From 09dd15e0d9547ca424de4043bcd429bab6f285c8 Mon Sep 17 00:00:00 2001
From: Brian King <brking@linux.vnet.ibm.com>
Date: Wed, 14 Mar 2018 17:13:39 -0500
Subject: [PATCH] scsi: ibmvfc: Avoid unnecessary port relogin
References: bsc#1085404
Patch-mainline: v4.16
Git-commit: 09dd15e0d9547ca424de4043bcd429bab6f285c8
Following an RSCN, ibmvfc will issue an ADISC to determine if the
underlying target has changed, comparing the SCSI ID, WWPN, and WWNN to
determine how to handle the rport in discovery. However, the comparison
of the WWPN and WWNN was performing a memcmp between a big endian field
against a CPU endian field, which resulted in the wrong answer on LE
systems. This was observed as unexpected errors getting logged at boot
time as targets were getting relogins when not needed.
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
drivers/scsi/ibmvscsi/ibmvfc.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
index b1b1d3a3b173..daefe8172b04 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -3579,11 +3579,9 @@ static void ibmvfc_tgt_implicit_logout(struct ibmvfc_target *tgt)
static int ibmvfc_adisc_needs_plogi(struct ibmvfc_passthru_mad *mad,
struct ibmvfc_target *tgt)
{
- if (memcmp(&mad->fc_iu.response[2], &tgt->ids.port_name,
- sizeof(tgt->ids.port_name)))
+ if (wwn_to_u64((u8 *)&mad->fc_iu.response[2]) != tgt->ids.port_name)
return 1;
- if (memcmp(&mad->fc_iu.response[4], &tgt->ids.node_name,
- sizeof(tgt->ids.node_name)))
+ if (wwn_to_u64((u8 *)&mad->fc_iu.response[4]) != tgt->ids.node_name)
return 1;
if (be32_to_cpu(mad->fc_iu.response[6]) != tgt->scsi_id)
return 1;
--
2.13.6