From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031091AbXDQFGl (ORCPT ); Tue, 17 Apr 2007 01:06:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753959AbXDQFGk (ORCPT ); Tue, 17 Apr 2007 01:06:40 -0400 Received: from nz-out-0506.google.com ([64.233.162.226]:38627 "EHLO nz-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753970AbXDQFGj (ORCPT ); Tue, 17 Apr 2007 01:06:39 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:user-agent:mime-version:to:cc:subject:references:in-reply-to:x-enigmail-version:content-type:content-transfer-encoding; b=j49wXaFxSlR0pWh1/1slWiY7GmyA5pWOxZKrvGxjz7uidUchuGYVRayQGv0afv3G2bv4SWH1F2UGRFl3mvd2WXpSFHueEKqYctcONuK4uefd+6nJ3U5PAcPTw0kfrWy3yk3c2VPLTn6Bib1YLsQwYyF2zUS4a/FNf0uRZ66Un1w= Message-ID: <462455D7.3050908@gmail.com> Date: Tue, 17 Apr 2007 14:06:31 +0900 From: Tejun Heo User-Agent: Icedove 1.5.0.10 (X11/20070307) MIME-Version: 1.0 To: maneesh@in.ibm.com CC: gregkh@suse.de, dmitry.torokhov@gmail.com, cornelia.huck@de.ibm.com, oneukum@suse.de, rpurdie@rpsys.net, James.Bottomley@SteelEye.com, stern@rowland.harvard.edu, linux-kernel@vger.kernel.org Subject: Re: [PATCHSET #master] sysfs: make sysfs disconnect immediately on deletion, take 2 References: <11760923261269-git-send-email-htejun@gmail.com> <20070416082212.GC31874@in.ibm.com> In-Reply-To: <20070416082212.GC31874@in.ibm.com> X-Enigmail-Version: 0.94.2.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hello, Maneesh. Maneesh Soni wrote: > I started looking at these patches and parallely also did some testing on a > 8 CPU system. I am using the patches from Greg's tree at > http://www.kernel.org/pub/scm/linux/kernel/git/gregkh/patches.git/ > > I ran following loops parallelly > > # while true; do insmod drivers/net/dummy.ko; sleep 1;rmmod dummy; done > # while true; do find /sys/class/net/dummy0 | xargs cat; sleep 1; done > # while true; do umount /sys; sleep 1; mount -t sysfs none /sys; done > # while true; do find /sys | xargs cat > /dev/null; sleep 1; done > > and got the following oops > > Unable to handle kernel NULL pointer dereference at 000000000000004c RIP: > [] simple_unlink+0x14/0x5c Eeek... I'll try to replicate and track down the bug here. FWIW, SCSI also oopses if udev is running due to a bug in SCSI open/close handling. Thanks for testing. -- tejun