From: Xiang Chen <chenxiang66@hisilicon.com>
Date: Thu, 18 Jan 2018 00:46:54 +0800
Subject: scsi: hisi_sas: fix a bug in hisi_sas_dev_gone()
Git-commit: 0d762b3af2a5b5095fec18aa4d61f408638aa9ca
Patch-mainline: v4.16-rc1
References: FATE#326253

When device gone, NULL pointer can be accessed in free_device callback
if during SAS controller reset as we clear structure sas_dev prior.

Actually we can only set dev_type as SAS_PHY_UNUSED and not clear
structure sas_dev as all the members of structure sas_dev will be
re-initialized after device found.

Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
---
 drivers/scsi/hisi_sas/hisi_sas_main.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c
index 791462d7fbfc..2d4dbed03ee3 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -796,7 +796,6 @@ static void hisi_sas_dev_gone(struct domain_device *device)
 
 		hisi_hba->hw->clear_itct(hisi_hba, sas_dev);
 		device->lldd_dev = NULL;
-		memset(sas_dev, 0, sizeof(*sas_dev));
 	}
 
 	if (hisi_hba->hw->free_device)