From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39242) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z1xWO-0003PC-P3 for qemu-devel@nongnu.org; Mon, 08 Jun 2015 09:55:29 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z1xWJ-0006BZ-2w for qemu-devel@nongnu.org; Mon, 08 Jun 2015 09:55:24 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34260) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z1xWI-0006BC-TJ for qemu-devel@nongnu.org; Mon, 08 Jun 2015 09:55:19 -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 6985296C6 for ; Mon, 8 Jun 2015 13:55:18 +0000 (UTC) Message-ID: <55759EC2.5090802@redhat.com> Date: Mon, 08 Jun 2015 15:55:14 +0200 From: Paolo Bonzini MIME-Version: 1.0 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> In-Reply-To: <55759E0A.3090102@redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH V15 4/5] i386: add a Virtual Machine Generation ID device List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gal Hammer , qemu-devel@nongnu.org Cc: imammedo@redhat.com, mst@redhat.com 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"? Paolo