linux-toradex.git/net/core/dev.c, branch v6.18-rc2 Linux kernel for Apalis and Colibri modules net: core: fix lockdep splat on device unregister 2025-10-15T02:27:20+00:00 Florian Westphal fw@strlen.de 2025-10-13T18:50:52+00:00 7f0fddd817ba6daebea1445ae9fab4b6d2294fa8 Since blamed commit, unregister_netdevice_many_notify() takes the netdev mutex if the device needs it. If the device list is too long, this will lock more device mutexes than lockdep can handle: unshare -n \ bash -c 'for i in $(seq 1 100);do ip link add foo$i type dummy;done' BUG: MAX_LOCK_DEPTH too low! turning off the locking correctness validator. depth: 48 max: 48! 48 locks held by kworker/u16:1/69: #0: ..148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work #1: ..d40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work #2: ..bd0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net #3: ..aa8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch #4: ..cb0 (&dev_instance_lock_key#3){+.+.}-{4:4}, at: unregister_netdevice_many_notify [..] Add a helper to close and then unlock a list of net_devices. Devices that are not up have to be skipped - netif_close_many always removes them from the list without any other actions taken, so they'd remain in locked state. Close devices whenever we've used up half of the tracking slots or we processed entire list without hitting the limit. Fixes: 7e4d784f5810 ("net: hold netdev instance lock during rtnetlink operations") Signed-off-by: Florian Westphal <fw@strlen.de> Link: https://patch.msgid.link/20251013185052.14021-1-fw@strlen.de Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Since blamed commit, unregister_netdevice_many_notify() takes the netdev
mutex if the device needs it.

If the device list is too long, this will lock more device mutexes than
lockdep can handle:

unshare -n \
 bash -c 'for i in $(seq 1 100);do ip link add foo$i type dummy;done'

BUG: MAX_LOCK_DEPTH too low!
turning off the locking correctness validator.
depth: 48  max: 48!
48 locks held by kworker/u16:1/69:
 #0: ..148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work
 #1: ..d40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work
 #2: ..bd0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net
 #3: ..aa8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch
 #4: ..cb0 (&dev_instance_lock_key#3){+.+.}-{4:4}, at: unregister_netdevice_many_notify
[..]

Add a helper to close and then unlock a list of net_devices.
Devices that are not up have to be skipped - netif_close_many always
removes them from the list without any other actions taken, so they'd
remain in locked state.

Close devices whenever we've used up half of the tracking slots or we
processed entire list without hitting the limit.

Fixes: 7e4d784f5810 ("net: hold netdev instance lock during rtnetlink operations")
Signed-off-by: Florian Westphal <fw@strlen.de>
Link: https://patch.msgid.link/20251013185052.14021-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: add NUMA awareness to skb_attempt_defer_free() 2025-09-30T13:45:53+00:00 Eric Dumazet edumazet@google.com 2025-09-28T08:49:34+00:00 5628f3fe3b16114e8424bbfcf0594caef8958a06 Instead of sharing sd->defer_list & sd->defer_count with many cpus, add one pair for each NUMA node. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250928084934.3266948-4-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
Instead of sharing sd->defer_list & sd->defer_count with
many cpus, add one pair for each NUMA node.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250928084934.3266948-4-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net: use llist for sd->defer_list 2025-09-30T13:45:53+00:00 Eric Dumazet edumazet@google.com 2025-09-28T08:49:33+00:00 844c9db7f7f5fe1b0b53ed9f1c2bc7313b3021c8 Get rid of sd->defer_lock and adopt llist operations. We optimize skb_attempt_defer_free() for the common case, where the packet is queued. Otherwise sd->defer_count is increasing, until skb_defer_free_flush() clears it. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250928084934.3266948-3-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
Get rid of sd->defer_lock and adopt llist operations.

