From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Artem B. Bityutskiy" Subject: Re: [PATCH 12/16] GFS2: Mounting & sysfs interface Date: Wed, 26 Apr 2006 13:53:00 +0400 Message-ID: <444F42FC.8020306@oktetlabs.ru> References: <1145636505.3856.116.camel@quoit.chygwyn.com> <444E53FC.5060100@oktetlabs.ru> <20060425180433.GA17525@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: Steven Whitehouse , Andrew Morton , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: Received: from [84.204.75.166] ([84.204.75.166]:14305 "EHLO shelob.oktetlabs.ru") by vger.kernel.org with ESMTP id S1751410AbWDZJxC (ORCPT ); Wed, 26 Apr 2006 05:53:02 -0400 To: David Teigland In-Reply-To: <20060425180433.GA17525@redhat.com> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org David Teigland wrote: > On Tue, Apr 25, 2006 at 08:53:16PM +0400, Artem B. Bityutskiy wrote: > >>Hello, >> >>last time I tried to use "bare" sysfs functions to create my sysfs >>hierarchy I ended up with a problem that the module refcount is not >>increased when those sysfs files are opened. So I could open a sysfs >>file from userspace, do rmmod and enjoy oops. >> >>Then I started using the class and class_device stuff, which have an >>.owner field, and all became fine. >> >>I'm not sure if this is a problem of sysfs, but I suspect it could take >>care of module refcount better. >> >>In your patch, I looked for THIS_MODULE pattern and did not find. I did >>not try, but I suspect your code is not devoid of the problem I >>described. So, this is just FYI and may be not the case. > > > Others have also alluded to /sys/fs/ races that we'll probably need to > resolve. In this case the question is more about umount than rmmod since > the mount should reference the module. Right. I just thought you expose sysfs files even if you're not mounted. Sorry, I did not dig deeply. -- Best regards, Artem B. Bityutskiy Oktet Labs (St. Petersburg), Software Engineer. +7 812 4286709 (office) +7 911 2449030 (mobile) E-mail: dedekind@oktetlabs.ru, Web: www.oktetlabs.ru