Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262154AbVAJIpO (ORCPT ); Mon, 10 Jan 2005 03:45:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262156AbVAJIpN (ORCPT ); Mon, 10 Jan 2005 03:45:13 -0500 Received: from ns.virtualhost.dk ([195.184.98.160]:63114 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id S262154AbVAJIpI (ORCPT ); Mon, 10 Jan 2005 03:45:08 -0500 Date: Mon, 10 Jan 2005 09:45:06 +0100 From: Jens Axboe To: Alan Cox Cc: Hikaru1@verizon.net, Linux Kernel Mailing List Subject: Re: PROBLEM: ide-cd in 2.6.8-2.6.10 and 2.4.26-2.4.28 high cpu use with dma Message-ID: <20050110084501.GA31651@suse.de> References: <20050109105201.GB12497@roll> <20050109105418.GD12497@roll> <20050109123028.GA12753@roll> <1105278277.12004.32.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1105278277.12004.32.camel@localhost.localdomain> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 939 Lines: 22 On Sun, Jan 09 2005, Alan Cox wrote: > On Sul, 2005-01-09 at 12:30, Hikaru1@verizon.net wrote: > > A minor mistake. I forgot to state explicitly that the problem only appears > > with writing audio cds. Writing data cds does not cause problems. > > It sets the required alignment of buffers for DMA. The 2.6.10 code is > correct, the question is who is feeding unaligned buffers to the driver > layer - the kernel or the SG layer. Which burning interface are you > using - /dev/sg (ie dev=1,0,0) or /dev/hd* (dev=/dev/hdc etc) Look at the check, it's also doing length check. And for cdda burning, you are never going to have 32-byte alignment, hence it false back to pio. -- Jens Axboe - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/