net: hns3: pad the short tunnel frame before sending to hardware

The hardware cannot handle short tunnel frames below 65 bytes,
and will cause vlan tag missing problem. So pads packet size to
65 bytes for tunnel frames to fix this bug.

Fixes: 3db084d28dc0("net: hns3: Fix for vxlan tx checksum bug")
Signed-off-by: Yufeng Mo <moyufeng@huawei.com>
Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
index 293243b..adc54a7 100644 (file)
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
@@ -76,6 +76,7 @@ module_param(page_pool_enabled, bool, 0400);
 #define HNS3_OUTER_VLAN_TAG    2
 
 #define HNS3_MIN_TX_LEN                33U
+#define HNS3_MIN_TUN_PKT_LEN   65U
 
 /* hns3_pci_tbl - PCI Device ID Table
  *
@@ -1427,8 +1428,11 @@ static int hns3_set_l2l3l4(struct sk_buff *skb, u8 ol4_proto,
                               l4.tcp->doff);
                break;
        case IPPROTO_UDP:
-               if (hns3_tunnel_csum_bug(skb))
-                       return skb_checksum_help(skb);
+               if (hns3_tunnel_csum_bug(skb)) {
+                       int ret = skb_put_padto(skb, HNS3_MIN_TUN_PKT_LEN);
+
+                       return ret ? ret : skb_checksum_help(skb);
+               }
 
                hns3_set_field(*type_cs_vlan_tso, HNS3_TXD_L4CS_B, 1);
                hns3_set_field(*type_cs_vlan_tso, HNS3_TXD_L4T_S,