Re: [Qemu-devel] [PATCH v3 2/2] vhost user: Add RARP injection for legacy guest

[Michael S. Tsirkin]

On Mon, Jun 15, 2015 at 02:12:40PM +0200, Thibaut Collet wrote:
> After a resume operation the guest always kicks the backend for each
> virtual queues.
> A live migration does a suspend operation on the old host and a resume
> operation on the new host. So the backend has a kick after migration.
> 
> I have checked this point with a legacy guest (redhat 6-5 with kernel
> version 2.6.32-431.29.2) and the kick occurs after migration or
> resume.
> 
> Jason have you an example of legacy guest that will not kick the
> virtual queue after a resume ?

In practice with sufficiently modern guests you can look
at DRIVER_OK status bit. Process rings if that bit is set.

-- 
MST