Re: [Qemu-devel] live migration vs device assignment (motivation)

[Dong, Eddie]

> >
> > Even if the device driver doesn't support migration, you still want to
> > migrate VM? That maybe risk and we should add the "bad path" for the
> > driver at least.
> 
> At a minimum we should have support for hot-plug if we are expecting to
> support migration.  You would simply have to hot-plug the device before you
> start migration and then return it after.  That is how the current bonding
> approach for this works if I am not mistaken.

Hotplug is good to eliminate the device spefic state clone, but bonding 
approach is very network specific, it doesn’t work for other devices such as 
FPGA device, QaT devices & GPU devices, which we plan to support gradually :)

> 
> The advantage we are looking to gain is to avoid removing/disabling the
> device for as long as possible.  Ideally we want to keep the device active
> through the warm-up period, but if the guest doesn't do that we should still
> be able to fall back on the older approaches if needed.
>