Subject: [PATCH AUTOSEL 4.18 09/39] net: hns3: bugfix for the initialization of command queue's spin lock

From: Sasha Levin <[email-masked]>
Date: Tue, 13 Nov 2018 00:50:23 -0500

From: Huazhong Tan <[email-masked]>

[ Upstream commit b2f74dbaf12bf59ff35d451005b3cdee78232ff0 ]

The spin lock of the command queue only need to be initialized once
when the driver initializes the command queue. It is not necessary to
initialize the spin lock when resetting. At the same time, the
modification of the queue member should be performed after acquiring
the lock.

Fixes: 3efb960f056d ("net: hns3: Refactor the initialization of command queue")
Signed-off-by: Huazhong Tan <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
Signed-off-by: Sasha Levin <[email-masked]>
---
 .../net/ethernet/hisilicon/hns3/hns3pf/hclge_cmd.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_cmd.c b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_cmd.c
index c36d64710fa6..fda9d64bc6e9 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_cmd.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_cmd.c
@@ -326,6 +326,10 @@ int hclge_cmd_queue_init(struct hclge_dev *hdev)
 {
 	int ret;
 
+	/* Setup the lock for command queue */
+	spin_lock_init(&hdev->hw.cmq.csq.lock);
+	spin_lock_init(&hdev->hw.cmq.crq.lock);
+
 	/* Setup the queue entries for use cmd queue */
 	hdev->hw.cmq.csq.desc_num = HCLGE_NIC_CMQ_DESC_NUM;
 	hdev->hw.cmq.crq.desc_num = HCLGE_NIC_CMQ_DESC_NUM;
@@ -359,17 +363,19 @@ int hclge_cmd_init(struct hclge_dev *hdev)
 	u32 version;
 	int ret;
 
+	spin_lock_bh(&hdev->hw.cmq.csq.lock);
+	spin_lock_bh(&hdev->hw.cmq.crq.lock);
+
 	hdev->hw.cmq.csq.next_to_clean = 0;
 	hdev->hw.cmq.csq.next_to_use = 0;
 	hdev->hw.cmq.crq.next_to_clean = 0;
 	hdev->hw.cmq.crq.next_to_use = 0;
 
-	/* Setup the lock for command queue */
-	spin_lock_init(&hdev->hw.cmq.csq.lock);
-	spin_lock_init(&hdev->hw.cmq.crq.lock);
-
 	hclge_cmd_init_regs(&hdev->hw);
 
+	spin_unlock_bh(&hdev->hw.cmq.crq.lock);
+	spin_unlock_bh(&hdev->hw.cmq.csq.lock);
+
 	ret = hclge_cmd_query_firmware_version(&hdev->hw, &version);
 	if (ret) {
 		dev_err(&hdev->pdev->dev,
-- 
2.17.1