From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH 02/11] sky2: fix DMA sync_single length error Date: Wed, 20 Jan 2010 16:15:34 -0800 (PST) Message-ID: <20100120.161534.173867444.davem@davemloft.net> References: <20100120.154126.152942350.davem@davemloft.net> <20100120235920.GF3072@del.dom.local> <20100120160407.3a365a92@nehalam> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: jarkao2@gmail.com, netdev@vger.kernel.org To: shemminger@vyatta.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:45739 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754736Ab0AUAPY (ORCPT ); Wed, 20 Jan 2010 19:15:24 -0500 In-Reply-To: <20100120160407.3a365a92@nehalam> Sender: netdev-owner@vger.kernel.org List-ID: From: Stephen Hemminger Date: Wed, 20 Jan 2010 16:04:07 -0800 > The usage of jumbo frames on the Marvell Yukon-2 chip version that > Michael has is suspect. In order to do Jumbo frames, the driver has > turns off the store-forward buffer; this reduces the window for transmit > underrun, and triggers a problem. I suspect the unwind logic for > transmit underrun is broken and may not be fixable without more hardware > information. Turning off jumbo frame support for that chip type > is probably the safest solution. So let's do that. Meanwhile I think the DMA debugging patch you posted earlier today need a little work, will reply there.