On Mon, Jul 14, 2025 at 08:39:42AM +0300, Tariq Toukan wrote:
> From: Leon Romanovsky <leonro@nvidia.com>
>
> qdisc_sleeping variable is declared as "struct Qdisc __rcu" and
> as such needs proper annotation while accessing it.
>
> Without rtnl_dereference(), the following error is generated by sparse:
>
> drivers/net/ethernet/mellanox/mlx5/core/en/qos.c:377:40: warning:
> incorrect type in initializer (different address spaces)
> drivers/net/ethernet/mellanox/mlx5/core/en/qos.c:377:40: expected
> struct Qdisc *qdisc
> drivers/net/ethernet/mellanox/mlx5/core/en/qos.c:377:40: got struct
> Qdisc [noderef] __rcu *qdisc_sleeping
>
> Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
> Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
> ---
> drivers/net/ethernet/mellanox/mlx5/core/en/qos.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/qos.c b/drivers/net/ethernet/mellanox/mlx5/core/en/qos.c
> index f0744a45db92..4e461cb03b83 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en/qos.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/qos.c
> @@ -374,7 +374,7 @@ void mlx5e_reactivate_qos_sq(struct mlx5e_priv *priv, u16 qid, struct netdev_que
> void mlx5e_reset_qdisc(struct net_device *dev, u16 qid)
> {
> struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, qid);
> - struct Qdisc *qdisc = dev_queue->qdisc_sleeping;
> + struct Qdisc *qdisc = rtnl_dereference(dev_queue->qdisc_sleeping);
>
> if (!qdisc)
> return;
Good catch, other acesses to the qdisc_sleeping are fine.
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
> --
> 2.40.1