Ivan Vecera f6988cb63a team: don't call netdev_change_features under team->lock ... The team_device_event() notifier calls team_compute_features() to fix vlan_features under team->lock to protect team->port_list. The problem is that subsequent __team_compute_features() calls netdev_change_features() to propagate vlan_features to upper vlan devices while team->lock is still taken. This can lead to deadlock when NETIF_F_LRO is modified on lower devices or team device itself. Example: The team0 as active backup with eth0 and eth1 NICs. Both eth0 & eth1 are LRO capable and LRO is enabled. Thus LRO is also enabled on team0. The command 'ethtool -K team0 lro off' now hangs due to this deadlock: dev_ethtool() -> ethtool_set_features() -> __netdev_update_features(team) -> netdev_sync_lower_features() -> netdev_update_features(lower_1) -> __netdev_update_features(lower_1) -> netdev_features_change(lower_1) -> call_netdevice_notifiers(...) -> team_device_event(lower_1) -> team_compute_features(team) [TAKES team->lock] -> netdev_change_features(team) -> __netdev_update_features(team) -> netdev_sync_lower_features() -> netdev_update_features(lower_2) -> __netdev_update_features(lower_2) -> netdev_features_change(lower_2) -> call_netdevice_notifiers(...) -> team_device_event(lower_2) -> team_compute_features(team) [DEADLOCK] The bug is present in team from the beginning but it appeared after the commit fd867d5 (net/core: generic support for disabling netdev features down stack) that adds synchronization of features with lower devices. Fixes: fd867d5 (net/core: generic support for disabling netdev features down stack) Cc: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Ivan Vecera <ivecera@redhat.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2016-05-25 12:58:04 -07:00
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Kconfig	team: introduce random mode	2013-03-06 14:55:20 -05:00
Makefile	team: introduce random mode	2013-03-06 14:55:20 -05:00
team_mode_activebackup.c	team: fill-up LAG changeupper info struct and pass it along	2015-12-03 11:49:26 -05:00
team_mode_broadcast.c	team: fill-up LAG changeupper info struct and pass it along	2015-12-03 11:49:26 -05:00
team_mode_loadbalance.c	team: fill-up LAG changeupper info struct and pass it along	2015-12-03 11:49:26 -05:00
team_mode_random.c	team: fill-up LAG changeupper info struct and pass it along	2015-12-03 11:49:26 -05:00
team_mode_roundrobin.c	team: fill-up LAG changeupper info struct and pass it along	2015-12-03 11:49:26 -05:00
team.c	team: don't call netdev_change_features under team->lock	2016-05-25 12:58:04 -07:00