net/mlx5e: Fix incorrect access of RCU-protected xdp_prog

rq->xdp_prog is RCU-protected and should be accessed only with
rcu_access_pointer for the NULL check in mlx5e_poll_rx_cq.

rq->xdp_prog may change on the fly only from one non-NULL value to
another non-NULL value, so the checks in mlx5e_xdp_handle and
mlx5e_poll_rx_cq will have the same result during one NAPI cycle,
meaning that no additional synchronization is needed.

Fixes: fe45386a20 ("net/mlx5e: Use RCU to protect rq->xdp_prog")
Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
This commit is contained in:
Maxim Mikityanskiy 2020-10-22 12:49:51 +03:00 committed by Saeed Mahameed
parent c5eb51adf0
commit 1a50cf9a67
1 changed files with 1 additions and 1 deletions

View File

@ -1584,7 +1584,7 @@ int mlx5e_poll_rx_cq(struct mlx5e_cq *cq, int budget)
} while ((++work_done < budget) && (cqe = mlx5_cqwq_get_cqe(cqwq)));
out:
if (rq->xdp_prog)
if (rcu_access_pointer(rq->xdp_prog))
mlx5e_xdp_rx_poll_complete(rq);
mlx5_cqwq_update_db_record(cqwq);