Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751756AbXBCWcn (ORCPT ); Sat, 3 Feb 2007 17:32:43 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751771AbXBCWcm (ORCPT ); Sat, 3 Feb 2007 17:32:42 -0500 Received: from 1wt.eu ([62.212.114.60]:2238 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751741AbXBCWcl (ORCPT ); Sat, 3 Feb 2007 17:32:41 -0500 Date: Sat, 3 Feb 2007 23:32:31 +0100 From: Willy Tarreau To: Stephen Hemminger Cc: Linus Torvalds , Jeff Garzik , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] sky2: flow control off Message-ID: <20070203223231.GG24090@1wt.eu> References: <20070202153425.2d979fd4@freekitty> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070202153425.2d979fd4@freekitty> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1798 Lines: 36 Hi Stephen, On Fri, Feb 02, 2007 at 03:34:25PM -0800, Stephen Hemminger wrote: > Turn flow control off for sky2. When flow control is on, the transmitter > may get randomly stuck. Perhaps there is hardware problem, but until > Marvell provides errata information for workaround, it should default to off. Are you aware of any way to reproduce or at least to increases chances of occurrences of this problem ? It looks much like a problem I've been experiencing with Marvell's driver with a 88E8053 chip on 2.4. Doing "ethtool -r" proved useful to reset the transceiver in production. When trying to reproduce the problem, I noticed corrupted and duplicated frames in tcpdump captures when packets between 147 and 496 bytes were received then re-routed via the same NIC towards a 100 Mbps machine on the same switch, a Gig Dlink doing flow control. Yes, I know, there are a lot of variables ! But changing the target machine, or the packet sizes was enough to stop the corruption. I could not get the transmitter stuck as I sometimes have in production, but I think that both problems are related. The fact that a comparable problem is encountered with your driver really makes me think about a hardware bug :-/ BTW, switching to your driver (sky2-1.5), I could not reproduce the corruption problem anymore, but I've not yet put it in production to check if it fixes the transceiver problem. Anyway, it might be interesting that users who encounter this problem try an old version of the driver just in case they detect a difference. regards, Willy - 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/