On Thu, Apr 04, 2019 at 10:08:43AM -0700, Bart Van Assche wrote: > blk_mq_try_issue_directly() can return BLK_STS*_RESOURCE for requests that > have been queued. If that happens when blk_mq_try_issue_directly() is called > by the dm-mpath driver then dm-mpath will try to resubmit a request that is > already queued and a kernel crash follows. Since it is nontrivial to fix > blk_mq_request_issue_directly(), revert the blk_mq_request_issue_directly() > changes that went into kernel v5.0. > > This patch reverts the following commits: > * d6a51a97c0b2 ("blk-mq: replace and kill blk_mq_request_issue_directly") # v5.0. > * 5b7a6f128aad ("blk-mq: issue directly with bypass 'false' in blk_mq_sched_insert_requests") # v5.0. > * 7f556a44e61d ("blk-mq: refactor the code of issue request directly") # v5.0. I am fine to revert them now. However, could you revert them one by one so that they can be reviewed easily? Thanks, Ming