Subject: Re: [patch 4/10] s390: network driver.

From: Peter Buckingham <[email-masked]>
Date: Mon, 17 Jan 2005 14:13:40 -0800

Hi,

Tommy Christensen wrote:
> A proper solution would take care of both these issues: "stale packets"
> and "socket blocking". They are pretty much related.
> 
> Using a socket for each interface *ought* not be needed.
> Carrier detection sounds like a good thing in its own right.

I came across this same problem with multicast/unicast with an e1000. 
For a quick hack we just check to see whether the carrier is ok, if it's 
not we just drop the packet. this might do some nasty things with tcp 
and it may be better to check to see wither the socket buffer is full, 
but this works for me here... (this is against a 2.6.9ish kernel)

peter

Index: net/core/dev.c
===================================================================
--- net/core/dev.c
+++ net/core/dev.c
@@ -1379,6 +1379,11 @@
  #ifdef CONFIG_NET_CLS_ACT
  	skb->tc_verd = SET_TC_AT(skb->tc_verd,AT_EGRESS);
  #endif
+	if (!netif_carrier_ok(dev)) {
+		rc = NET_XMIT_DROP;
+		goto out_kfree_skb;
+	}
+
  	if (q->enqueue) {
  		/* Grab device queue */
  		spin_lock(&dev->queue_lock);