[PATCH 0/3] avoid race between time out and tear down

[Sagi Grimberg]

>>>>> Avoid race between time out and tear down for rdma and tcp.
>>>>
>>>> This patchset overall looks good, but we still need the patch that
>>>> avoids double completion:
>>>>
>>>> -- 
>>>> diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
>>>> index 629b025685d1..46428ff0b0fc 100644
>>>> --- a/drivers/nvme/host/tcp.c
>>>> +++ b/drivers/nvme/host/tcp.c
>>>> @@ -2175,7 +2175,7 @@ static void nvme_tcp_complete_timed_out(struct 
>>>> request *rq)
>>>>          /* fence other contexts that may complete the command */
>>>>          mutex_lock(&to_tcp_ctrl(ctrl)->teardown_lock);
>>>>          nvme_tcp_stop_queue(ctrl, nvme_tcp_queue_id(req->queue));
>>>> -       if (!blk_mq_request_completed(rq)) {
>>>> +       if (blk_mq_request_started(rq) && 
>>>> !blk_mq_request_completed(rq)) {
>>> Yes, this patch is need. and samely for nvme_cancel_request.
>>> This will fix the race with asynchronous completion.
>>>
>>> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
>>> index e85f6304efd7..1e838d952096 100644
>>> --- a/drivers/nvme/host/core.c
>>> +++ b/drivers/nvme/host/core.c
>>> @@ -338,7 +338,7 @@ bool nvme_cancel_request(struct request *req, 
>>> void *data, bool reserved)
>>>                                  "Cancelling I/O %d", req->tag);
>>>
>>>          /* don't abort one completed request */
>>> -       if (blk_mq_request_completed(req))
>>> +       if (blk_mq_request_completed(req) || 
>>> !blk_mq_request_started(rq))
>>>                  return true;
>>>
>>>          nvme_req(req)->status = NVME_SC_HOST_ABORTED_CMD;
>>
>> This one is unneeded because blk_mq_tagset_busy_iter checks that the
>> request has started...
> Yes, it is already checked.

Can you add the attached patches and resend?

You can also add my:
Reviewed-by: Sagi Grimberg <sagi at grimberg.me>
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