Re: [PATCH net 2/2] net/mlx5e: Avoid unregistering PSP twice

[Simon Horman]

On Mon, Dec 01, 2025 at 05:13:28PM +0200, Tariq Toukan wrote:
> From: Cosmin Ratiu <cratiu@xxxxxxxxxx>
> 
> PSP is unregistered twice in:
> _mlx5e_remove -> mlx5e_psp_unregister
> mlx5e_nic_cleanup -> mlx5e_psp_unregister
> 
> This leads to a refcount underflow in some conditions:
> ------------[ cut here ]------------
> refcount_t: underflow; use-after-free.
> WARNING: CPU: 2 PID: 1694 at lib/refcount.c:28 refcount_warn_saturate+0xd8/0xe0
> [...]
>  mlx5e_psp_unregister+0x26/0x50 [mlx5_core]
>  mlx5e_nic_cleanup+0x26/0x90 [mlx5_core]
>  mlx5e_remove+0xe6/0x1f0 [mlx5_core]
>  auxiliary_bus_remove+0x18/0x30
>  device_release_driver_internal+0x194/0x1f0
>  bus_remove_device+0xc6/0x130
>  device_del+0x159/0x3c0
>  mlx5_rescan_drivers_locked+0xbc/0x2a0 [mlx5_core]
> [...]
> 
> Do not directly remove psp from the _mlx5e_remove path, the PSP cleanup
> happens as part of profile cleanup.
> 
> Fixes: 89ee2d92f66c ("net/mlx5e: Support PSP offload functionality")
> Signed-off-by: Cosmin Ratiu <cratiu@xxxxxxxxxx>
> Reviewed-by: Dragos Tatulea <dtatulea@xxxxxxxxxx>
> Signed-off-by: Tariq Toukan <tariqt@xxxxxxxxxx>

Reviewed-by: Simon Horman <horms@xxxxxxxxxx>