[PATCH 3.16 053/306] scsi: ibmvfc: Fix I/O hang when port is not mapped

From: Ben Hutchings
Date: Wed Feb 15 2017 - 18:43:15 EST

3.16.40-rc1 review patch. If anyone has any objections, please let me know.


From: Brian King <brking@xxxxxxxxxxxxxxxxxx>

commit 07d0e9a847401ffd2f09bd450d41644cd090e81d upstream.

If a VFC port gets unmapped in the VIOS, it may not respond with a CRQ
init complete following H_REG_CRQ. If this occurs, we can end up having
called scsi_block_requests and not a resulting unblock until the init
complete happens, which may never occur, and we end up hanging I/O
requests. This patch ensures the host action stay set to
IBMVFC_HOST_ACTION_TGT_DEL so we move all rports into devloss state and
unblock unless we receive an init complete.

Signed-off-by: Brian King <brking@xxxxxxxxxxxxxxxxxx>
Acked-by: Tyrel Datwyler <tyreld@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
drivers/scsi/ibmvscsi/ibmvfc.c | 1 -
1 file changed, 1 deletion(-)

--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -717,7 +717,6 @@ static int ibmvfc_reset_crq(struct ibmvf
spin_lock_irqsave(vhost->host->host_lock, flags);
vhost->state = IBMVFC_NO_CRQ;
vhost->logged_in = 0;
- ibmvfc_set_host_action(vhost, IBMVFC_HOST_ACTION_NONE);

/* Clean out the queue */
memset(crq->msgs, 0, PAGE_SIZE);