Re: [PATCH V3 0/7] mdev based hardware virtio offloading support

From: Stefan Hajnoczi
Date: Mon Oct 14 2019 - 13:49:58 EST

On Fri, Oct 11, 2019 at 04:15:50PM +0800, Jason Wang wrote:
> There are hardware that can do virtio datapath offloading while having
> its own control path. This path tries to implement a mdev based
> unified API to support using kernel virtio driver to drive those
> devices. This is done by introducing a new mdev transport for virtio
> (virtio_mdev) and register itself as a new kind of mdev driver. Then
> it provides a unified way for kernel virtio driver to talk with mdev
> device implementation.
> Though the series only contains kernel driver support, the goal is to
> make the transport generic enough to support userspace drivers. This
> means vhost-mdev[1] could be built on top as well by resuing the
> transport.
> A sample driver is also implemented which simulate a virito-net
> loopback ethernet device on top of vringh + workqueue. This could be
> used as a reference implementation for real hardware driver.
> Consider mdev framework only support VFIO device and driver right now,
> this series also extend it to support other types. This is done
> through introducing class id to the device and pairing it with
> id_talbe claimed by the driver. On top, this seris also decouple
> device specific parents ops out of the common ones.

I was curious so I took a quick look and posted comments.

I guess this driver runs inside the guest since it registers virtio

If this is used with physical PCI devices that support datapath
offloading then how are physical devices presented to the guest without


Attachment: signature.asc
Description: PGP signature