[Lguest] more network interfaces

[Rusty Russell]

On Saturday 15 March 2008 06:15:47 inflo wrote:
> hi,
> i was thinking about more network interfaces inside an guest, i think
> there two ways, one to setup the guest at startup with more network,
> e.g. --tunnet=192.168.3.1;192.168.4.1  but then a guest must be
> restarted if one want more interfaces. So the second one would be a
> hypercall to setup a new field in devices.descpage and call the rest
> stuff like add_lguest_device().
>
> thats my thoughts, some advantages/disadvantages or better ideas are
> welcome.

It sounds suspiciously like a feature, and as we know, features kill puppies!

However, it's possible to add device hotplug to lguest, which would solve this 
problem in general and demonstrate how to do it.  Linux certainly has the 
infrastructure; we just need to use it, and that's not entirely trivial.

It would involve modifying the lguest device array, notifying the guest and 
waiting for some acknowledgement.  The bigger feature addition is actually 
providing a control fd to command the Launcher, currently we don't have such 
a thing, although other features seem to also want it.

IOW, I'm always happy to review patches, but I won't promise to apply them!

Cheers,
Rusty.