From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40448) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z1xZz-0004OR-4J for qemu-devel@nongnu.org; Mon, 08 Jun 2015 09:59:09 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z1xZs-0000tV-2G for qemu-devel@nongnu.org; Mon, 08 Jun 2015 09:59:07 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47638) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z1xZr-0000sy-UI for qemu-devel@nongnu.org; Mon, 08 Jun 2015 09:59:00 -0400 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 (Postfix) with ESMTPS id 704A632E3BB for ; Mon, 8 Jun 2015 13:58:59 +0000 (UTC) Date: Mon, 8 Jun 2015 14:58:54 +0100 From: "Daniel P. Berrange" Message-ID: <20150608135854.GC19157@redhat.com> References: <1430133591-6197-1-git-send-email-ghammer@redhat.com> <1430133591-6197-5-git-send-email-ghammer@redhat.com> <556F2D51.2000203@redhat.com> <55759BB8.3010604@redhat.com> <55759C1B.7000905@redhat.com> <55759E0A.3090102@redhat.com> <55759EC2.5090802@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <55759EC2.5090802@redhat.com> Subject: Re: [Qemu-devel] [PATCH V15 4/5] i386: add a Virtual Machine Generation ID device Reply-To: "Daniel P. Berrange" List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: Gal Hammer , imammedo@redhat.com, qemu-devel@nongnu.org, mst@redhat.com On Mon, Jun 08, 2015 at 03:55:14PM +0200, Paolo Bonzini wrote: > > > On 08/06/2015 15:52, Gal Hammer wrote: > >>> 2. Is it possible to create a sysbus device using the "-device" command > >>> line argument? I vaguely recall that it is not possible to do it and > >>> that's the reason that I specifically add the device in the pc init. > >> > >> It's now possible, but it is somewhat complicated. I think it's simpler > >> to initialize this unconditionally and hide it (via ACPI _STA) if the > >> vmgenid is all zeros. > > > > I didn't understand. I need the device to be a sysbus device so it won't > > be found as an ISA or a PCI device by Windows. So I need to know what > > ever or not it is possible to create a sysbus device using "-device". In > > either way it won't be created if vmgenid is not given so no need to > > hide it using _STA. > > Windows doesn't enumerate ISA devices when you create them with -device. > It just enumerates devices from the ACPI DSDT/SSDT. So it's okay to > make it an ISADevice, or to make it a part of another device (e.g. the > ISA bridge or the power management device). It's still ugly though. > > If you make it a sysbus device, you can just add it unconditionally, and > define _STA so that Windows only sees it under the appropriate > circumstances: for example, return 0 from _STA if the vmgenid (from the > command line) is all zeroes. > > What is the command line option like? Is it "-global vmgenid.uuid=foo"? FWIW, although the spec for this feature comes from Windows/Microsoft, I'd expect that when we enable it in libvirt, we'll want to make it unconditionally available to all VMs, since its a generically useful information source for guest OS'. Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|