Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758824AbYGPHae (ORCPT ); Wed, 16 Jul 2008 03:30:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754202AbYGPHaW (ORCPT ); Wed, 16 Jul 2008 03:30:22 -0400 Received: from smtp-out5.blueyonder.co.uk ([195.188.213.8]:52035 "EHLO smtp-out5.blueyonder.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751618AbYGPHaV convert rfc822-to-8bit (ORCPT ); Wed, 16 Jul 2008 03:30:21 -0400 Message-ID: <487DA388.3030104@jeffray.co.uk> Date: Wed, 16 Jul 2008 08:30:16 +0100 From: Ian Jeffray User-Agent: Thunderbird 2.0.0.14 (Windows/20080421) MIME-Version: 1.0 To: Eric Dumazet CC: linux-kernel@vger.kernel.org, Linux Netdev List Subject: Re: sendfile() broken with 2.6.26 + Apache 2 ? References: <487CD7A7.2080800@jeffray.co.uk> <487D893A.5080207@cosmosbay.com> In-Reply-To: <487D893A.5080207@cosmosbay.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1915 Lines: 61 Hi Eric, Thanks for directing me to a better list. Further responses below: Eric Dumazet wrote: > CC to netdev where this report might find better answers > > Ian Jeffray a ?crit : >> All, >> >> I moved from kernel 2.6.25.4 to 2.6.26 yesterday and observed that >> large files sent via Apache2 are partially corrupt. >> >> This appears to be linked to sendfile() -- disabling the use of >> sendfile in the apache config (EnableSendfile Off) allows it to >> function as normal. >> >> My system is a simple Core2Duo running Debian lenny/sid; nothing >> special, and I have never observed problems like this before. >> >> The problem feels certainly related to sendfile() since the data >> reads correctly from disc in other programs, and via CIFS etc. >> >> The corruption happens part-way in to the file... I've no exact >> figure but it would seem like maybe 32KB -- I'm seeing broken >> PNGs served from Apache, where the top few dozen lines decode >> correctly, and the rest is garbage. >> >> I've made basically no configuration changes between 2.6.25.4 and >> 2.6.26 and have explicitly tried both enabling and disabling the >> new PAT support to no effect. >> >> This is completely repeatable and reproducible. >> >> Is anyone else seeing this broken behaviour? >> > > > What kind of network adapter are you using ? (lspci | grep -i ether) 02:00.0 Ethernet controller: Attansic Technology Corp. L1 Gigabit Ethernet Adapter (rev b0) > If you disable TCP segmentation offload on this NIC (ethtool -K eth0 tso > off) , is this problem still present ? Wow. That 'solves' the problem! Great. Does this therefore point to an attansic driver issue? Ian. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/