linux-kernel - blk-mq timeout question

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Date:   Fri, 7 Jul 2017 15:45:44 +0200
From:   Stefan Haberland <sth@...ux.vnet.ibm.com>
To:     axboe@...com
Cc:     linux-kernel@...r.kernel.org
Subject: blk-mq timeout question

While changing the DASD device driver to use the blk-mq interfaces I 
found the following unexpected behavior:

In case of a timeout our complete callback is never called. Here is the 
sequence of events as I understood:

- timeout occurs
- blk_mq_check_expired() calls and checks blk_mark_rq_complete()
- our .timeout callback is called which returns BLK_EH_NOT_HANDLED and 
schedules delayed work
- our worker calls blk_mq_complete_request()
- this also checks blk_mark_rq_complete() and therefore never calls our 
complete callback

Question:
Should blk_clear_rq_complete() also be called for the BLK_EH_NOT_HANDLED 
case?

Regards,
Stefan