Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (38 commits)
  ip_gre: include route header_len in max_headroom calculation
  if_tunnel.h: add missing ams/byteorder.h include
  ipv4: Don't drop redirected route cache entry unless PTMU actually expired
  net: suppress lockdep-RCU false positive in FIB trie.
  Bluetooth: Fix kernel crash on L2CAP stress tests
  Bluetooth: Convert debug files to actually use debugfs instead of sysfs
  Bluetooth: Fix potential bad memory access with sysfs files
  netfilter: ctnetlink: fix reliable event delivery if message building fails
  netlink: fix NETLINK_RECV_NO_ENOBUFS in netlink_set_err()
  NET_DMA: free skbs periodically
  netlink: fix unaligned access in nla_get_be64()
  tcp: Fix tcp_mark_head_lost() with packets == 0
  net: ipmr/ip6mr: fix potential out-of-bounds vif_table access
  KS8695: update ksp->next_rx_desc_read at the end of rx loop
  igb: Add support for 82576 ET2 Quad Port Server Adapter
  ixgbevf: Message formatting cleanups
  ixgbevf: Shorten up delay timer for watchdog task
  ixgbevf: Fix VF Stats accounting after reset
  ixgbe: Set IXGBE_RSC_CB(skb)->DMA field to zero after unmapping the address
  ixgbe: fix for real_num_tx_queues update issue
  ...

1 files changed, 15 insertions, 3 deletions

diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c
index d222d7e25273..73f9a31cf94d 100644
--- a/drivers/net/usb/smsc95xx.c
+++ b/drivers/net/usb/smsc95xx.c
@@ -1189,9 +1189,21 @@ static struct sk_buff *smsc95xx_tx_fixup(struct usbnet *dev,
         }
 
         if (csum) {
-                u32 csum_preamble = smsc95xx_calc_csum_preamble(skb);
-                skb_push(skb, 4);
-                memcpy(skb->data, &csum_preamble, 4);
+                if (skb->len <= 45) {
+                        /* workaround - hardware tx checksum does not work
+                         * properly with extremely small packets */
+                        long csstart = skb->csum_start - skb_headroom(skb);
+                        __wsum calc = csum_partial(skb->data + csstart,
+                                skb->len - csstart, 0);
+                        *((__sum16 *)(skb->data + csstart
+                                + skb->csum_offset)) = csum_fold(calc);
+
+                        csum = false;
+                } else {
+                        u32 csum_preamble = smsc95xx_calc_csum_preamble(skb);
+                        skb_push(skb, 4);
+                        memcpy(skb->data, &csum_preamble, 4);
+                }
         }
 
         skb_push(skb, 4);