From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757896AbXF0Hrm (ORCPT ); Wed, 27 Jun 2007 03:47:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755338AbXF0Hre (ORCPT ); Wed, 27 Jun 2007 03:47:34 -0400 Received: from srv5.dvmed.net ([207.36.208.214]:38408 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752335AbXF0Hrd (ORCPT ); Wed, 27 Jun 2007 03:47:33 -0400 Message-ID: <46821613.9010305@garzik.org> Date: Wed, 27 Jun 2007 03:47:31 -0400 From: Jeff Garzik User-Agent: Thunderbird 1.5.0.12 (X11/20070530) MIME-Version: 1.0 To: Andrew Morton CC: Linus Torvalds , linux-ide@vger.kernel.org, LKML Subject: Re: [git patches] libata fixes References: <20070627073526.GA18787@havoc.gtf.org> <20070627003841.68fd0ea9.akpm@linux-foundation.org> In-Reply-To: <20070627003841.68fd0ea9.akpm@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -4.3 (----) X-Spam-Report: SpamAssassin version 3.1.9 on srv5.dvmed.net summary: Content analysis details: (-4.3 points, 5.0 required) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andrew Morton wrote: > On Wed, 27 Jun 2007 03:35:26 -0400 Jeff Garzik wrote: > >> + /* Don't allow DMA if it isn't multiple of 16 bytes. Quite a >> + * few ATAPI devices choke on such DMA requests. >> + */ >> + if (unlikely(qc->nbytes & 15)) >> + return 1; > > It might be worth emitting a diagnostic when this happens. I tend to disagree, but if any screaming users show up, we can certainly think about adding some. Such would be a diagnostic that would trigger on valid SCSI commands, when the user is doing nothing wrong and the system can indeed complete the command just fine. Additionally, this is moving us in the direction of what the IDE driver has apparently been doing. Jeff