From: Huazhong Tan <tanhuazhong@huawei.com>
Date: Sat, 2 Feb 2019 22:39:32 +0800
Subject: net: hns3: fix a wrong checking in the hclge_tx_buffer_calc()
Patch-mainline: v5.1-rc1
Git-commit: b6b4f987c5c4fe488f3f68460b9addc08482b164
References: bsc#1126390

Only the TC is enabled, we need to check whether the buffer is enough,
otherwise it may lead to a wrong -ENOMEM case.

Fixes: 9ffe79a9c2ee ("net: hns3: Support for dynamically assigning tx buffer to TC")
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: Peng Li <lipeng321@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_main.c |    9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
@@ -1506,13 +1506,14 @@ static int hclge_tx_buffer_calc(struct h
 	for (i = 0; i < HCLGE_MAX_TC_NUM; i++) {
 		struct hclge_priv_buf *priv = &buf_alloc->priv_buf[i];
 
-		if (total_size < hdev->tx_buf_size)
-			return -ENOMEM;
+		if (hdev->hw_tc_map & BIT(i)) {
+			if (total_size < hdev->tx_buf_size)
+				return -ENOMEM;
 
-		if (hdev->hw_tc_map & BIT(i))
 			priv->tx_buf_size = hdev->tx_buf_size;
-		else
+		} else {
 			priv->tx_buf_size = 0;
+		}
 
 		total_size -= priv->tx_buf_size;
 	}