From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Hutchings Subject: Re: TSO/GRO/LRO/somethingO breaks LVS on 2.6.36 Date: Fri, 03 Dec 2010 13:27:19 +0000 Message-ID: <1291382839.8025.40.camel@localhost> References: <20101203103447.GA29714@hostway.ca> <1291375743.2897.141.camel@edumazet-laptop> <20101203123617.GA6993@verge.net.au> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: Eric Dumazet , Simon Kirby , netdev@vger.kernel.org To: Simon Horman Return-path: Received: from mail.solarflare.com ([216.237.3.220]:50875 "EHLO exchange.solarflare.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751669Ab0LCN10 (ORCPT ); Fri, 3 Dec 2010 08:27:26 -0500 In-Reply-To: <20101203123617.GA6993@verge.net.au> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, 2010-12-03 at 21:36 +0900, Simon Horman wrote: > On Fri, Dec 03, 2010 at 12:29:03PM +0100, Eric Dumazet wrote: [...] > > I believe Simon Horman has some patches for GRO and LVS. > > > > Please send the results of "ethtool -k eth0" on all your nics / vlans ? > > > > For TSO, I am not sure why and where it could matter... > > There is a patch to teach LVS how to cope with GRO in nf-next-2.6 > and I expect it to be included in 2.6.38. The patch is "ipvs: allow > transmit of GRO aggregated skbs" and perhaps it should be considered > for 2.6.37 and stable. In general the work around is to disable GRO. > > The patch does not resolve the incompatibility of LVS with LRO. > The work around there is to disable LRO. I'm not entirely sure > how to teach LVS to disable LRO automatically, or if its desirable. [...] I think it is desirable, and we already do it for bridging and forwarding - we call dev_disable_lro() whenever a device is added to a bridge or has forwarding enabled. For IPVS it looks like you would have to resolve the server IP address to a device first. Though if the administrator assigns the server address to a different interface later then the failure mode will be very hard to understand. Ben. -- Ben Hutchings, Senior Software Engineer, Solarflare Communications Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked.