From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Larson Subject: MV643xx Ethernet Driver Issue on a Motorola PrPMC-275 board. Date: Tue, 29 Jul 2008 10:49:09 -0700 Message-ID: <488F5815.9020402@mvista.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit To: netdev@vger.kernel.org Return-path: Received: from gateway-1237.mvista.com ([63.81.120.158]:33343 "EHLO gateway-1237.mvista.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751811AbYG2Rsl (ORCPT ); Tue, 29 Jul 2008 13:48:41 -0400 Received: from [10.50.1.118] (unknown [10.50.1.118]) by hermes.mvista.com (Postfix) with ESMTP id 21905182B0 for ; Tue, 29 Jul 2008 10:48:40 -0700 (PDT) Sender: netdev-owner@vger.kernel.org List-ID: Greetings, I was wondering if anyone had any advice on an issue a customer of ours is running into. When they run a series of bandwidth tests, slowly increasing the bandwidth & # of tcp connections to roughly 30Mbit at 4000 connections, their machine panics. An address passed to dma_unmap_single is beyond lowmem, as though it was corrupted in some fashion. The address is the data pointer in the ethernet dma descriptors, it pulls a descriptor out of the ring in the packet receipt functions and at that point the address is wrong. Nowhere in the driver is a descriptor set up with that address, yet the datasheet on the mv643xx doesn't seem to indicate that the dma engine ever writes to the descriptors themselves, only to the data they point to (as you'd expect). Does anyone have any ideas on this? I'm afraid that I'm a bit out of my depth on this issue. The architecture is ppc. Thanks. -- Chris Larson clarson at kergoth dot com clarson at mvista dot com Software Engineer MontaVista Software, Inc.