From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Daniel J Blueman" Subject: Re: sky2 hw csum failure [was Re: sky2 large MTU problems] Date: Tue, 30 May 2006 10:10:11 +0100 Message-ID: <6278d2220605300210u101d65a9u93354aecbcde99a@mail.gmail.com> References: <6278d2220605240228v576dd66atdad4855b308e64bf@mail.gmail.com> <20060524103820.2e213a0b@localhost.localdomain> <44758881.1020106@trash.net> <6278d2220605250355y316f974cl216f22d198475666@mail.gmail.com> <447591DB.2020901@trash.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: "Stephen Hemminger" , netdev@vger.kernel.org, "Netfilter Developer" Return-path: Received: from wr-out-0506.google.com ([64.233.184.227]:49567 "EHLO wr-out-0506.google.com") by vger.kernel.org with ESMTP id S932194AbWE3JKN (ORCPT ); Tue, 30 May 2006 05:10:13 -0400 Received: by wr-out-0506.google.com with SMTP id i7so1057185wra for ; Tue, 30 May 2006 02:10:12 -0700 (PDT) To: "Patrick McHardy" In-Reply-To: <447591DB.2020901@trash.net> Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 25/05/06, Patrick McHardy wrote: > Daniel J Blueman wrote: > > On 25/05/06, Patrick McHardy wrote: > > > >> Daniel, is there an easy way to reproduce the checksum failure? > > > > In short, no. This was seen when packets may have been truncated by > > large MTU (eg 9000) problems in the sky2 driver transmit path. > > > > There is a small chance that this could relate to transmitting with an > > MTU of 9000 (possibly with receiving with an MTU of 1500 too) > > Unfortunately I can't test this myself because my other NICs don't > support MTUs > 1500. > > > On that interface, the only rules that were being exercised were: > > > > iptables -t filter -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT > > iptables -t filter -A INPUT -p tcp -m tcp --dport 445 --syn -j ACCEPT # SMB > > iptables -t filter -A INPUT -j DROP > > That shouldn't cause any packet modifications. Can you trigger the > checksum failures without netfilter? When testing, I always run into the "kernel: sky2 lan0: rx error, status 0x977d977d length 0" problem before anything else. I need to eliminate the sky2 driver from the equation before I'm able to prove if there is a problem elsewhere or not. I did have some e1000 NICs, but not any longer, so it'll have to wait until I can find a stable scenario for my sky2 NIC... -- Daniel J Blueman