Re: [RFC] Unify KVM kernel-space and user-space code into a single project

Daniel P. Berrange
2010-03-22T12:37:26Z

On Mon, Mar 22, 2010 at 02:31:49PM +0200, Pekka Enberg wrote:
> On Mon, Mar 22, 2010 at 1:48 PM, Ingo Molnar <mingo@elte.hu> wrote:
> >> What about line number information?  And the source?  Into the kernel with
> >> them as well?
> >
> > Sigh. Please read the _very first_ suggestion i made, which solves all that. I
> > rarely go into discussions without suggesting technical solutions - i'm not
> > interested in flaming, i'm interested in real solutions.
> >
> > Here it is, repeated for the Nth time:
> >
> > Allow a guest to (optionally) integrate its VFS namespace with the host side
> > as well. An example scheme would be:
> >
> >   /guests/Fedora-G1/
> >   /guests/Fedora-G1/proc/
> >   /guests/Fedora-G1/usr/
> >   /guests/Fedora-G1/.../
> >   /guests/OpenSuse-G2/
> >   /guests/OpenSuse-G2/proc/
> >   /guests/OpenSuse-G2/usr/
> >   /guests/OpenSuse-G2/.../
> >
> >  ( This feature would be configurable and would be default-off, to maintain
> >    the current status quo. )
>
> Heh, funny. That would also solve my number one gripe with
> virtualization these days: how to get files in and out of guests
> without having to install extra packages on the guest side and
> fiddling with mount points on every single guest image I want to play
> with.

FYI, for offline guests, you can use libguestfs[1] to access & change files
inside the guest, and read-only access to running guests files. It provides
access via a interactive shell, APIs in all major languages, and also has a
FUSE mdule to expose it directly in the host VFS. It could probably be made
to work read-write for running guests too if its agent were installed inside
the guest & leverage the new Virtio-Serial channel for comms (avoiding any
network setup requirements).

Regards,
Daniel

[1] http://libguestfs.org/
--
|: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :|
|: http://libvirt.org -o- http://virt-manager.org -o- http://deltacloud.org :|
|: http://autobuild.org -o- http://search.cpan.org/~danberr/ :|
|: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|