From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751698AbXC3Nin (ORCPT ); Fri, 30 Mar 2007 09:38:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751498AbXC3Nim (ORCPT ); Fri, 30 Mar 2007 09:38:42 -0400 Received: from mtagate7.de.ibm.com ([195.212.29.156]:19188 "EHLO mtagate7.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751473AbXC3Nik (ORCPT ); Fri, 30 Mar 2007 09:38:40 -0400 Date: Fri, 30 Mar 2007 15:40:42 +0200 From: Cornelia Huck To: Tejun Heo Cc: gregkh@suse.de, hugh@veritas.com, dmitry.torokhov@gmail.com, oneukum@suse.de, maneesh@in.ibm.com, rpurdie@rpsys.net, James.Bottomley@SteelEye.com, Jeff Garzik , lkml , "linux-ide@vger.kernel.org" , SCSI Mailing List Subject: Re: [RFD driver-core] Lifetime problems of the current driver model Message-ID: <20070330154042.4c7deb72@gondolin.boeblingen.de.ibm.com> In-Reply-To: <460D0E78.3040200@gmail.com> References: <460CDBA6.5030608@gmail.com> <20070330151926.18fc12a0@gondolin.boeblingen.de.ibm.com> <460D0E78.3040200@gmail.com> Organization: IBM Deutschland Entwicklung GmbH X-Mailer: Claws Mail 2.8.0 (GTK+ 2.8.20; i486-pc-linux-gnu) X-Legal: IBM Deutschland Entwicklung GmbH Vorsitzender des Aufsichtsrats: Johann Weihen =?ISO-8859-15?Q?Gesch=E4ftsf=FChrung:?= Herbert Kircher Sitz der Gesellschaft: =?ISO-8859-15?Q?B=F6blingen?= Registergericht: Amtsgericht Stuttgart, HRB 243294 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 30 Mar 2007 22:19:52 +0900, Tejun Heo wrote: > > Shouldn't getting/putting the module refcount be solely done in > > kobject.c? Grab the module reference when the kobject is created and > > release the module reference in kobject_cleanup() after the release > > function has been called. This doesn't make kobject_get() heavier, and > > it ensures we don't delete the module until after the last kobject it is > > supposed to clean up has been released. > > If we do that, we wouldn't be able to unload a module if there is any > kobject referencing it even when the node has no openers, so no easy way > out there. :-( But we must not unload the module when there is still a kobject around referencing a release function in the module, or we will oops if the kobject is finally released. If needed, the module must clean up its kobjects in its exit function.