Commit cf48f79b authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi into master 

Pull SCSI fix from James Bottomley:
 "Small core patch to fix a corner case bug: we forgot to run the queues
  to handle starvation in the error exit from the scsi_queue_rq routine,
  which can lead to hangs on error conditions"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: core: Run queue in case of I/O resource contention failure
parents 04300d66 3f0dcfbc

drivers/scsi/scsi_lib.c

+11 −5
Original line number Diff line number Diff line
@@ -547,6 +547,15 @@ static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd) 
	scsi_uninit_cmd(cmd);

}



static void scsi_run_queue_async(struct scsi_device *sdev)

{

	if (scsi_target(sdev)->single_lun ||

	    !list_empty(&sdev->host->starved_list))

		kblockd_schedule_work(&sdev->requeue_work);

	else

		blk_mq_run_hw_queues(sdev->request_queue, true);

}



/* Returns false when no more bytes to process, true if there are more */

static bool scsi_end_request(struct request *req, blk_status_t error,

		unsigned int bytes)
@@ -591,11 +600,7 @@ static bool scsi_end_request(struct request *req, blk_status_t error, 


	__blk_mq_end_request(req, error);



	if (scsi_target(sdev)->single_lun ||

	    !list_empty(&sdev->host->starved_list))

		kblockd_schedule_work(&sdev->requeue_work);

	else

		blk_mq_run_hw_queues(q, true);

	scsi_run_queue_async(sdev);



	percpu_ref_put(&q->q_usage_counter);

	return false;
@@ -1702,6 +1707,7 @@ out_put_budget: 
		 */

		if (req->rq_flags & RQF_DONTPREP)

			scsi_mq_uninit_cmd(cmd);

		scsi_run_queue_async(sdev);

		break;

	}

	return ret;

CRA Git | Maintained and supported by SUSTech CRA and CCSE