[PATCH 2/7] scsi: hisi_sas: Move evaluation of hisi_hba in hisi_sas_task_prep()

From: John Garry
Date: Mon Sep 24 2018 - 11:10:35 EST


From: Luo Jiaxing <luojiaxing@xxxxxxxxxx>

In evaluating hisi_hba, the sas_port may be NULL, so for safety relocate
the the check to value possible NULL deference.

Signed-off-by: Luo Jiaxing <luojiaxing@xxxxxxxxxx>
Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
---
drivers/scsi/hisi_sas/hisi_sas_main.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c
index ba6fb535..3b95a7a 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -287,13 +287,13 @@ static int hisi_sas_task_prep(struct sas_task *task,
int *pass)
{
struct domain_device *device = task->dev;
- struct hisi_hba *hisi_hba = dev_to_hisi_hba(device);
+ struct hisi_hba *hisi_hba;
struct hisi_sas_device *sas_dev = device->lldd_dev;
struct hisi_sas_port *port;
struct hisi_sas_slot *slot;
struct hisi_sas_cmd_hdr *cmd_hdr_base;
struct asd_sas_port *sas_port = device->port;
- struct device *dev = hisi_hba->dev;
+ struct device *dev;
int dlvry_queue_slot, dlvry_queue, rc, slot_idx;
int n_elem = 0, n_elem_req = 0, n_elem_resp = 0;
struct hisi_sas_dq *dq;
@@ -314,6 +314,9 @@ static int hisi_sas_task_prep(struct sas_task *task,
return -ECOMM;
}

+ hisi_hba = dev_to_hisi_hba(device);
+ dev = hisi_hba->dev;
+
if (DEV_IS_GONE(sas_dev)) {
if (sas_dev)
dev_info(dev, "task prep: device %d not ready\n",
--
1.9.1