Re: [PATCH for-rc 1/9] RDMA/hns: Check atomic wr length

Leon Romanovsky
2024-07-07T08:24:37Z

On Fri, Jul 05, 2024 at 04:59:29PM +0800, Junxian Huang wrote:
> 8 bytes is the only supported length of atomic. Return an error if
> it is not.
>
> Fixes: 384f88185112 ("RDMA/hns: Add atomic support")
> Signed-off-by: Junxian Huang <huangjunxian6@hisilicon.com>
> ---
> drivers/infiniband/hw/hns/hns_roce_device.h | 2 ++
> drivers/infiniband/hw/hns/hns_roce_hw_v2.c | 19 +++++++++++++++----
> 2 files changed, 17 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/infiniband/hw/hns/hns_roce_device.h b/drivers/infiniband/hw/hns/hns_roce_device.h
> index ff0b3f68ee3a..05005079258c 100644
> --- a/drivers/infiniband/hw/hns/hns_roce_device.h
> +++ b/drivers/infiniband/hw/hns/hns_roce_device.h
> @@ -91,6 +91,8 @@
> /* Configure to HW for PAGE_SIZE larger than 4KB */
> #define PG_SHIFT_OFFSET (PAGE_SHIFT - 12)
>
> +#define ATOMIC_WR_LEN 8
> +
> #define HNS_ROCE_IDX_QUE_ENTRY_SZ 4
> #define SRQ_DB_REG 0x230
>
> diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
> index 4287818a737f..a5d746a5cc68 100644
> --- a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
> +++ b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
> @@ -164,15 +164,23 @@ static void set_frmr_seg(struct hns_roce_v2_rc_send_wqe *rc_sq_wqe,
> hr_reg_clear(fseg, FRMR_BLK_MODE);
> }
>
> -static void set_atomic_seg(const struct ib_send_wr *wr,
> - struct hns_roce_v2_rc_send_wqe *rc_sq_wqe,
> - unsigned int valid_num_sge)
> +static int set_atomic_seg(struct hns_roce_dev *hr_dev,
> + const struct ib_send_wr *wr,
> + struct hns_roce_v2_rc_send_wqe *rc_sq_wqe,
> + unsigned int valid_num_sge, u32 msg_len)
> {
> struct hns_roce_v2_wqe_data_seg *dseg =
> (void *)rc_sq_wqe + sizeof(struct hns_roce_v2_rc_send_wqe);
> struct hns_roce_wqe_atomic_seg *aseg =
> (void *)dseg + sizeof(struct hns_roce_v2_wqe_data_seg);
>
> + if (msg_len != ATOMIC_WR_LEN) {
> + ibdev_err_ratelimited(&hr_dev->ib_dev,
> + "invalid atomic wr len, len = %u.\n",
> + msg_len);
> + return -EINVAL;

1. Please don't add prints in data-path.
2. You most likely need to add this check before calling to set_atomic_seg().
3. You shouldn't continue to process the WQE if the length is invalid.
Need to return from set_rc_wqe() and not continue.
4. I wonder if it is right place to put this limitation and can't be
enforced much earlier.

Thanks