Re: [PATCH] RDMA/mlx4: Remove unnessesary check in mlx4_ib_modify_wq()

From: Leon Romanovsky
Date: Sun May 09 2021 - 05:40:33 EST


On Fri, May 07, 2021 at 06:22:41PM +0800, Jiapeng Chong wrote:
> cur_state and new_state are enums and when GCC considers
> them as unsigned, the conditions are never met.
>
> Clean up the following smatch warning:
>
> drivers/infiniband/hw/mlx4/qp.c:4258 mlx4_ib_modify_wq() warn: unsigned
> 'cur_state' is never less than zero.
>
> Reported-by: Abaci Robot <abaci@xxxxxxxxxxxxxxxxx>
> Signed-off-by: Jiapeng Chong <jiapeng.chong@xxxxxxxxxxxxxxxxx>
> ---
> drivers/infiniband/hw/mlx4/qp.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/infiniband/hw/mlx4/qp.c b/drivers/infiniband/hw/mlx4/qp.c
> index 92ddbcc..162aa59 100644
> --- a/drivers/infiniband/hw/mlx4/qp.c
> +++ b/drivers/infiniband/hw/mlx4/qp.c
> @@ -4255,8 +4255,7 @@ int mlx4_ib_modify_wq(struct ib_wq *ibwq, struct ib_wq_attr *wq_attr,
> ibwq->state;
> new_state = wq_attr_mask & IB_WQ_STATE ? wq_attr->wq_state : cur_state;
>
> - if (cur_state < IB_WQS_RESET || cur_state > IB_WQS_ERR ||
> - new_state < IB_WQS_RESET || new_state > IB_WQS_ERR)
> + if (cur_state > IB_WQS_ERR || new_state > IB_WQS_ERR)
> return -EINVAL;

Actually the more robust change will be to move this change to the ib_uverbs_ex_modify_wq().

Thanks

>
> if ((new_state == IB_WQS_RDY) && (cur_state == IB_WQS_ERR))
> --
> 1.8.3.1
>