From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:49839) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SCCZA-0002pg-Ej for qemu-devel@nongnu.org; Mon, 26 Mar 2012 12:14:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SCCZ4-0003t5-0r for qemu-devel@nongnu.org; Mon, 26 Mar 2012 12:14:43 -0400 Received: from mx1.redhat.com ([209.132.183.28]:6259) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SCCZ3-0003sv-P9 for qemu-devel@nongnu.org; Mon, 26 Mar 2012 12:14:37 -0400 Date: Mon, 26 Mar 2012 13:14:23 -0300 From: Eduardo Habkost Message-ID: <20120326161423.GP9375@otherpad.lan.raisama.net> References: <4F6F1C32.7090801@codemonkey.ws> <4F6F1ED2.6090301@redhat.com> <4F6F2D7D.70500@codemonkey.ws> <4F6F2FB4.5060405@redhat.com> <4F6F32B8.7050401@codemonkey.ws> <4F6F36C7.8010206@redhat.com> <4F6F3941.6040800@codemonkey.ws> <20120326112430.GA150306@orkuz.home> <4F705A09.5070601@redhat.com> <20120326120321.GO22368@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120326120321.GO22368@redhat.com> Subject: Re: [Qemu-devel] [libvirt] Modern CPU models cannot be used with libvirt List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gleb Natapov Cc: libvir-list@redhat.com, Avi Kivity , Anthony Liguori , qemu-devel@nongnu.org On Mon, Mar 26, 2012 at 02:03:21PM +0200, Gleb Natapov wrote: > On Mon, Mar 26, 2012 at 01:59:05PM +0200, Avi Kivity wrote: > > On 03/26/2012 01:24 PM, Jiri Denemark wrote: > > > ... > > > > > The command line becomes unstable if you use -nodefconfig. > > > > > > > > -no-user-config solves this but I fully expect libvirt would continue to use > > > > -nodefconfig. > > > > > > Libvirt uses -nodefaults -nodefconfig because it wants to fully control how > > > the virtual machine will look like (mainly in terms of devices). In other > > > words, we don't want any devices to just magically appear without libvirt > > > knowing about them. -nodefaults gets rid of default devices that are built > > > directly in qemu. Since users can set any devices or command line options > > > (such as enable-kvm) into qemu configuration files in @SYSCONFDIR@, we need to > > > avoid reading those files as well. Hence we use -nodefconfig. However, we > > > would still like qemu to read CPU definitions, machine types, etc. once they > > > become externally loaded configuration (or however we decide to call it). That > > > said, when CPU definitions are moved into @DATADIR@, and -no-user-config is > > > introduced, I don't see any reason for libvirt to keep using -nodefconfig. ACK. > > > > > > I actually like > > > -no-user-config > > > more than > > > -nodefconfig -readconfig @DATADIR@/... > > > since it would avoid additional magic to detect what files libvirt should > > > explicitly pass to -readconfig but basically any approach that would allow us > > > to do read files only from @DATADIR@ is much better than what we have with > > > -nodefconfig now. > > > > That's how I see it as well. > > > +1 > > except that instead of -no-user-config we can do what most other > programs do. If config file is specified during invocation default one > is not used. After implementing -no-user-config (or similar) we can drop > -nodefconfig entirely since its only user will be gone it its semantics > is not clear. Awesome. It looks like we have a solution now? Anthony, do you agree with that? Daniel, it looks good for you? It looks like in the end, no one will ever use -nodefconfig because it's optimizing for a use-case that nobody cares about. Maybe I'm wrong and somebody somewhere will use -nodefconfig, maybe Anthony has a specific use-case or specific tools in mind, I don't know. But personally I will probably simply ignore the existence of -nodefconfig because it is absolutely useless for me and for libvirt. -- Eduardo