Re: [PATCH RFC 0/3] io_uring: add restrictions to support untrusted applications and guests

[Konrad Rzeszutek Wilk]

.snip..
> Just to recap the proposal, the idea is to add some restrictions to the
> operations (sqe, register, fixed file) to safely allow untrusted applications
> or guests to use io_uring queues.

Hi!

This is neat and quite cool - but one thing that keeps nagging me is
what how much overhead does this cut from the existing setup when you use
virtio (with guests obviously)? That is from a high level view the
beaty of io_uring being passed in the guest is you don't have the
virtio ring -> io_uring processing, right?

Thanks!