Jiri Pirko e93c9378e3 devlink: change per-devlink netdev notifier to static one ... The commit 565b4824c3 ("devlink: change port event netdev notifier from per-net to global") changed original per-net notifier to be per-devlink instance. That fixed the issue of non-receiving events of netdev uninit if that moved to a different namespace. That worked fine in -net tree. However, later on when commit ee75f1fc44 ("net/mlx5e: Create separate devlink instance for ethernet auxiliary device") and commit 72ed5d5624 ("net/mlx5: Suspend auxiliary devices only in case of PCI device suspend") were merged, a deadlock was introduced when removing a namespace with devlink instance with another nested instance. Here there is the bad flow example resulting in deadlock with mlx5: net_cleanup_work -> cleanup_net (takes down_read(&pernet_ops_rwsem) -> devlink_pernet_pre_exit() -> devlink_reload() -> mlx5_devlink_reload_down() -> mlx5_unload_one_devl_locked() -> mlx5_detach_device() -> del_adev() -> mlx5e_remove() -> mlx5e_destroy_devlink() -> devlink_free() -> unregister_netdevice_notifier() (takes down_write(&pernet_ops_rwsem) Steps to reproduce: $ modprobe mlx5_core $ ip netns add ns1 $ devlink dev reload pci/0000:08:00.0 netns ns1 $ ip netns del ns1 Resolve this by converting the notifier from per-devlink instance to a static one registered during init phase and leaving it registered forever. Use this notifier for all devlink port instances created later on. Note what a tree needs this fix only in case all of the cited fixes commits are present. Reported-by: Moshe Shemesh <moshe@nvidia.com> Fixes: 565b4824c3 ("devlink: change port event netdev notifier from per-net to global") Fixes: ee75f1fc44 ("net/mlx5e: Create separate devlink instance for ethernet auxiliary device") Fixes: 72ed5d5624 ("net/mlx5: Suspend auxiliary devices only in case of PCI device suspend") Signed-off-by: Jiri Pirko <jiri@nvidia.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Link: https://lore.kernel.org/r/20230510144621.932017-1-jiri@resnulli.us Signed-off-by: Jakub Kicinski <kuba@kernel.org>		2023-05-11 18:06:50 -07:00
..
core.c	devlink: change per-devlink netdev notifier to static one	2023-05-11 18:06:50 -07:00
dev.c
devl_internal.h	devlink: change per-devlink netdev notifier to static one	2023-05-11 18:06:50 -07:00
health.c
leftover.c	devlink: change per-devlink netdev notifier to static one	2023-05-11 18:06:50 -07:00
Makefile
netlink.c