Re: [PATCH] nvme: donot try to resubmit a canceled IO

[brookxu <brookxu.cn@gmail.com>]

Hi all:

Sorry to make noise, please ignore this patch.

Thanks.

在 2023/5/11 18:20, Chunguang Xu 写道:
> From: "chunguang.xu" <chunguang.xu@shopee.com>
>
> Now if NVMe over rdma and NVMe over TCP module detected
> controller is INACTIVE on the IO timeout path, it will
> try to call nvmf_complete_timed_out_request() to
> terminated this IO. But nvme_complete_rq() will continue
> to retry this IO, as the request_queue is quiescing at
> this time, if the target cannot connected or the host
> actively executes disconnect, it will cause this IO hang
> in the hctx dispatch queue and cannot be processed,
> resulting in hung task, the calltrace as followed:
>
> [ 1575.570245] INFO: task kworker/u129:6:758 blocked for more than 966 seconds.
> [ 1575.577829]       Tainted: G           OE     5.4.0-77-shopee-generic #86+5
> [ 1575.585323] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [ 1575.593670] kworker/u129:6  D    0   758      2 0x80004000
> [ 1575.593681] Workqueue: nvme-wq nvme_scan_work [nvme_core]
> [ 1575.593683] Call Trace:
> [ 1575.593689]  __schedule+0x2ee/0x750
> [ 1575.593691]  schedule+0x42/0xb0
> [ 1575.593693]  io_schedule+0x16/0x40
> [ 1575.593696]  do_read_cache_page+0x438/0x840
> [ 1575.593698]  ? __switch_to_asm+0x40/0x70
> [ 1575.593700]  ? file_fdatawait_range+0x30/0x30
> [ 1575.593702]  read_cache_page+0x12/0x20
> [ 1575.593704]  read_dev_sector+0x27/0xd0
> [ 1575.593705]  read_lba+0xbd/0x220
> [ 1575.593707]  ? kmem_cache_alloc_trace+0x1b0/0x240
> [ 1575.593708]  efi_partition+0x1e0/0x700
> [ 1575.593710]  ? vsnprintf+0x39e/0x4e0
> [ 1575.593712]  ? snprintf+0x49/0x60
> [ 1575.593714]  check_partition+0x154/0x250
> [ 1575.593715]  rescan_partitions+0xae/0x280
> [ 1575.593718]  bdev_disk_changed+0x5f/0x70
> [ 1575.593719]  __blkdev_get+0x3e3/0x550
> [ 1575.593720]  blkdev_get+0x3d/0x150
> [ 1575.593722]  __device_add_disk+0x329/0x480
> [ 1575.593723]  device_add_disk+0x13/0x20
> [ 1575.593727]  nvme_mpath_set_live+0x125/0x130 [nvme_core]
> [ 1575.593731]  nvme_mpath_add_disk+0x11e/0x130 [nvme_core]
> [ 1575.593734]  nvme_validate_ns+0x6a8/0x9d0 [nvme_core]
> [ 1575.593736]  ? __switch_to_asm+0x40/0x70
> [ 1575.593739]  nvme_scan_work+0x1e0/0x350 [nvme_core]
> [ 1575.593743]  process_one_work+0x1eb/0x3b0
> [ 1575.593745]  worker_thread+0x4d/0x400
> [ 1575.593747]  kthread+0x104/0x140
> [ 1575.593748]  ? process_one_work+0x3b0/0x3b0
> [ 1575.593750]  ? kthread_park+0x90/0x90
> [ 1575.593751]  ret_from_fork+0x1f/0x40
>
> This issue seems not fixed on lastes kernel, try to fix it here.
>
> Signed-off-by: chunguang.xu <chunguang.xu@shopee.com>
> ---
>   drivers/nvme/host/core.c    | 3 +++
>   drivers/nvme/host/fabrics.h | 1 +
>   2 files changed, 4 insertions(+)
>
> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> index ccb6eb1282f8..bf9273081595 100644
> --- a/drivers/nvme/host/core.c
> +++ b/drivers/nvme/host/core.c
> @@ -349,6 +349,9 @@ static inline enum nvme_disposition nvme_decide_disposition(struct request *req)
>   	if (likely(nvme_req(req)->status == 0))
>   		return COMPLETE;
>   
> +	if (nvme_req(req)->flags & NVME_REQ_CANCELLED)
> +		return COMPLETE;
> +
>   	if ((nvme_req(req)->status & 0x7ff) == NVME_SC_AUTH_REQUIRED)
>   		return AUTHENTICATE;
>   
> diff --git a/drivers/nvme/host/fabrics.h b/drivers/nvme/host/fabrics.h
> index dcac3df8a5f7..40a5d6659af0 100644
> --- a/drivers/nvme/host/fabrics.h
> +++ b/drivers/nvme/host/fabrics.h
> @@ -199,6 +199,7 @@ static inline void nvmf_complete_timed_out_request(struct request *rq)
>   {
>   	if (blk_mq_request_started(rq) && !blk_mq_request_completed(rq)) {
>   		nvme_req(rq)->status = NVME_SC_HOST_ABORTED_CMD;
> +		nvme_req(rq)->flags |= NVME_REQ_CANCELLED;
>   		blk_mq_complete_request(rq);
>   	}
>   }