kernel/linux.git/drivers/net/net_failover.c, branch v7.1-rc5

net: net_failover: Fix the deadlock in slave register

2026-05-14T02:01:03+00:00

There is netdev_lock_ops() before the NETDEV_REGISTER notifier in register_netdevice(), so use the non-locking functions in net_failover_slave_register(). failover_slave_register() in failover_existing_slave_register() adds lock and unlock ops too. Call Trace: __schedule+0x30d/0x7a0 schedule+0x27/0x90 schedule_preempt_disabled+0x15/0x30 __mutex_lock.constprop.0+0x538/0x9e0 __mutex_lock_slowpath+0x13/0x20 mutex_lock+0x3b/0x50 dev_set_mtu+0x40/0xe0 net_failover_slave_register+0x24/0x280 failover_slave_register+0x103/0x1b0 failover_event+0x15e/0x210 ? dropmon_net_event+0xac/0xe0 notifier_call_chain+0x5e/0xe0 raw_notifier_call_chain+0x16/0x30 call_netdevice_notifiers_info+0x52/0xa0 register_netdevice+0x5f4/0x7c0 register_netdev+0x1e/0x40 _mlx5e_probe+0xe2/0x370 [mlx5_core] mlx5e_probe+0x59/0x70 [mlx5_core] ? __pfx_mlx5e_probe+0x10/0x10 [mlx5_core] Fixes: 4c975fd70002 ("net: hold instance lock during NETDEV_REGISTER/UP") Signed-off-by: Faicker Mo Signed-off-by: Jakub Kicinski

net: remove unnecessary module_init/exit functions

2026-02-03T01:25:23+00:00

Many network drivers have unnecessary empty module_init and module_exit functions. Remove them (including some that just print a message). Note that if a module_init function exists, a module_exit function must also exist; otherwise, the module cannot be unloaded. Signed-off-by: Ethan Nelson-Moore Acked-by: Marc Kleine-Budde Acked-by: Michael Grzeschik Reviewed-by: Ido Schimmel Acked-by: Ping-Ke Shih Acked-by: Toke Høiland-Jørgensen Link: https://patch.msgid.link/20260131004327.18112-1-enelsonmoore@gmail.com Signed-off-by: Jakub Kicinski

net: rename netns_local to netns_immutable

2025-03-04T11:44:48+00:00

The name 'netns_local' is confusing. A following commit will export it via netlink, so let's use a more explicit name. Reported-by: Eric Dumazet Suggested-by: Kuniyuki Iwashima Signed-off-by: Nicolas Dichtel Reviewed-by: Kuniyuki Iwashima Signed-off-by: Paolo Abeni

netdev_features: convert NETIF_F_NETNS_LOCAL to dev->netns_local

2024-09-03T09:36:43+00:00

"Interface can't change network namespaces" is rather an attribute, not a feature, and it can't be changed via Ethtool. Make it a "cold" private flag instead of a netdev_feature and free one more bit. Signed-off-by: Alexander Lobakin Signed-off-by: Paolo Abeni

netdev_features: convert NETIF_F_LLTX to dev->lltx

2024-09-03T09:36:43+00:00

NETIF_F_LLTX can't be changed via Ethtool and is not a feature, rather an attribute, very similar to IFF_NO_QUEUE (and hot). Free one netdev_features_t bit and make it a "hot" private flag. Signed-off-by: Alexander Lobakin Signed-off-by: Paolo Abeni

net: annotate writes on dev->mtu from ndo_change_mtu()

2024-05-07T23:19:14+00:00

Simon reported that ndo_change_mtu() methods were never updated to use WRITE_ONCE(dev->mtu, new_mtu) as hinted in commit 501a90c94510 ("inet: protect against too small mtu values.") We read dev->mtu without holding RTNL in many places, with READ_ONCE() annotations. It is time to take care of ndo_change_mtu() methods to use corresponding WRITE_ONCE() Signed-off-by: Eric Dumazet Reported-by: Simon Horman Closes: https://lore.kernel.org/netdev/20240505144608.GB67882@kernel.org/ Reviewed-by: Jacob Keller Reviewed-by: Sabrina Dubroca Reviewed-by: Simon Horman Acked-by: Shannon Nelson Link: https://lore.kernel.org/r/20240506102812.3025432-1-edumazet@google.com Signed-off-by: Jakub Kicinski

