From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755379Ab2LLAle (ORCPT ); Tue, 11 Dec 2012 19:41:34 -0500 Received: from smtprelay.restena.lu ([158.64.1.62]:38145 "EHLO smtprelay.restena.lu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754025Ab2LLAld (ORCPT ); Tue, 11 Dec 2012 19:41:33 -0500 Date: Wed, 12 Dec 2012 01:41:09 +0100 From: Bruno =?UTF-8?B?UHLDqW1vbnQ=?= To: Jacek Poplawski Cc: linux-kernel@vger.kernel.org Subject: Re: "attempt to access beyond end of device" on DVD Message-ID: <20121212014109.38e18eeb@neptune.home> In-Reply-To: References: X-Mailer: Claws Mail 3.8.1 (GTK+ 2.24.12; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Mon, 10 December 2012 Jacek Poplawski wrote: > few years ago I noticed annoying bug on Linux, when I was copying > photos from old DVDs I realized that not all files were copied > correctly, there were errors on last files on DVD, you could say "well > that happens, DVD are faulty", but that's not the real issue > > when the problem appears it happens on each DVD I am trying to copy, > last files on each disk have errors.... > > ...until I reboot Linux, then there are no errors at all and full DVD > is copied correctly. > > Now I needed some files from DVDs and I realized the problem still > exists. After at least three years. I verified that reboot helps and I > also noticed the problem doesn't exist on Windows 7. > > And looks like I wasn't only one who found this: > > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/404472 > > Problem was reported in 2009 on 2.6.28 and closed in 2012. But I > noticed it in last days. > > my system is: > > Linux version 3.6.8-1-ARCH (tobias@T-POWA-LX) (gcc version 4.7.2 (GCC) > ) #1 SMP PREEMPT Mon Nov 26 22:10:40 CET 2012 > > dmesg: > > [ 4017.384169] attempt to access beyond end of device > [ 4017.384171] sr0: rw=0, want=8511124, limit=8433216 > [ 4017.384174] attempt to access beyond end of device > [ 4017.384175] sr0: rw=0, want=8510876, limit=8433216 > > I suspect that people just stopped using CDs and DVDs and that's why > nobody was looking on this problem, or maybe the first though was > always "that DVD is broken, trash it". > > Is there more information I could give you about this issue? Or could > you point me to any ways I could debug it? It's fully reproducible on > my system. Hm, could it be related to some kind of read-ahead? I vaguely remember seeing mails about read-ahead and/or end-of-device. Could this be somehow related? See: - https://lkml.org/lkml/2012/12/3/497 - https://lkml.org/lkml/2012/12/3/510 This applies to 3.7-rc but according to the thread it might still have some interesting things that could be related to what you are seeing. When it happens, does ejecting and re-inserting the CDs/DVDs also fix the problem or is a full reboot mandatory? Bruno