From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60195) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xpwsk-0006hG-9t for qemu-devel@nongnu.org; Sun, 16 Nov 2014 05:16:40 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Xpwsd-000596-5h for qemu-devel@nongnu.org; Sun, 16 Nov 2014 05:16:34 -0500 Received: from mx1.redhat.com ([209.132.183.28]:43080) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xpwsc-00058y-US for qemu-devel@nongnu.org; Sun, 16 Nov 2014 05:16:27 -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 sAGAGQ6n009838 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Sun, 16 Nov 2014 05:16:26 -0500 From: Gal Hammer Date: Sun, 16 Nov 2014 12:15:57 +0200 Message-Id: <1416132959-25905-2-git-send-email-ghammer@redhat.com> In-Reply-To: <1416132959-25905-1-git-send-email-ghammer@redhat.com> References: <1416132959-25905-1-git-send-email-ghammer@redhat.com> Subject: [Qemu-devel] [PATCH 1/3] docs: vm generation id device's description List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Gal Hammer , pbonzini@redhat.com, mst@redhat.com Signed-off-by: Gal Hammer --- docs/specs/vmgenid.txt | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) create mode 100644 docs/specs/vmgenid.txt diff --git a/docs/specs/vmgenid.txt b/docs/specs/vmgenid.txt new file mode 100644 index 0000000..9a09d11 --- /dev/null +++ b/docs/specs/vmgenid.txt @@ -0,0 +1,27 @@ +VIRTUAL MACHINE GENERATION ID +============================= + +The VM generation ID (vmgenid) device is an emulated device which +expose a 128-bit, cryptographically random, integer value identifier. +This allows management applications (e.g. libvirt) to notify the guest +operating system when the virtual machine is executed with a different +configuration (e.g. snapshot execution or creation from a template). + +Specs is on the web at: http://go.microsoft.com/fwlink/?LinkId=260709 + +--- + +The vmgenid device is a sysbus device with the following ACPI ID: +"QEMU0002". + +The device adds a "vmgenid.uuid" property, which can be modifed using +the -global command line argument or the QMP interface. + +The device uses a fixed memory resource: 0xfedf0000-0xfedf0003. The +guest is expected to write the physical address of the GUID's buffer +to that memory resource. This allows the device to modify the GUID if +requested by the management application. + +According to the specification, any change to the GUID executes an +ACPI notification. The vmgenid device triggers the GPE._E00 which +executes the ACPI Notify operation. -- 1.9.3