From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarek Poplawski Subject: Re: [PATCH] tcp_output: Re: rare bad TCP checksum with 2.6.19? Date: Mon, 22 Jan 2007 07:52:14 +0100 Message-ID: <20070122065214.GA1634@ff.dom.local> References: <45AE2EDF.4060709@tls.msk.ru> <20070119110641.GA3135@ff.dom.local> <20070119211027.GA16626@gondor.apana.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Michael Tokarev , netdev@vger.kernel.org, Patrick McHardy , "David S\. Miller" Return-path: Received: from mx2.go2.pl ([193.17.41.42]:56575 "EHLO poczta.o2.pl" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751453AbXAVGty (ORCPT ); Mon, 22 Jan 2007 01:49:54 -0500 To: Herbert Xu Content-Disposition: inline In-Reply-To: <20070119211027.GA16626@gondor.apana.org.au> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Sat, Jan 20, 2007 at 08:10:27AM +1100, Herbert Xu wrote: > On Fri, Jan 19, 2007 at 12:06:41PM +0100, Jarek Poplawski wrote: > > > > [PATCH][NET] tcp_output: rare bad TCP checksum with 2.6.19 > > > > The patch "Replace CHECKSUM_HW by CHECKSUM_PARTIAL/CHECKSUM_COMPLETE" > > changed to unconditional copying of ip_summed field from collapsed > > skb. This patch reverts this change. > > > > All substantial work including heavy testing and diagnosing by: > > Michael Tokarev > > > > Signed-off-by: Jarek Poplawski > > Acked-by: Herbert Xu > > Thanks for catching this! I'll take the credit for adding this bug :) > > Dave, we'll need this fix for 2.6.20 as well as 2.6.19. I was so impressed by the amount of work done by Michael that I magnified his merit and forgot to mention the role of Patrick and Herbert, particularly here: > Since you're certain that this is being seen on the wire, one > possibility is that we've got a bug somewhere that's zeroing > skb->ip_summed on a packet with a partial checksum. which exactly pointed the reason. So, I apologize to them and, if there is such possibility, I would like to ask David Miller to change the description like that: --- [PATCH][NET] tcp_output: rare bad TCP checksum with 2.6.19 The patch "Replace CHECKSUM_HW by CHECKSUM_PARTIAL/CHECKSUM_COMPLETE" changed to unconditional copying of ip_summed field from collapsed skb. This patch reverts this change. The majority of substantial work including heavy testing and diagnosing by: Michael Tokarev Possible reasons pointed by: Herbert Xu and Patrick McHardy. Signed-off-by: Jarek Poplawski Acked-by: Herbert Xu --- Regards, Jarek P.