| From | Greg Kroah-Hartman <> | Subject | [PATCH 4.8 48/96] scsi: avoid a permanent stop of the scsi devices request queue | Date | Fri, 6 Jan 2017 22:43:36 +0100 |
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4.8-stable review patch. If anyone has any objections, please let me know.
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From: Wei Fang <fangwei1@huawei.com>
commit d2a145252c52792bc59e4767b486b26c430af4bb upstream.
A race between scanning and fc_remote_port_delete() may result in a permanent stop if the device gets blocked before scsi_sysfs_add_sdev() and unblocked after. The reason is that blocking a device sets both the SDEV_BLOCKED state and the QUEUE_FLAG_STOPPED. However, scsi_sysfs_add_sdev() unconditionally sets SDEV_RUNNING which causes the device to be ignored by scsi_target_unblock() and thus never have its QUEUE_FLAG_STOPPED cleared leading to a device which is apparently running but has a stopped queue.
We actually have two places where SDEV_RUNNING is set: once in scsi_add_lun() which respects the blocked flag and once in scsi_sysfs_add_sdev() which doesn't. Since the second set is entirely spurious, simply remove it to fix the problem.
Reported-by: Zengxi Chen <chenzengxi@huawei.com> Signed-off-by: Wei Fang <fangwei1@huawei.com> Reviewed-by: Ewan D. Milne <emilne@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- drivers/scsi/scsi_sysfs.c | 4 ---- 1 file changed, 4 deletions(-)
--- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -1204,10 +1204,6 @@ int scsi_sysfs_add_sdev(struct scsi_devi struct request_queue *rq = sdev->request_queue; struct scsi_target *starget = sdev->sdev_target; - error = scsi_device_set_state(sdev, SDEV_RUNNING); - if (error) - return error; - error = scsi_target_add(starget); if (error) return error;
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