6.11-stable review patch. If anyone has any objections, please let me know.
------------------
From: Cosmin Ratiu <cratiu@xxxxxxxxxx>
[ Upstream commit 4dbc1d1a9f39c3711ad2a40addca04d07d9ab5d0 ]
When profile rollback fails in mlx5e_netdev_change_profile, the netdev
profile var is left set to NULL. Avoid a crash when unloading the driver
by not calling profile->cleanup in such a case.
This was encountered while testing, with the original trigger that
the wq rescuer thread creation got interrupted (presumably due to
Ctrl+C-ing modprobe), which gets converted to ENOMEM (-12) by
mlx5e_priv_init, the profile rollback also fails for the same reason
(signal still active) so the profile is left as NULL, leading to a crash
later in _mlx5e_remove.
[ 732.473932] mlx5_core 0000:08:00.1: E-Switch: Unload vfs: mode(OFFLOADS), nvfs(2), necvfs(0), active vports(2)
[ 734.525513] workqueue: Failed to create a rescuer kthread for wq "mlx5e": -EINTR
[ 734.557372] mlx5_core 0000:08:00.1: mlx5e_netdev_init_profile:6235:(pid 6086): mlx5e_priv_init failed, err=-12
[ 734.559187] mlx5_core 0000:08:00.1 eth3: mlx5e_netdev_change_profile: new profile init failed, -12
[ 734.560153] workqueue: Failed to create a rescuer kthread for wq "mlx5e": -EINTR
[ 734.589378] mlx5_core 0000:08:00.1: mlx5e_netdev_init_profile:6235:(pid 6086): mlx5e_priv_init failed, err=-12
[ 734.591136] mlx5_core 0000:08:00.1 eth3: mlx5e_netdev_change_profile: failed to rollback to orig profile, -12
[ 745.537492] BUG: kernel NULL pointer dereference, address: 0000000000000008
[ 745.538222] #PF: supervisor read access in kernel mode
<snipped>
[ 745.551290] Call Trace:
[ 745.551590] <TASK>
[ 745.551866] ? __die+0x20/0x60
[ 745.552218] ? page_fault_oops+0x150/0x400
[ 745.555307] ? exc_page_fault+0x79/0x240
[ 745.555729] ? asm_exc_page_fault+0x22/0x30
[ 745.556166] ? mlx5e_remove+0x6b/0xb0 [mlx5_core]
[ 745.556698] auxiliary_bus_remove+0x18/0x30
[ 745.557134] device_release_driver_internal+0x1df/0x240
[ 745.557654] bus_remove_device+0xd7/0x140
[ 745.558075] device_del+0x15b/0x3c0
[ 745.558456] mlx5_rescan_drivers_locked.part.0+0xb1/0x2f0 [mlx5_core]
[ 745.559112] mlx5_unregister_device+0x34/0x50 [mlx5_core]
[ 745.559686] mlx5_uninit_one+0x46/0xf0 [mlx5_core]
[ 745.560203] remove_one+0x4e/0xd0 [mlx5_core]
[ 745.560694] pci_device_remove+0x39/0xa0
[ 745.561112] device_release_driver_internal+0x1df/0x240
[ 745.561631] driver_detach+0x47/0x90
[ 745.562022] bus_remove_driver+0x84/0x100
[ 745.562444] pci_unregister_driver+0x3b/0x90
[ 745.562890] mlx5_cleanup+0xc/0x1b [mlx5_core]
[ 745.563415] __x64_sys_delete_module+0x14d/0x2f0
[ 745.563886] ? kmem_cache_free+0x1b0/0x460
[ 745.564313] ? lockdep_hardirqs_on_prepare+0xe2/0x190
[ 745.564825] do_syscall_64+0x6d/0x140
[ 745.565223] entry_SYSCALL_64_after_hwframe+0x4b/0x53
[ 745.565725] RIP: 0033:0x7f1579b1288b
Fixes: 3ef14e463f6e ("net/mlx5e: Separate between netdev objects and mlx5e profiles initialization")
Signed-off-by: Cosmin Ratiu <cratiu@xxxxxxxxxx>
Reviewed-by: Dragos Tatulea <dtatulea@xxxxxxxxxx>
Signed-off-by: Tariq Toukan <tariqt@xxxxxxxxxx>
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 16b67c457b605..3e11c1c6d4f69 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -6508,7 +6508,9 @@ static void _mlx5e_remove(struct auxiliary_device *adev)
mlx5e_dcbnl_delete_app(priv);
unregister_netdev(priv->netdev);
_mlx5e_suspend(adev, false);
- priv->profile->cleanup(priv);
+ /* Avoid cleanup if profile rollback failed. */
+ if (priv->profile)
+ priv->profile->cleanup(priv);
mlx5e_destroy_netdev(priv);
mlx5e_devlink_port_unregister(mlx5e_dev);
mlx5e_destroy_devlink(mlx5e_dev);
--
2.43.0
