From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422663AbWAMNdh (ORCPT ); Fri, 13 Jan 2006 08:33:37 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1422664AbWAMNdg (ORCPT ); Fri, 13 Jan 2006 08:33:36 -0500 Received: from uproxy.gmail.com ([66.249.92.195]:19235 "EHLO uproxy.gmail.com") by vger.kernel.org with ESMTP id S1422662AbWAMNdg convert rfc822-to-8bit (ORCPT ); Fri, 13 Jan 2006 08:33:36 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=AoHRZ1Om3KoDtkqxtjdzg9cvfXVE7XYBvlhqjRN3Oe/AyM+N2GLEJR8rkPbT78ebP8E+2gy/X46kkkXzPrAf02reZTruf+l1EHpGTQiYcXOjtATdzk1HNdBCZw7TPmjjF//ClnSz6crLeadtwCL3X+nlv/JbP+Cn58CLsl3KFp8= Message-ID: <58cb370e0601130533n5842cb5fufc5058f9a1acc606@mail.gmail.com> Date: Fri, 13 Jan 2006 14:33:34 +0100 From: Bartlomiej Zolnierkiewicz To: =?ISO-8859-1?Q?Ville_Syrj=E4l=E4?= Subject: Re: Fwd: ide-cd turning off DMA when verifying DVD-R Cc: Ondrej Zary , Robert Hancock , Volker Kuhlmann , Jens Axboe , linux-ide , linux-kernel In-Reply-To: <20060113112510.GA23264@sci.fi> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Content-Disposition: inline References: <5ujmU-1UQ-665@gated-at.bofh.it> <5uoqr-Qq-7@gated-at.bofh.it> <43C72F41.5060207@shaw.ca> <20060113083009.GE12338@paradise.net.nz> <58cb370e0601130119g5c62b749r1bc5da59a0d4a56c@mail.gmail.com> <58cb370e0601130121s2f6c0a26jda00ff64df197342@mail.gmail.com> <20060113093818.GA22984@sci.fi> <58cb370e0601130149g32323b4axbf0ac55f83ac9148@mail.gmail.com> <20060113112510.GA23264@sci.fi> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org I'm adding missing cc:, I hope I didn't forget about anybody this time. There is now bugzilla entry for this bug (thanks Ondrej): http://bugzilla.kernel.org/show_bug.cgi?id=5882 Jens, could you take a look at the part related to ide-cd timeouts? On 1/13/06, Ville Syrjälä wrote: > On Fri, Jan 13, 2006 at 10:49:22AM +0100, Bartlomiej Zolnierkiewicz wrote: > > On 1/13/06, Ville Syrjälä wrote: > > > On Fri, Jan 13, 2006 at 10:21:44AM +0100, Bartlomiej Zolnierkiewicz wrote: > > > > On 1/13/06, Volker Kuhlmann wrote: > > > > > On Fri 13 Jan 2006 17:40:33 NZDT +1300, Robert Hancock wrote: > > > > > > > > > > > I'm thinking the IDE code is too aggressive in assuming that the failure > > > > > > is because of a DMA problem and disabling it.. Most likely all that's > > > > > > happening is the drive is taking a long time to complete the current > > > > > > command. > > > > > > > > What actually happened is that normal command timed out > > > > and because of that driver reset the device which caused > > > > it to loose DMA: > > > > > > > > ->ide_atapi_error() > > > > ->ide_do_reset() > > > > ->pre_reset() > > > > ->check_dma_crc() > > > > ->__ide_dma_off() > > > > > > > > Somebody needs to investigate why __ide_dma_off() is called > > > > et all and if we need to restore DMA after reset (don't count ATM > > > > on me, I'm buried by bugreports). Ondrej, could you fill the bug at > > > > http://bugzilla.kernel.org so we don't lose it? > > > > > > It looks like this has been fixed recently. In 2.6.14-rc4-mm1 > > > check_dma_crc() used to call __ide_dma_off() when no CRC errors were > > > registered. The bug has been fixed before 2.6.15-rc5-mm1. I'm still > > > running 2.6.14-rc4-mm1 on my burning system so I haven't actually tested > > > this on a recent kernel. > > > > I don't see it being fixed, could you point me at the patch? > > It seems the patch was carried along during the 2.6.15-rc-mm series but > was later dropped. > > Here it is: > http://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.15-rc5/2.6.15-rc5-mm3/broken-out/ide-promise-flushing-hang-fix.patch > > There's a bunch of other stuff in that patch besides the __ide_dma_off() > change. Maybe that approach isn't correct and just increasing some > timeout value would work. LG burners are just really slow recognizing > discs. The patch was NACK-ed by Alan Cox and I agree with him (this should be done differently). This __ide_dma_off() chunk looks sensible but does it fix the issue? I was under impression that after a reset drive looses its DMA xfer mode and needs to be reprogrammed (ATA spec has the answer). > I just took some random discs from my colletion and measured the time it > took for the drive to recognize them. > > ~12 seconds for CD-R > ~15 seconds for some DVD+R > ~27 seconds for some DVD+R > > I'm not sure why it takes so long for some discs. I know they aren't > bad burns because my laptop DVD-ROM drive, which is more sensitive to > disc quality than the LG, can read them without any problems and it > recognizes them in a few seconds. I'll let Jens comment on this one. :) Bartlomiej