From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40075) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YFqyd-00028q-8t for qemu-devel@nongnu.org; Mon, 26 Jan 2015 16:13:44 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YFqyc-0001Ja-7v for qemu-devel@nongnu.org; Mon, 26 Jan 2015 16:13:43 -0500 Received: from mx1.redhat.com ([209.132.183.28]:52425) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YFqyc-0001JR-14 for qemu-devel@nongnu.org; Mon, 26 Jan 2015 16:13:42 -0500 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id t0QLDeWB024816 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Mon, 26 Jan 2015 16:13:40 -0500 Message-ID: <54C6AE02.4030105@redhat.com> Date: Mon, 26 Jan 2015 16:13:38 -0500 From: Max Reitz MIME-Version: 1.0 References: <1422300468-16216-1-git-send-email-mreitz@redhat.com> <1422300468-16216-5-git-send-email-mreitz@redhat.com> <54C6A622.9010902@redhat.com> <54C6A6E4.8060000@redhat.com> <54C6AD3D.60808@redhat.com> In-Reply-To: <54C6AD3D.60808@redhat.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 04/21] block: Add bdrv_close_all() handlers List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini , qemu-devel@nongnu.org Cc: Kevin Wolf , Markus Armbruster , Stefan Hajnoczi On 2015-01-26 at 16:10, Paolo Bonzini wrote: > > On 26/01/2015 21:43, Max Reitz wrote: >>> If the NBD server is attached to the BDS, it should keep serving the BDS. >> The problem is that it is no longer attached to the BDS, but to the BB. > That's not necessarily a problem. :) It is the cause of the problem though. > > Is it possible to attach two BBs to the same BDS? > > Because part of the solution could be to introduce a new blockdev-serve > command that takes a BDS, creates a BB and exports that BB. > >> I think to retain compatibility we could either just do what we always >> did (although I find it wrong), or we could simply set up an eject >> blocker when attaching an NBD server to a BB. What do you think? > An eject blocker would also break backwards-compatibility though. What > about an eject notifier? Would that concept make sense? It does make sense (in that it is the way I would implement "just do what we always did"), but I just don't like it for the fact that it makes NBD a special snowflake. I can live with it, though. Max