Re: [PATCH net-next] net/mlx5e: Fix error handling in RQ memory model registration

["yanjun.zhu" <yanjun.zhu@linux.dev>]

On 6/24/25 7:07 AM, Fushuai Wang wrote:
> Currently when xdp_rxq_info_reg_mem_model() fails in the XSK path, the
> error handling incorrectly jumps to err_destroy_page_pool. While this
> may not cause errors, we should make it jump to the correct location.

In the page_pool_destroy function, if pool is NULL, the function will 
simply return, so the goto err_destroy_page_pool statement will not lead 
to any issues.

However, this commit does improve the clarity of the logic.

Looks good to me.

void page_pool_destroy(struct page_pool *pool)
{
         if (!pool)
                 return;

         if (!page_pool_put(pool))
                 return;

         page_pool_disable_direct_recycling(pool);
         page_pool_free_frag(pool);

         if (!page_pool_release(pool))
                 return;

         page_pool_detached(pool);
         pool->defer_start = jiffies;
         pool->defer_warn  = jiffies + DEFER_WARN_INTERVAL;

         INIT_DELAYED_WORK(&pool->release_dw, page_pool_release_retry);
         schedule_delayed_work(&pool->release_dw, DEFER_TIME);
}

Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev>

Zhu Yanjun

> 
> Signed-off-by: Fushuai Wang <wangfushuai@baidu.com>
> ---
>   drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 9 ++++++---
>   1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> index ea822c69d137..1e3ba51b7995 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
> @@ -915,6 +915,8 @@ static int mlx5e_alloc_rq(struct mlx5e_params *params,
>   	if (xsk) {
>   		err = xdp_rxq_info_reg_mem_model(&rq->xdp_rxq,
>   						 MEM_TYPE_XSK_BUFF_POOL, NULL);
> +		if (err)
> +			goto err_free_by_rq_type;
>   		xsk_pool_set_rxq_info(rq->xsk_pool, &rq->xdp_rxq);
>   	} else {
>   		/* Create a page_pool and register it with rxq */
> @@ -941,12 +943,13 @@ static int mlx5e_alloc_rq(struct mlx5e_params *params,
>   			rq->page_pool = NULL;
>   			goto err_free_by_rq_type;
>   		}
> -		if (xdp_rxq_info_is_reg(&rq->xdp_rxq))
> +		if (xdp_rxq_info_is_reg(&rq->xdp_rxq)) {
>   			err = xdp_rxq_info_reg_mem_model(&rq->xdp_rxq,
>   							 MEM_TYPE_PAGE_POOL, rq->page_pool);
> +			if (err)
> +				goto err_destroy_page_pool;
> +		}
>   	}
> -	if (err)
> -		goto err_destroy_page_pool;
>   
>   	for (i = 0; i < wq_sz; i++) {
>   		if (rq->wq_type == MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ) {