Re: [dpdk-dev] [PATCH] net/hns3: fix mailbox communication with HW

["Min Hu (Connor)" <humin29@huawei.com>]

Hi, Thomos, Ferruh,
	As this patch is to fix a critical bug for hns3 PMD, we hope this patch 
could be merged into 21.11.
	Please check it out. Thanks.


在 2021/10/28 19:52, Min Hu (Connor) 写道:
> Mailbox is the communication mechanism between SW and HW. There exist two
> approaches for SW to recongnize mailbox message from HW. One way is using
> match_id, the other is to compare the message code. The two approaches are
> independent and used in different scenarios.
> 
> But for the second approache, "next_to_use" should be updated and written
> to HW register. If it not done, HW do not know the position SW steps, then,
> the communication between SW and HW will turn to be failed.
> 
> Fixes: dbbbad23e380 ("net/hns3: fix VF handling LSC event in secondary process")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Min Hu (Connor) <humin29@huawei.com>
> ---
>   drivers/net/hns3/hns3_mbx.c | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/net/hns3/hns3_mbx.c b/drivers/net/hns3/hns3_mbx.c
> index a47622b8a6..245652e2ed 100644
> --- a/drivers/net/hns3/hns3_mbx.c
> +++ b/drivers/net/hns3/hns3_mbx.c
> @@ -435,6 +435,9 @@ hns3_handle_mbx_msg_out_intr(struct hns3_hw *hw)
>   scan_next:
>   		next_to_use = (next_to_use + 1) % hw->cmq.crq.desc_num;
>   	}
> +
> +	crq->next_to_use = next_to_use;
> +	hns3_write_dev(hw, HNS3_CMDQ_RX_HEAD_REG, crq->next_to_use);
>   }
>   
>   void
>