From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757927AbXD0XxV (ORCPT ); Fri, 27 Apr 2007 19:53:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757925AbXD0XxV (ORCPT ); Fri, 27 Apr 2007 19:53:21 -0400 Received: from gherkin.frus.com ([192.158.254.49]:50556 "EHLO gherkin.frus.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757922AbXD0XxS (ORCPT ); Fri, 27 Apr 2007 19:53:18 -0400 Subject: Re: BAD_SG_DMA panic in aha1542 In-Reply-To: <1177712499.3688.25.camel@mulgrave.il.steeleye.com> "from James Bottomley at Apr 27, 2007 05:21:39 pm" To: James Bottomley Date: Fri, 27 Apr 2007 18:53:17 -0500 (CDT) CC: linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org X-Mailer: ELM [version 2.4ME+ PL82 (25)] MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII Message-Id: <20070427235317.71B9DDBA2@gherkin.frus.com> From: rct@gherkin.frus.com (Bob Tracy) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org James Bottomley wrote: > On Fri, 2007-04-27 at 16:47 -0500, Bob Tracy wrote: > > I previously reported an ISA DMA issue for the 2.6.12 kernel. The issue > > persists through at least 2.6.18. SCSI controller is an Adaptec > > AHA-1542B (ISA). > > > > The action "mount -t iso9660 /dev/scd0 /mnt/cdrom -r" > > > > produces > > > > (cdrom detection messages as various modules autoload, then...) > > Knowing what these messages are is would be helpful; it tells me what > point in the initialisation it got to. Sorry about that... I'm running the DSL-N distribution (based on Knoppix), and having to transcribe the log messages by hand from the console, i.e., there's no logfile to cut-and-paste from :-(. I don't have access to the machine except on weekdays, but I'll repeat the crash first thing Monday morning and copy everything that's there... > I'm interested. > > This is clearly a use_sg==1 path that has failed to bounce the buffer > for some reason ... and I was contemplating eliminating the GFP_DMA from > our sr driver because I thought the block bouncing had it covered. > > It might also be helpful to apply this patch. It should give a stack > trace of the problem command and not immediately panic the box. I'll throw together a 2.6.21 kernel with this patch and give it a try. Again, it will be at least Monday before you hear back from me on this. Thanks! -- ----------------------------------------------------------------------- Bob Tracy WTO + WIPO = DMCA? http://www.anti-dmca.org rct@frus.com -----------------------------------------------------------------------