This is a note to let you know that I've just added the patch titled scsi: avoid a permanent stop of the scsi device's request queue to the 4.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: scsi-avoid-a-permanent-stop-of-the-scsi-device-s-request-queue.patch and it can be found in the queue-4.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From d2a145252c52792bc59e4767b486b26c430af4bb Mon Sep 17 00:00:00 2001 From: Wei Fang <fangwei1@xxxxxxxxxx> Date: Tue, 13 Dec 2016 09:25:21 +0800 Subject: scsi: avoid a permanent stop of the scsi device's request queue From: Wei Fang <fangwei1@xxxxxxxxxx> 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@xxxxxxxxxx> Signed-off-by: Wei Fang <fangwei1@xxxxxxxxxx> Reviewed-by: Ewan D. Milne <emilne@xxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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; Patches currently in stable-queue which might be from fangwei1@xxxxxxxxxx are queue-4.8/scsi-avoid-a-permanent-stop-of-the-scsi-device-s-request-queue.patch queue-4.8/block-protect-iterate_bdevs-against-concurrent-close.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html