From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754649AbYIIK30 (ORCPT ); Tue, 9 Sep 2008 06:29:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752110AbYIIK3S (ORCPT ); Tue, 9 Sep 2008 06:29:18 -0400 Received: from pasmtpb.tele.dk ([80.160.77.98]:39793 "EHLO pasmtpB.tele.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751493AbYIIK3S (ORCPT ); Tue, 9 Sep 2008 06:29:18 -0400 Date: Tue, 9 Sep 2008 12:28:45 +0200 From: Jens Axboe To: Elias Oltmanns Cc: FUJITA Tomonori , Greg KH , linux-kernel@vger.kernel.org Subject: Re: Block: Trouble with kobject initialisation for blk_cmd_filter Message-ID: <20080909102844.GD20055@kernel.dk> References: <87od3235fc.fsf@denkblock.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87od3235fc.fsf@denkblock.local> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 05 2008, Elias Oltmanns wrote: > Hi all, > > current usage of the kobject in struct blk_cmd_filter is flawed. Doing > # modprobe -r sd-mod && modprobe sd-mod > while, for instance, a usb-stick is plugged in currently results in > nasty warnings and a dump_stack(). Since blk_cmd_filter is embedded in > struct request_queue, I don't see the need for a kobject anyway. What > about the much simpler option of a struct attribute_group in this > particular case? > > This would imply that the cmd_filter subdirectory would appear under > sda/queue/ rather than sda/ (which is probably the right place) but, > alas, we have to keep compatibility in mind. So I've made some changes > to sysfs along the way in order to provide a legacy symlink. I'd have to > seperate these two changes for submission but I wanted to know your > opinion about it all first. > > Thinking about it now makes me wonder whether this is too much for a rc > patch and whether we should just allocate the struct blk_cmd_filter > dynamically and have done with it. Anyway, tell me what you think. I think this patch is a step in the right direction, lets get rid of that pesky kobject just for the cmdfilter. Can you resend the patch _without_ the sysfs changes and link support? We haven't released a kernel with cmd filter support yet, so we can change the location still and not have to worry about compatability. -- Jens Axboe