Re: [PATCH] vhost: introduce mdev based hardware backend

Michael S. Tsirkin
2019-09-26T13:26:39Z

On Thu, Sep 26, 2019 at 09:14:39PM +0800, Tiwei Bie wrote:
> > 4. Does device need to limit max ring size?
> > 5. Does device need to limit max number of queues?
>
> I think so. It's helpful to have ioctls to report the max
> ring size and max number of queues.

Also, let's not repeat the vhost net mistakes, let's lock
everything to the order required by the virtio spec,
checking status bits at each step.
E.g.:
set backend features
set features
detect and program vqs
enable vqs
enable driver

and check status at each step to force the correct order.
e.g. don't allow enabling vqs after driver ok, etc

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MST