According to RFC 2460, IPv6 UDP calculated checksum yields a result

of zero must be changed to 0xffff, however this feature is not
supported by smsc95xx family hence enable csum offload only for
IPv4 TCP/UDP packets.

Signed-off-by: Nisar Sayed <Nisar.Sayed@microchip.com>
Reported-by: popcorn mix <popcornmix@gmail.com>

diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c
index f6661e388f6e801c1b88e48a3b71407bd70cf56e..b84e98508b5d97165b68dfc30240950e78bb14c3 100644 (file)
--- a/drivers/net/usb/smsc95xx.c
+++ b/drivers/net/usb/smsc95xx.c
@@ -694,7 +694,7 @@ static int smsc95xx_set_features(struct net_device *netdev,
        if (ret < 0)
                return ret;
 
-       if (features & NETIF_F_HW_CSUM)
+       if (features & NETIF_F_IP_CSUM)
                read_buf |= Tx_COE_EN_;
        else
                read_buf &= ~Tx_COE_EN_;
@@ -1342,12 +1342,16 @@ static int smsc95xx_bind(struct usbnet *dev, struct usb_interface *intf)
 
        spin_lock_init(&pdata->mac_cr_lock);
 
+       /* RFC 2460, IPv6 UDP calculated checksum yields a result of zero must be
+        * changed to 0xffff, this feature is not supported by smsc95xx family,
+        * hence enable csum offload only for IPv4 TCP/UDP packets.
+        */
        if (DEFAULT_TX_CSUM_ENABLE)
-               dev->net->features |= NETIF_F_HW_CSUM;
+               dev->net->features |= NETIF_F_IP_CSUM;
        if (DEFAULT_RX_CSUM_ENABLE)
                dev->net->features |= NETIF_F_RXCSUM;
 
-       dev->net->hw_features = NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
+       dev->net->hw_features = NETIF_F_IP_CSUM | NETIF_F_RXCSUM;
 
        smsc95xx_init_mac_address(dev);