From 67fd1a731ff1a990d4da7689909317756e50cb4d Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Mon, 19 Jan 2009 16:26:44 -0800 Subject: [PATCH] net: Add debug info to track down GSO checksum bug I'm trying to track down why people're hitting the checksum warning in skb_gso_segment. As the problem seems to be hitting lots of people and I can't reproduce it or locate the bug, here is a patch to print out more details which hopefully should help us to track this down. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/core/dev.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/net/core/dev.c b/net/core/dev.c index 8d675975d85..6e44c327710 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1534,7 +1534,19 @@ struct sk_buff *skb_gso_segment(struct sk_buff *skb, int features) skb->mac_len = skb->network_header - skb->mac_header; __skb_pull(skb, skb->mac_len); - if (WARN_ON(skb->ip_summed != CHECKSUM_PARTIAL)) { + if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { + struct net_device *dev = skb->dev; + struct ethtool_drvinfo info = {}; + + if (dev && dev->ethtool_ops && dev->ethtool_ops->get_drvinfo) + dev->ethtool_ops->get_drvinfo(dev, &info); + + WARN(1, "%s: caps=(0x%lx, 0x%lx) len=%d data_len=%d " + "ip_summed=%d", + info.driver, dev ? dev->features : 0L, + skb->sk ? skb->sk->sk_route_caps : 0L, + skb->len, skb->data_len, skb->ip_summed); + if (skb_header_cloned(skb) && (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC))) return ERR_PTR(err); -- 2.41.1