From: Johannes Thumshirn <jthumshirn@suse.de>
Date: Fri, 23 Mar 2018 14:37:05 +0100
Subject: [PATCH] scsi: scsi_dh: Don't look for NULL devices handlers by name
Git-commit: 2ee5671e3ae35e53bb5a53a89ac8f033e4b1721f
Patch-mainline: v4.17-rc1
References: bsc#1118139
Currently scsi_dh_lookup() doesn't check for NULL as a device name. This
combined with nvme over dm-mpath results in the following messages
emitted by device-mapper:
device-mapper: multipath: Could not failover device 259:67: Handler scsi_dh_(null) error 14.
Let scsi_dh_lookup() fail fast on NULL names.
[mkp: typo fix]
Cc: <stable@vger.kernel.org> # v4.16
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Hannes Reinecke <hare@suse.com>
---
drivers/scsi/scsi_dh.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/scsi/scsi_dh.c b/drivers/scsi/scsi_dh.c
index b88b5dbbc444..188f30572aa1 100644
--- a/drivers/scsi/scsi_dh.c
+++ b/drivers/scsi/scsi_dh.c
@@ -112,6 +112,9 @@ static struct scsi_device_handler *scsi_dh_lookup(const char *name)
{
struct scsi_device_handler *dh;
+ if (!name || strlen(name) == 0)
+ return NULL;
+
dh = __scsi_dh_lookup(name);
if (!dh) {
request_module("scsi_dh_%s", name);
--
2.12.3