Virtio driver not compliant with latest specification

[cryslith]

The virtio_net driver included in snabb has not been updated to the Virtio 1.0 specification. This means that virtio devices will eventually stop supporting it as they drop legacy driver support.

I believe my current VM setup does not work for this reason:

Host:

Linux 4.9.0-3-amd64 #1 SMP Debian 4.9.30-2+deb9u3 (2017-08-06) x86_64 GNU/Linux
QEMU emulator version 2.8.1(Debian 1:2.8+dfsg-6+deb9u2)

Guest:

Linux 4.9.0-3-amd64 #1 SMP Debian 4.9.30-2+deb9u3 (2017-08-06) x86_64 GNU/Linux

[dpino]

The virtio_net driver was mostly tested using QEMU v2.4 + SnabbNFV on the host side. Then on the guest side there's no requirements. As far as I recall, other users have reported the virtio_net driver was not working when using other hypervisors, or even with QEMU versions higher than 2.6.

My suggestion is, if possible, to use QEMU v2.4 + SnabbNFV on the host side.

[dpino]

PR https://github.com/snabbco/snabb/pull/1369 fixes vhost-user driver for QEMU >v2.8. Likely this was the reason of the error. FWIW, the virtio-net driver is still working as tested in https://github.com/Igalia/snabb/pull/1165.