[PATCH 3.12 043/101] scsi: only re-lock door after EH on devices that were reset

From: Jiri Slaby
Date: Wed Dec 03 2014 - 06:55:26 EST

From: Christoph Hellwig <hch@xxxxxx>

3.12-stable review patch. If anyone has any objections, please let me know.


commit 48379270fe6808cf4612ee094adc8da2b7a83baa upstream.

Setups that use the blk-mq I/O path can lock up if a host with a single
device that has its door locked enters EH. Make sure to only send the
command to re-lock the door to devices that actually were reset and thus
might have lost their state. Otherwise the EH code might be get blocked
on blk_get_request as all requests for non-reset devices might be in use.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reported-by: Meelis Roos <meelis.roos@xxxxx>
Tested-by: Meelis Roos <meelis.roos@xxxxx>
Reviewed-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
drivers/scsi/scsi_error.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 9ba3642cb19e..066e3198838d 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -1746,8 +1746,10 @@ static void scsi_restart_operations(struct Scsi_Host *shost)
* is no point trying to lock the door of an off-line device.
shost_for_each_device(sdev, shost) {
- if (scsi_device_online(sdev) && sdev->locked)
+ if (scsi_device_online(sdev) && sdev->was_reset && sdev->locked) {
+ sdev->was_reset = 0;
+ }


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