| Message ID | 1453208789-42479-3-git-send-email-imammedo@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 01/19/2016 06:06 AM, Igor Mammedov wrote: > From: Gal Hammer <ghammer@redhat.com> > > Signed-off-by: Gal Hammer <ghammer@redhat.com> > Signed-off-by: Igor Mammedov <imammedo@redhat.com> > --- > docs/specs/vmgenid.txt | 36 ++++++++++++++++++++++++++++++++++++ > 1 file changed, 36 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..718850a > --- /dev/null > +++ b/docs/specs/vmgenid.txt > @@ -0,0 +1,36 @@ > +VIRTUAL MACHINE GENERATION ID > +============================= > + > +Copyright (C) 2014 Red Hat, Inc. Do you want to add 2016? Otherwise, Reviewed-by: Eric Blake <eblake@redhat.com>
On Wed, 20 Jan 2016 09:40:04 -0700 Eric Blake <eblake@redhat.com> wrote: > On 01/19/2016 06:06 AM, Igor Mammedov wrote: > > From: Gal Hammer <ghammer@redhat.com> > > > > Signed-off-by: Gal Hammer <ghammer@redhat.com> > > Signed-off-by: Igor Mammedov <imammedo@redhat.com> > > --- > > docs/specs/vmgenid.txt | 36 ++++++++++++++++++++++++++++++++++++ > > 1 file changed, 36 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..718850a > > --- /dev/null > > +++ b/docs/specs/vmgenid.txt > > @@ -0,0 +1,36 @@ > > +VIRTUAL MACHINE GENERATION ID > > +============================= > > + > > +Copyright (C) 2014 Red Hat, Inc. > > Do you want to add 2016? Sure, I'll fix it up. > > Otherwise, > Reviewed-by: Eric Blake <eblake@redhat.com> >
diff --git a/docs/specs/vmgenid.txt b/docs/specs/vmgenid.txt new file mode 100644 index 0000000..718850a --- /dev/null +++ b/docs/specs/vmgenid.txt @@ -0,0 +1,36 @@ +VIRTUAL MACHINE GENERATION ID +============================= + +Copyright (C) 2014 Red Hat, Inc. + +This work is licensed under the terms of the GNU GPL, version 2 or later. +See the COPYING file in the top-level directory. + +=== + +The VM generation ID (vmgenid) device is an emulated device which +exposes 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). + +This is specified on the web at: http://go.microsoft.com/fwlink/?LinkId=260709 + +--- + +The vmgenid device is a PCI device with the following ACPI ID: "QEMU0003". + +The device has a "vmgenid.uuid" property, which can be set using +the command line argument or the QMP interface. +For example: +QEMU -device vmgenid,id=FOO,uuid="324e6eaf-d1d1-4bf6-bf41-b9bb6c91fb87" + +Or to change uuid in runtime use: + qom-set "/machine/peripheral/FOO.uuid" "124e6eaf-d1d1-4bf6-bf41-b9bb6c91fb87" + +According to the specification, any change to the GUID executes an +ACPI notification. The vmgenid device triggers the \_GPE._E00 handler +which executes the ACPI Notify operation. + +Although not specified in Microsoft's document, it is assumed that the +device is expected to use the little-endian system.