We optimize skb_attempt_defer_free() for the common case,
where the packet is queued. Otherwise sd->defer_count
is increasing, until skb_defer_free_flush() clears it.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250928084934.3266948-3-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net: make softnet_data.defer_count an atomic 2025-09-30T13:45:52+00:00 Eric Dumazet edumazet@google.com 2025-09-28T08:49:32+00:00 9c94ae6bb0b2895024b6e29fcc1cbec968b4776a This is preparation work to remove the softnet_data.defer_lock, as it is contended on hosts with large number of cores. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250928084934.3266948-2-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
This is preparation work to remove the softnet_data.defer_lock,
as it is contended on hosts with large number of cores.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250928084934.3266948-2-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net: gso: restore ids of outer ip headers correctly 2025-09-25T10:42:49+00:00 Richard Gobert richardbgobert@gmail.com 2025-09-23T08:59:06+00:00 3271f19bf7b9df665549666d789b9f126b4420c7 Currently, NETIF_F_TSO_MANGLEID indicates that the inner-most ID can be mangled. Outer IDs can always be mangled. Make GSO preserve outer IDs by default, with NETIF_F_TSO_MANGLEID allowing both inner and outer IDs to be mangled. This commit also modifies a few drivers that use SKB_GSO_FIXEDID directly. Signed-off-by: Richard Gobert <richardbgobert@gmail.com> Reviewed-by: Edward Cree <ecree.xilinx@gmail.com> # for sfc Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20250923085908.4687-4-richardbgobert@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
Currently, NETIF_F_TSO_MANGLEID indicates that the inner-most ID can
be mangled. Outer IDs can always be mangled.

Make GSO preserve outer IDs by default, with NETIF_F_TSO_MANGLEID allowing
both inner and outer IDs to be mangled.

This commit also modifies a few drivers that use SKB_GSO_FIXEDID directly.

Signed-off-by: Richard Gobert <richardbgobert@gmail.com>
Reviewed-by: Edward Cree <ecree.xilinx@gmail.com> # for sfc
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250923085908.4687-4-richardbgobert@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-09-18T18:26:06+00:00 Jakub Kicinski kuba@kernel.org 2025-09-18T18:23:29+00:00 f2cdc4c22bca57ab4cdb28ef4a02c53837d26fe0 Cross-merge networking fixes after downstream PR (net-6.17-rc7). No conflicts. Adjacent changes: drivers/net/ethernet/mellanox/mlx5/core/en/fs.h 9536fbe10c9d ("net/mlx5e: Add PSP steering in local NIC RX") 7601a0a46216 ("net/mlx5e: Add a miss level for ipsec crypto offload") Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Cross-merge networking fixes after downstream PR (net-6.17-rc7).

No conflicts.

Adjacent changes:

drivers/net/ethernet/mellanox/mlx5/core/en/fs.h
  9536fbe10c9d ("net/mlx5e: Add PSP steering in local NIC RX")
  7601a0a46216 ("net/mlx5e: Add a miss level for ipsec crypto offload")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: tcp: allow tcp_timewait_sock to validate skbs before handing to device 2025-09-18T10:32:06+00:00 Daniel Zahka daniel.zahka@gmail.com 2025-09-17T00:09:34+00:00 0917bb139eed467a6376db903ad7a67981ec1420 Provide a callback to validate skb's originating from tcp timewait socks before passing to the device layer. Full socks have a sk_validate_xmit_skb member for checking that a device is capable of performing offloads required for transmitting an skb. With psp, tcp timewait socks will inherit the crypto state from their corresponding full socks. Any ACKs or RSTs that originate from a tcp timewait sock carrying psp state should be psp encapsulated. Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250917000954.859376-8-daniel.zahka@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
Provide a callback to validate skb's originating from tcp timewait
socks before passing to the device layer. Full socks have a
sk_validate_xmit_skb member for checking that a device is capable of
performing offloads required for transmitting an skb. With psp, tcp
timewait socks will inherit the crypto state from their corresponding
full socks. Any ACKs or RSTs that originate from a tcp timewait sock
carrying psp state should be psp encapsulated.

Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250917000954.859376-8-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net: move sk_validate_xmit_skb() to net/core/dev.c 2025-09-18T10:32:06+00:00 Daniel Zahka daniel.zahka@gmail.com 2025-09-17T00:09:33+00:00 8c511c1df380780b8a81050767dbfe7ca518d3a2 Move definition of sk_validate_xmit_skb() from net/core/sock.c to net/core/dev.c. This change is in preparation of the next patch, where sk_validate_xmit_skb() will need to cast sk to a tcp_timewait_sock *, and access member fields. Including linux/tcp.h from linux/sock.h creates a circular dependency, and dev.c is the only current call site of this function. Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250917000954.859376-7-daniel.zahka@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
Move definition of sk_validate_xmit_skb() from net/core/sock.c to
net/core/dev.c.

This change is in preparation of the next patch, where
sk_validate_xmit_skb() will need to cast sk to a tcp_timewait_sock *,
and access member fields. Including linux/tcp.h from linux/sock.h
creates a circular dependency, and dev.c is the only current call site
of this function.

Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250917000954.859376-7-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net: use NUMA drop counters for softnet_data.dropped 2025-09-14T18:35:17+00:00 Eric Dumazet edumazet@google.com 2025-09-09T12:19:42+00:00 fdae0ab67d57d480dc61e9fb45678bbdc3786711 Hosts under DOS attack can suffer from false sharing in enqueue_to_backlog() : atomic_inc(&sd->dropped). This is because sd->dropped can be touched from many cpus, possibly residing on different NUMA nodes. Generalize the sk_drop_counters infrastucture added in commit c51613fa276f ("net: add sk->sk_drop_counters") and use it to replace softnet_data.dropped with NUMA friendly softnet_data.drop_counters. This adds 64 bytes per cpu, maybe more in the future if we increase the number of counters (currently 2) per 'struct numa_drop_counters'. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250909121942.1202585-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Hosts under DOS attack can suffer from false sharing
in enqueue_to_backlog() : atomic_inc(&sd->dropped).

This is because sd->dropped can be touched from many cpus,
possibly residing on different NUMA nodes.

Generalize the sk_drop_counters infrastucture
added in commit c51613fa276f ("net: add sk->sk_drop_counters")
and use it to replace softnet_data.dropped
with NUMA friendly softnet_data.drop_counters.

This adds 64 bytes per cpu, maybe more in the future
if we increase the number of counters (currently 2)
per 'struct numa_drop_counters'.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250909121942.1202585-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: Use NAPI_* in test_bit when stopping napi kthread 2025-09-12T00:52:42+00:00 Samiullah Khawaja skhawaja@google.com 2025-09-10T20:37:16+00:00 247981eecd3dd6ff51bd0a0223deba8af39c5498 napi_stop_kthread waits for the NAPI_STATE_SCHED_THREADED to be unset before stopping the kthread. But it uses test_bit with the NAPIF_STATE_SCHED_THREADED and that might stop the kthread early before the flag is unset. Use the NAPI_* variant of the NAPI state bits in test_bit instead. Tested: ./tools/testing/selftests/net/nl_netdev.py TAP version 13 1..7 ok 1 nl_netdev.empty_check ok 2 nl_netdev.lo_check ok 3 nl_netdev.page_pool_check ok 4 nl_netdev.napi_list_check ok 5 nl_netdev.dev_set_threaded ok 6 nl_netdev.napi_set_threaded ok 7 nl_netdev.nsim_rxq_reset_down # Totals: pass:7 fail:0 xfail:0 xpass:0 skip:0 error:0 ./tools/testing/selftests/drivers/net/napi_threaded.py TAP version 13 1..2 ok 1 napi_threaded.change_num_queues ok 2 napi_threaded.enable_dev_threaded_disable_napi_threaded # Totals: pass:2 fail:0 xfail:0 xpass:0 skip:0 error:0 Fixes: 689883de94dd ("net: stop napi kthreads when THREADED napi is disabled") Signed-off-by: Samiullah Khawaja <skhawaja@google.com> Link: https://patch.msgid.link/20250910203716.1016546-1-skhawaja@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
napi_stop_kthread waits for the NAPI_STATE_SCHED_THREADED to be unset
before stopping the kthread. But it uses test_bit with the
NAPIF_STATE_SCHED_THREADED and that might stop the kthread early before
the flag is unset.

Use the NAPI_* variant of the NAPI state bits in test_bit instead.

Tested:
 ./tools/testing/selftests/net/nl_netdev.py
 TAP version 13
 1..7
 ok 1 nl_netdev.empty_check
 ok 2 nl_netdev.lo_check
 ok 3 nl_netdev.page_pool_check
 ok 4 nl_netdev.napi_list_check
 ok 5 nl_netdev.dev_set_threaded
 ok 6 nl_netdev.napi_set_threaded
 ok 7 nl_netdev.nsim_rxq_reset_down
 # Totals: pass:7 fail:0 xfail:0 xpass:0 skip:0 error:0

 ./tools/testing/selftests/drivers/net/napi_threaded.py
 TAP version 13
 1..2
 ok 1 napi_threaded.change_num_queues
 ok 2 napi_threaded.enable_dev_threaded_disable_napi_threaded
 # Totals: pass:2 fail:0 xfail:0 xpass:0 skip:0 error:0

Fixes: 689883de94dd ("net: stop napi kthreads when THREADED napi is disabled")
Signed-off-by: Samiullah Khawaja <skhawaja@google.com>
Link: https://patch.msgid.link/20250910203716.1016546-1-skhawaja@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>