From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Fitzhardinge Subject: Re: [PATCH] xen: netfront: Drop GSO SKBs which do not have csum_blank. Date: Fri, 21 Jan 2011 16:58:58 -0800 Message-ID: <4D3A2BD2.5030802@goop.org> References: <1294233811-28123-1-git-send-email-ian.campbell@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, xen-devel@lists.xensource.com To: Ian Campbell Return-path: Received: from claw.goop.org ([74.207.240.146]:41978 "EHLO claw.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750791Ab1AVA7C (ORCPT ); Fri, 21 Jan 2011 19:59:02 -0500 In-Reply-To: <1294233811-28123-1-git-send-email-ian.campbell@citrix.com> Sender: netdev-owner@vger.kernel.org List-ID: On 01/05/2011 05:23 AM, Ian Campbell wrote: > The Linux network stack expects all GSO SKBs to have ip_summed == > CHECKSUM_PARTIAL (which implies that the frame contains a partial > checksum) and the Xen network ring protocol similarly expects an SKB > which has GSO set to also have NETRX_csum_blank (which also implies a > partial checksum). Therefore drop such frames on receive otherwise > they will trigger the warning in skb_gso_segment. > > Signed-off-by: Ian Campbell > Cc: Jeremy Fitzhardinge > Cc: xen-devel@lists.xensource.com > Cc: netdev@vger.kernel.org > --- > drivers/net/xen-netfront.c | 5 +++++ > 1 files changed, 5 insertions(+), 0 deletions(-) > > diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c > index cdbeec9..8b8c480 100644 > --- a/drivers/net/xen-netfront.c > +++ b/drivers/net/xen-netfront.c > @@ -836,6 +836,11 @@ static int handle_incoming_queue(struct net_device *dev, > dev->stats.rx_errors++; > continue; > } > + } else if (skb_is_gso(skb)) { > + kfree_skb(skb); > + packets_dropped++; > + dev->stats.rx_errors++; > + continue; This looks redundant; why not something like: diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 47e6a71..c1b8f64 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -852,13 +852,12 @@ static int handle_incoming_queue(struct net_device *dev, /* Ethernet work: Delayed to here as it peeks the header. */ skb->protocol = eth_type_trans(skb, dev); - if (skb->ip_summed == CHECKSUM_PARTIAL) { - if (skb_checksum_setup(skb)) { - kfree_skb(skb); - packets_dropped++; - dev->stats.rx_errors++; - continue; - } + if (skb->ip_summed != CHECKSUM_PARTIAL || + skb_checksum_setup(skb)) { + kfree_skb(skb); + packets_dropped++; + dev->stats.rx_errors++; + continue; } dev->stats.rx_packets++; Thanks, J