From: Hannes Reinecke <hare@suse.de>
Date: Fri, 17 Jun 2016 10:00:56 +0200
Subject: [PATCH] scsi: do not print 'reservation conflict' for TEST UNIT READY
Patch-Mainline: submitted linux-scsi 2016/09/12
References: bsc#1027054, bsc#1082587

SPC-2 and SPC-3 (or later) differ in the handling of reservation
conflict for TEST UNIT READY. SPC-2 will return 'reservation conflict',
whereas SPC-3 will return GOOD status.
On a mixed system with both SPC-2 and SPC-3 targets one will
see lots of 'reservation conflict' messages from eg multipath
path checkers, which in fact just signal normal operation.
So we should not be printing out 'reservation conflict' for
TEST UNIT READY responses.

Signed-off-by: Hannes Reinecke <hare@suse.com>
---
 drivers/scsi/scsi_error.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -1976,8 +1976,11 @@ int scsi_decide_disposition(struct scsi_
 		return SUCCESS;
 
 	case RESERVATION_CONFLICT:
-		sdev_printk(KERN_INFO, scmd->device,
-			    "reservation conflict\n");
+		if (scmd->cmnd[0] != TEST_UNIT_READY)
+			sdev_printk(KERN_INFO, scmd->device,
+				    "reservation conflict\n");
+		else
+			scmd->request->rq_flags |= RQF_QUIET;
 		set_host_byte(scmd, DID_NEXUS_FAILURE);
 		return SUCCESS; /* causes immediate i/o error */
 	default: