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

BugLink: https://bugs.launchpad.net/bugs/1862429
[ Upstream commit 36c67349a1a1c88b9cf11d7ca7762ababdb38867 ]

The hardware can not handle short frames below or equal to 32
bytes according to the hardware user manual, and it will trigger
a RAS error when the frame's length is below 33 bytes.

This patch pads the SKB when skb->len is below 33 bytes before
sending it to hardware.

Fixes: 76ad4f0ee747 ("net: hns3: Add support of HNS3 Ethernet Driver for hip08 SoC")
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
index 525f49a17555533e020fb01e626afb5bea8b674d..f6323d9dc78ad095c7abb769f4afe2538e350f52 100644 (file)
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
@@ -45,6 +45,8 @@ MODULE_PARM_DESC(debug, " Network interface message level setting");
 #define DEFAULT_MSG_LEVEL (NETIF_MSG_PROBE | NETIF_MSG_LINK | \
                           NETIF_MSG_IFDOWN | NETIF_MSG_IFUP)
 
+#define HNS3_MIN_TX_LEN                33U
+
 /* hns3_pci_tbl - PCI Device ID Table
  *
  * Last entry must be all 0s
@@ -1298,6 +1300,10 @@ netdev_tx_t hns3_nic_net_xmit(struct sk_buff *skb, struct net_device *netdev)
        int ret;
        int i;
 
+       /* Hardware can only handle short frames above 32 bytes */
+       if (skb_put_padto(skb, HNS3_MIN_TX_LEN))
+               return NETDEV_TX_OK;
+
        /* Prefetch the data used later */
        prefetch(skb->data);