net/net_failover: fix txq exceeding warning

2023-03-27T07:08:57+00:00

The failover txq is inited as 16 queues. when a packet is transmitted from the failover device firstly, the failover device will select the queue which is returned from the primary device if the primary device is UP and running. If the primary device txq is bigger than the default 16, it can lead to the following warning: eth0 selects TX queue 18, but real number of TX queues is 16 The warning backtrace is: [ 32.146376] CPU: 18 PID: 9134 Comm: chronyd Tainted: G E 6.2.8-1.el7.centos.x86_64 #1 [ 32.147175] Hardware name: Red Hat KVM, BIOS 1.10.2-3.el7_4.1 04/01/2014 [ 32.147730] Call Trace: [ 32.147971] [ 32.148183] dump_stack_lvl+0x48/0x70 [ 32.148514] dump_stack+0x10/0x20 [ 32.148820] netdev_core_pick_tx+0xb1/0xe0 [ 32.149180] __dev_queue_xmit+0x529/0xcf0 [ 32.149533] ? __check_object_size.part.0+0x21c/0x2c0 [ 32.149967] ip_finish_output2+0x278/0x560 [ 32.150327] __ip_finish_output+0x1fe/0x2f0 [ 32.150690] ip_finish_output+0x2a/0xd0 [ 32.151032] ip_output+0x7a/0x110 [ 32.151337] ? __pfx_ip_finish_output+0x10/0x10 [ 32.151733] ip_local_out+0x5e/0x70 [ 32.152054] ip_send_skb+0x19/0x50 [ 32.152366] udp_send_skb.isra.0+0x163/0x3a0 [ 32.152736] udp_sendmsg+0xba8/0xec0 [ 32.153060] ? __folio_memcg_unlock+0x25/0x60 [ 32.153445] ? __pfx_ip_generic_getfrag+0x10/0x10 [ 32.153854] ? sock_has_perm+0x85/0xa0 [ 32.154190] inet_sendmsg+0x6d/0x80 [ 32.154508] ? inet_sendmsg+0x6d/0x80 [ 32.154838] sock_sendmsg+0x62/0x70 [ 32.155152] ____sys_sendmsg+0x134/0x290 [ 32.155499] ___sys_sendmsg+0x81/0xc0 [ 32.155828] ? _get_random_bytes.part.0+0x79/0x1a0 [ 32.156240] ? ip4_datagram_release_cb+0x5f/0x1e0 [ 32.156649] ? get_random_u16+0x69/0xf0 [ 32.156989] ? __fget_light+0xcf/0x110 [ 32.157326] __sys_sendmmsg+0xc4/0x210 [ 32.157657] ? __sys_connect+0xb7/0xe0 [ 32.157995] ? __audit_syscall_entry+0xce/0x140 [ 32.158388] ? syscall_trace_enter.isra.0+0x12c/0x1a0 [ 32.158820] __x64_sys_sendmmsg+0x24/0x30 [ 32.159171] do_syscall_64+0x38/0x90 [ 32.159493] entry_SYSCALL_64_after_hwframe+0x72/0xdc Fix that by reducing txq number as the non-existent primary-dev does. Fixes: cfc80d9a1163 ("net: Introduce net_failover driver") Signed-off-by: Faicker Mo Signed-off-by: David S. Miller

net: move from strlcpy with unused retval to strscpy

2022-08-31T21:11:07+00:00

Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Signed-off-by: Wolfram Sang Acked-by: Marc Kleine-Budde # for CAN Link: https://lore.kernel.org/r/20220830201457.7984-1-wsa+renesas@sang-engineering.com Signed-off-by: Jakub Kicinski

net: add per-cpu storage and net->core_stats

2022-03-12T07:17:24+00:00

Before adding yet another possibly contended atomic_long_t, it is time to add per-cpu storage for existing ones: dev->tx_dropped, dev->rx_dropped, and dev->rx_nohandler Because many devices do not have to increment such counters, allocate the per-cpu storage on demand, so that dev_get_stats() does not have to spend considerable time folding zero counters. Note that some drivers have abused these counters which were supposed to be only used by core networking stack. v4: should use per_cpu_ptr() in dev_get_stats() (Jakub) v3: added a READ_ONCE() in netdev_core_stats_alloc() (Paolo) v2: add a missing include (reported by kernel test robot ) Change in netdev_core_stats_alloc() (Jakub) Signed-off-by: Eric Dumazet Cc: jeffreyji Reviewed-by: Brian Vazquez Reviewed-by: Jakub Kicinski Acked-by: Paolo Abeni Link: https://lore.kernel.org/r/20220311051420.2608812-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski

net: use dev_addr_set()

2021-10-09T10:55:01+00:00

Use dev_addr_set() instead of writing directly to netdev->dev_addr in various misc and old drivers. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller