From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965282AbXAKAx3 (ORCPT ); Wed, 10 Jan 2007 19:53:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965285AbXAKAx3 (ORCPT ); Wed, 10 Jan 2007 19:53:29 -0500 Received: from wx-out-0506.google.com ([66.249.82.233]:20643 "EHLO wx-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965282AbXAKAx3 (ORCPT ); Wed, 10 Jan 2007 19:53:29 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=XLS+3vJtqYf/poNW6FH3dcf7LdQfpV0Qu3eM0DUYixC4KJ/SMEZtzsbXvO+pWS3B+7jUO+IPEXXWPuG8c+sWCOIwn91K96pBE3igaMmH6svejOTIQikczUrU9yeZY9b5YHe4fohs9e4XhfFxzzHUe1v+p3ONOYQ2r4SZWckpT9A= Message-ID: <948ae28c0701101653n572d0c63n2145e9b4208a6e5b@mail.gmail.com> Date: Wed, 10 Jan 2007 17:53:28 -0700 From: "meaty biscuit" To: linux-kernel@vger.kernel.org Subject: Fwd: DMA problems in ide-scsi In-Reply-To: <948ae28c0701101559j1e750d61g1f810feb04c1c4fb@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <948ae28c0701101559j1e750d61g1f810feb04c1c4fb@mail.gmail.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org I know there are lots of people that are glad to be done with ide-scsi, but I'm hoping there is someone out there that has some experience with this driver that my be able to help. I would happily switch modules and start using ide-cd, but I have a few pieces of software that rely on ide-scsi to work properly and I don't have enough time to change my software to work with ide-cd before my product release deadline. I am working with a mainline kernel, version 2.6.15.7 (I cannot change kernel versions either). If DMA is enabled and I try to write to a CD, I get a kernel panic. However, reading from a CD with DMA enabled works fine. If DMA is disabled and programmed IO is used, I can both read and write CDs but the fact that PIO uses so much of the CPU causes my application to have some problems and again, I don't have time to go through several application release cycles to make them work with PIO. I have noticed that writing to CD (with DMA enabled) in 2.6.9 works fine, it seems as though the breakage of ide-scsi occured in 2.6.10. Also, burning a CD using DMA with ide-scsi in 2.6.19 seems to work as well. I have looked through the ide-scsi code for hours, and I have also done a fair amount of debugging looking for the problem but I have had no success. I tried contacting Bartlomiej and have been unsuccessful in getting a hold of him. Does anyone know of a patch floating around that may fix this problem? Does anyone that is more familiar with the ide, scsi, or dma subsystems have any suggestions for me? I am willing to put in the time and effort to fix this problem and I would be more than happy to submit a fix back into the open source world, but I am stuck and need any help I can get. Thanks for your time.