Return-Path: <linux-kernel-owner+w=401wt.eu-S1755375AbYJ3Kz4@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1755375AbYJ3Kz4 (ORCPT <rfc822;w@1wt.eu>);
	Thu, 30 Oct 2008 06:55:56 -0400
Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755040AbYJ3Kzd
	(ORCPT <rfc822;linux-kernel-outgoing>);
	Thu, 30 Oct 2008 06:55:33 -0400
Received: from smtp-vbr6.xs4all.nl ([194.109.24.26]:2361 "EHLO
	smtp-vbr6.xs4all.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1754962AbYJ3Kza (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Thu, 30 Oct 2008 06:55:30 -0400
Date: Thu, 30 Oct 2008 11:55:24 +0100
From: Folkert van Heusden <folkert@vanheusden.com>
To: Kay Sievers <kay.sievers@vrfy.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>, linux-kernel@vger.kernel.org
Subject: Re: [2.6.26] kobject_add_internal failed for 2:0 with -EEXIST /
	unable to handle kernel NULL pointer dereference in
	sysfs_create_link
Message-ID: <20081030105513.GY11214@vanheusden.com>
References: <20081028151157.GI11214@vanheusden.com> <ac3eb2510810281607o19266977l4c77d3d3ab4bb849@mail.gmail.com> <20081029094041.GO11214@vanheusden.com> <ac3eb2510810290525h1579bad8i4836ce1291d9022@mail.gmail.com> <20081029132704.GS11214@vanheusden.com> <ac3eb2510810290749o2dd062b5m7b966d2d25b69714@mail.gmail.com> <20081029152550.GT11214@vanheusden.com> <ac3eb2510810291451u577aa825lc12a7e8fbc213020@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <ac3eb2510810291451u577aa825lc12a7e8fbc213020@mail.gmail.com>
Organization: www.unixexpert.nl
X-Chameleon-Return-To: folkert@vanheusden.com
X-Xfmail-Return-To: folkert@vanheusden.com
X-Phonenumber: +31-6-41278122
X-URL: http://www.vanheusden.com/
X-PGP-KeyID: 1F28D8AE
X-GPG-fingerprint: AC89 09CE 41F2 00B4 FCF2  B174 3019 0E8C 1F28 D8AE
X-Key: http://pgp.surfnet.nl:11371/pks/lookup?op=get&search=0x1F28D8AE
Reply-By: Wed Oct 29 12:57:18 CET 2008
X-Message-Flag: www.vanheusden.com
User-Agent: Mutt/1.5.18 (2008-05-17)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 2931
Lines: 63

> >> >> >> > While running my http://vanheusden.com/pyk/ script (which randomly
> >> >> >> > inserts and removes modules) I triggered the folllowing oops in a 2.6.26
> >> >> >> > kernel on an IBM xSeries 260. This oops (in fact no oops at all) did not
> >> >> >> > get triggered in a 2.6.18 kernel on that system.
> >> >> >> >
> >> >> >> > [   42.507375] FDC 0 is a National Semiconductor PC87306
> >> >> >> > [   42.509057] kobject_add_internal failed for 2:0 with -EEXIST, don't try to register things with the same name in the same directory.
> >> >> >> > [   42.509291] Pid: 5301, comm: modprobe Not tainted 2.6.26-1-amd64 #1
> >> >> >> > [   42.509431]
> >> >> >> > [   42.509433] Call Trace:
> >> >> >> > [   42.509685]  [<ffffffff8031b031>] kobject_add_internal+0x13f/0x17e
> >> > ...
> >> >> >> > [   42.511519]  [<ffffffff8027d23b>] bdi_register+0x57/0xb4
> >> >> >>
> >> >> >> Looks like bdi sees two devices with the same devnum, or didn't
> >> >> >> cleanup an old entry. What does: ls -l "/sys/class/bdi/" print?
> >> >> >
> >> >> > The following:
> >> >> > folkert@debiantesthw:~$ ls -l /sys/class/bdi/
> >> >> > drwxr-xr-x 3 root root 0 2008-10-28 18:32 2:0
> >> >> > drwxr-xr-x 3 root root 0 2008-10-28 18:32 2:1
> >> >>
> >> >> Oh, you are running the old sysfs layout without symlinks. Care to
> >> >> tell where the "device" link in these directories points to?
> >> >
> >> > None exist:
> >> > folkert@debiantesthw:~$ ls -la /sys/class/bdi/*/device
> >> > ls: cannot access /sys/class/bdi/*/device: No such file or directory
> >>
> >> Ah, sorry. Seems the bdi stuff never got to pass the usual parent
> >> device with the device registration, to let the bdi device show up at
> >> the right place in the device tree.
> >>
> >> Let's see what current devices on your box have the major 2:
> >>   find /sys -name dev | xargs grep '^2:'
> >
> > /sys/block/fd0/dev:2:0
> > /sys/block/fd1/dev:2:1
> >
> > As my script does modprobe/rmmod in parallel (4 processes) maybe it is a
> > conflict of one process doing an modprobe of floppy while the other does
> > an rmmod? Or both a modprobe?
> 
> Might be, yes. If you just bootup, and don't run your modprobe/rmmod
> script, does the box have 2 floppy devices in /sys too?

Yes it does. One physical drive.


Folkert van Heusden

-- 
Multitail est un outil permettant la visualisation de fichiers de
journalisation et/ou le suivi de l'ex?cution de commandes. Filtrage,
mise en couleur de mot-cl?, fusions, visualisation de diff?rences
(diff-view), etc.  http://www.vanheusden.com/multitail/
----------------------------------------------------------------------
Phone: +31-6-41278122, PGP-key: 1F28D8AE, www.vanheusden.com
--
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/