The smsc95xx_tx_fixup is doing multiple calls to skb_push() to
put an 8-byte command header onto the packet. It would be easier
to do one skb_push() and then copy the data in once the push is
done.

Signed-off-by: Ben Dooks <ben.do...@codethink.co.uk>
---
 drivers/net/usb/smsc95xx.c | 25 +++++++++++++------------
 1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c
index cb19aea139d3..813ab93ee2c3 100644
--- a/drivers/net/usb/smsc95xx.c
+++ b/drivers/net/usb/smsc95xx.c
@@ -2006,6 +2006,7 @@ static struct sk_buff *smsc95xx_tx_fixup(struct usbnet 
*dev,
        bool csum = skb->ip_summed == CHECKSUM_PARTIAL;
        int overhead = csum ? SMSC95XX_TX_OVERHEAD_CSUM : SMSC95XX_TX_OVERHEAD;
        u32 tx_cmd_a, tx_cmd_b;
+       void *ptr;
 
        /* We do not advertise SG, so skbs should be already linearized */
        BUG_ON(skb_shinfo(skb)->nr_frags);
@@ -2019,6 +2020,9 @@ static struct sk_buff *smsc95xx_tx_fixup(struct usbnet 
*dev,
                return NULL;
        }
 
+       tx_cmd_b = (u32)skb->len;
+       tx_cmd_a = tx_cmd_b | TX_CMD_A_FIRST_SEG_ | TX_CMD_A_LAST_SEG_;
+
        if (csum) {
                if (skb->len <= 45) {
                        /* workaround - hardware tx checksum does not work
@@ -2035,21 +2039,18 @@ static struct sk_buff *smsc95xx_tx_fixup(struct usbnet 
*dev,
                        skb_push(skb, 4);
                        cpu_to_le32s(&csum_preamble);
                        memcpy(skb->data, &csum_preamble, 4);
+
+                       tx_cmd_a += 4;
+                       tx_cmd_b += 4;
+                       tx_cmd_b |= TX_CMD_B_CSUM_ENABLE;
                }
        }
 
-       skb_push(skb, 4);
-       tx_cmd_b = (u32)(skb->len - 4);
-       if (csum)
-               tx_cmd_b |= TX_CMD_B_CSUM_ENABLE;
-       cpu_to_le32s(&tx_cmd_b);
-       memcpy(skb->data, &tx_cmd_b, 4);
-
-       skb_push(skb, 4);
-       tx_cmd_a = (u32)(skb->len - 8) | TX_CMD_A_FIRST_SEG_ |
-               TX_CMD_A_LAST_SEG_;
-       cpu_to_le32s(&tx_cmd_a);
-       memcpy(skb->data, &tx_cmd_a, 4);
+       ptr = skb_push(skb, 8);
+       tx_cmd_a = cpu_to_le32(tx_cmd_a);
+       tx_cmd_b = cpu_to_le32(tx_cmd_b);
+       memcpy(ptr, &tx_cmd_a, 4);
+       memcpy(ptr+4, &tx_cmd_b, 4);
 
        return skb;
 }
-- 
2.19.0

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