From: Huazhong Tan <tanhuazhong@huawei.com>
Date: Tue, 30 Oct 2018 21:50:46 +0800
Subject: net: hns3: bugfix for the initialization of command queue's spin lock
Patch-mainline: v4.20-rc1
Git-commit: b2f74dbaf12bf59ff35d451005b3cdee78232ff0
References: bsc#1104353 FATE#326415

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 <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_cmd.c |   14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_cmd.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_cmd.c
@@ -304,6 +304,10 @@ int hclge_cmd_queue_init(struct hclge_de
 {
 	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;
@@ -337,18 +341,20 @@ int hclge_cmd_init(struct hclge_dev *hde
 	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);
 	clear_bit(HCLGE_STATE_CMD_DISABLE, &hdev->state);
 
+	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,