[Qemu-devel] guest agent vs. host->guest "environment variables"

[Gabriel L. Somlo]

Hi,

I'm looking for an equivalent to VMWare "guestinfo" variables
(the stuff one may set on a VM via e.g. the vSphere client, under
Summary->Annotations->Notes, and looks like a bunch of "name = value"
environment variable definitions. These can then be retrieved from
the guest via 'vmtoolsd --cmd "info-get guestinfo.name"', which would
print the string "value" to stdout.

After some initial digging, it appears that the QEMU guest agent is
the closest thing to "vmtoolsd" right now, but it doesn't look like
it supports the functionality I'm interested in.

My question is, am I missing anything obvious? Is there anything in
the kvm/qemu/libvirt universe that currently offers this type of
functionality? If not, would it be of any interest? I'm willing (and
hopefully able) to send patches, if it comes to that :)

Also, while extracting this type of "environment variable" on the
guest seems perfectly suited to something like qga, it also appears
that injecting them on the host side might involve cooperation from
a higher layer, such as libvirt.

Any pointers, ideas and tips much appreciated (even just "directions"
to a more appropriate mailing list)...

Thanks much,
--Gabriel