From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [PATCH][RFC] network splice receive Date: Wed, 6 Jun 2007 09:14:08 +0200 Message-ID: <20070606071407.GD31415@kernel.dk> References: <20070605080542.GA9909@kernel.dk> <20070605114545.GC9909@kernel.dk> <20070605122031.GE9909@kernel.dk> <1181046894.5896.5.camel@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org To: jamal Return-path: Received: from brick.kernel.dk ([80.160.20.94]:14811 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750886AbXFFHQH (ORCPT ); Wed, 6 Jun 2007 03:16:07 -0400 Content-Disposition: inline In-Reply-To: <1181046894.5896.5.camel@localhost> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Tue, Jun 05 2007, jamal wrote: > On Tue, 2007-05-06 at 14:20 +0200, Jens Axboe wrote: > > > > > > > 0000 1800 4ff3 937f e000 6381 7275 0008 > > > > > > Perhaps that hex pattern rings a bell with someone intimate with the > > > networking. The remaining wrong bytes don't seem to have anything in > > > common. > > > > Ok, the source mac address is 00:18:F3:4F:7F:93 and the destination is > > 00:E0:81:63:75:72 which are the middle 12 bytes of the 16. > > > > It appears you may have endianness issues and perhaps a 16 bit > mis-offset. the 0008 at the end looks like a swapped 0x800 which > is the ethernet type for IPV4. Yeah, it looks like the first part of the ethernet frame. I'm using an e1000 on the receive side and a sky2 on the sender. > > Hope that helps someone clue me in as to which network part is reusing > > the data. Do I need to 'pin' the sk_buff until the pipe data has been > > consumed? > > I would worry about the driver level first - likely thats where your > corruption is. I'd just be a heck-of-a-lot more inclined to suspect my code! Hence I thought that data reuse for perhaps another packet would be the likely explanation, especially since it looked like valid network driver data ending up where it should not. -- Jens Axboe