Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751934AbZIUQxU (ORCPT ); Mon, 21 Sep 2009 12:53:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751529AbZIUQxU (ORCPT ); Mon, 21 Sep 2009 12:53:20 -0400 Received: from mail09.linbit.com ([212.69.161.110]:34189 "EHLO mail09.linbit.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751476AbZIUQxT (ORCPT ); Mon, 21 Sep 2009 12:53:19 -0400 Date: Mon, 21 Sep 2009 18:53:21 +0200 From: Lars Ellenberg To: Arjan van de Ven Cc: FUJITA Tomonori , lmb@suse.de, jens.axboe@oracle.com, neilb@suse.de, hch@infradead.org, James.Bottomley@suse.de, linux-kernel@vger.kernel.org, drbd-dev@lists.linbit.com, akpm@linux-foundation.org, bart.vanassche@gmail.com, davej@redhat.com, gregkh@suse.de, kosaki.motohiro@jp.fujitsu.com, kyle@moffetthome.net, torvalds@linux-foundation.org, nab@linux-iscsi.org, knikanth@suse.de, philipp.reisner@linbit.com, sam@ravnborg.org, Mauelshagen@redhat.com Subject: Re: [GIT PULL] DRBD for 2.6.32 Message-ID: <20090921165321.GJ8072@barkeeper1-xen.linbit> Mail-Followup-To: Arjan van de Ven , FUJITA Tomonori , lmb@suse.de, jens.axboe@oracle.com, neilb@suse.de, hch@infradead.org, James.Bottomley@suse.de, linux-kernel@vger.kernel.org, drbd-dev@lists.linbit.com, akpm@linux-foundation.org, bart.vanassche@gmail.com, davej@redhat.com, gregkh@suse.de, kosaki.motohiro@jp.fujitsu.com, kyle@moffetthome.net, torvalds@linux-foundation.org, nab@linux-iscsi.org, knikanth@suse.de, philipp.reisner@linbit.com, sam@ravnborg.org, Mauelshagen@RedHat.com References: <20090918200803.GM23126@kernel.dk> <20090919141334N.fujita.tomonori@lab.ntt.co.jp> <20090919220232.GB31849@suse.de> <20090921223815U.fujita.tomonori@lab.ntt.co.jp> <20090921144308.GG8072@barkeeper1-xen.linbit> <20090921165252.04e335b1@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090921165252.04e335b1@infradead.org> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1554 Lines: 44 On Mon, Sep 21, 2009 at 04:52:52PM +0200, Arjan van de Ven wrote: > On Mon, 21 Sep 2009 16:43:08 +0200 > Lars Ellenberg wrote: > > We can choose whatever user-kernel interface you like, > > and change it with every dot release -- > > we'd just need to add additional compat code into > > the drbdsetup userland binary. > > uh no. > > the kernel<->userspace ABI is stable. > we don't go about randomly changing it > (extending it is fine obviously) That's not what I meant, of course that is and needs to be stable. Sorry, I exagerated to make a point. Point was: mdadm configured md. dmsetup configured dm. drbdsetup configure drbd. If and when "something" is done to "unify" things on the implementation level, it is likely to also unify the "kernel<->userspace" configuration interface. If it happens, once that happens, that _will_ be an ABI break. One way to go about it would be to just do that excellently designed and generic and extensible and whatnot new kernel<->userspace thing, and add the necessary compat cruft to the above mentioned configuration tools. Doing the drbdsetup part of it would be our part, which we would gladly accept. Not speaking that not yet designed all-new unified config interface is not a valid argument against DRBD inclusion. Lars -- 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/