From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39486) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YFqvZ-0000Mv-3v for qemu-devel@nongnu.org; Mon, 26 Jan 2015 16:10:34 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YFqvS-0000XR-UW for qemu-devel@nongnu.org; Mon, 26 Jan 2015 16:10:32 -0500 Received: from mail-wi0-x22c.google.com ([2a00:1450:400c:c05::22c]:58431) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YFqvS-0000Wr-Na for qemu-devel@nongnu.org; Mon, 26 Jan 2015 16:10:26 -0500 Received: by mail-wi0-f172.google.com with SMTP id h11so656453wiw.5 for ; Mon, 26 Jan 2015 13:10:26 -0800 (PST) Sender: Paolo Bonzini Message-ID: <54C6AD3D.60808@redhat.com> Date: Mon, 26 Jan 2015 22:10:21 +0100 From: Paolo Bonzini 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> In-Reply-To: <54C6A6E4.8060000@redhat.com> Content-Type: text/plain; charset=windows-1252 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: Max Reitz , qemu-devel@nongnu.org Cc: Kevin Wolf , Markus Armbruster , Stefan Hajnoczi 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? Paolo