Re: Balloon driver?

Avi Kivity
2007-06-06T17:24:27Z

Carsten Otte wrote:
>
>> So you suggest having a PCI driver that exports a virtio device for
>> each PCI device it matches? Sounds fine to me, though it goes beyond
>> what I think Rusty had in mind with his latest set of virtio
>> patches.
>>
> We don't need a PCI device per virtio device. We can have a PCI device
> that is a virtio bus driver.
>
>

I think it is better to have a pci device per, er, device. It's nice to
be able to do lspci (on an older Linux distro) and see what devices you
have, instead of requiring a new tool. It will also not require us to
backport the virtual bus to older kernels.

Newer kernels can of course use a hypercall-based bus (suggestion: one
hypercall that reads an array of structures, each describing one device,
and one interrupt that means "please issue that hypercall and take
notice of any changes that may have occurred since the last time you did
that").

--
Do not meddle in the internals of kernels, for they are subtle and quick to panic.