c index bb09b0364619..1ab168e0fdf7 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1437,22 +1437,17 @@ EXPORT_SYMBOL(dev_close); */ void dev_disable_lro(struct net_device *dev) { - /* - * If we're trying to disable lro on a vlan device - * use the underlying physical device instead - */ - if (is_vlan_dev(dev)) - dev = vlan_dev_real_dev(dev); - - /* the same for macvlan devices */ - if (netif_is_macvlan(dev)) - dev = macvlan_dev_real_dev(dev); + struct net_device *lower_dev; + struct list_head *iter; dev->wanted_features &= ~NETIF_F_LRO; netdev_update_features(dev); if (unlikely(dev->features & NETIF_F_LRO)) netdev_WARN(dev, "failed to disable LRO!\n"); + + netdev_for_each_lower_dev(dev, lower_dev, iter) + dev_disable_lro(lower_dev); } EXPORT_SYMBOL(dev_disable_lro); -- 2.30.2