If a completion occurs after blk_mq_rq_timed_out() has reset
rq->aborted_gstate and the request is again in flight when the timeout
expires then a request will be completed twice: a first time by the
timeout handler and a second time when the regular completion occurs.
Additionally, the blk-mq timeout handling code ignores completions that
occur after blk_mq_check_expired() has been called and before
blk_mq_rq_timed_out() has reset rq->aborted_gstate. If a block driver
timeout handler always returns BLK_EH_RESET_TIMER then the result will
be that the request never terminates.
OK, now I understand how we can complete twice. Israel, can you verify
this patch solves your double completion problem?
Given that it is, the change log of your patches should be modified to
the original bug report it solves.
Thread starts here:
http://lists.infradead.org/pipermail/linux-nvme/2018-February/015848.html
