This patch fixes the problem where tcpdump shows duplicate packets while tracing outbound packets on drivers which support lockless transmit. The patch changes the current behaviour to tracing the packets only on a successful transmit.
Signed-off-by: Ranjit Manomohan <[EMAIL PROTECTED]> --- linux-2.6/net/sched/sch_generic.c 2006-05-10 12:34:52.000000000 -0700 +++ linux/net/sched/sch_generic.c 2006-05-10 12:39:38.000000000 -0700 @@ -136,8 +136,12 @@ if (!netif_queue_stopped(dev)) { int ret; + struct sk_buff *skbc = NULL; + /* Clone the skb so that we hold a reference + * to its data and we can trace it after a + * successful transmit. */ if (netdev_nit) - dev_queue_xmit_nit(skb, dev); + skbc = skb_clone(skb, GFP_ATOMIC); ret = dev->hard_start_xmit(skb, dev); if (ret == NETDEV_TX_OK) { @@ -145,6 +149,15 @@ dev->xmit_lock_owner = -1; spin_unlock(&dev->xmit_lock); } + if(skbc) { + /* transmit succeeded, + * trace the clone. */ + dev_queue_xmit_nit(skbc,dev); + kfree_skb(skbc); + } + /* Free clone if it exists */ + if(skbc) + kfree_skb(skbc); spin_lock(&dev->queue_lock); return -1; } - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html