From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Hutchings Subject: Re: Misuse of LRO, how widespread Date: Mon, 06 Dec 2010 23:22:35 +0000 Message-ID: <1291677755.5405.29.camel@bwh-desktop> References: <20101206121829.5b8c852e@nehalam> <4CFD527E.7000706@chelsio.com> <20101206142715.0d296b25@nehalam> <4CFD6C2B.9020201@chelsio.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: Stephen Hemminger , David Miller , Olof Johansson , Divy Le Ray , netdev@vger.kernel.org To: Dimitris Michailidis Return-path: Received: from mail.solarflare.com ([216.237.3.220]:31340 "EHLO exchange.solarflare.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754216Ab0LFXWl (ORCPT ); Mon, 6 Dec 2010 18:22:41 -0500 In-Reply-To: <4CFD6C2B.9020201@chelsio.com> Sender: netdev-owner@vger.kernel.org List-ID: On Mon, 2010-12-06 at 15:05 -0800, Dimitris Michailidis wrote: > Stephen Hemminger wrote: > > On Mon, 06 Dec 2010 13:15:42 -0800 > > Dimitris Michailidis wrote: > > > >> Stephen Hemminger wrote: > >>> I inspected all drivers in net-next to see which drivers are using > >>> LRO and which ones are broken. Most concerning is that Chelsio > >>> and Solarflare drivers ignore ETH_FLAG_LRO. > >>> > >>> The ones that are using LRO but allow disabling it: > >>> qlcnic, netxen, mv643, s2io, myi10ge, bnx2x, ixgbe, vmxnet3 > >>> > >>> One driver seems confused about LRO vs GRO: > >>> mlx4 - comments about LRO and depends on LRO but driver is using GRO > >>> > >>> Drivers with not using ethtool interface to disable LRO: > >>> pasemi_mac, sfc, ehea, cxgb3, cxgb4 > >> cxgb4 uses GRO, not LRO. > > > > Ok. but cxgb3 still uses LRO (or it least calls it lro). > > > > cxgb3 was the driver Herbert implemented GRO on I think, and he converted it > to GRO. It possibly has leftover LRO references as it was using LRO before. There's a fair amount of code setting LRO flags in various structures, so either the driver still enables LRO in hardware/firmware or this is dead code. 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.