From qemu's point of view these are still just tap devices, so there's no reason they shouldn't work with vhost-net; as a matter of fact, Raja Sivaramakrishnan <srajag00@yahoo.com> verified on libvir-list that at least the qemu_command.c part of this patch works:

https://www.redhat.com/archives/libvir-list/2012-December/msg01314.html (the hotplug case is extrapolation on my part). --- src/qemu/qemu_command.c | 1 + src/qemu/qemu_hotplug.c | 3 +++ 2 files changed, 4 insertions(+) diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index 33f2ecd..6c28123 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -6159,6 +6159,7 @@ qemuBuildCommandLine(virConnectPtr conn, if (actualType == VIR_DOMAIN_NET_TYPE_NETWORK || actualType == VIR_DOMAIN_NET_TYPE_BRIDGE || + actualType == VIR_DOMAIN_NET_TYPE_ETHERNET || actualType == VIR_DOMAIN_NET_TYPE_DIRECT) { /* Attempt to use vhost-net mode for these types of network device */ diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c index 4504f0b..0c28a6a 100644 --- a/src/qemu/qemu_hotplug.c +++ b/src/qemu/qemu_hotplug.c @@ -754,6 +754,9 @@ int qemuDomainAttachNetDevice(virConnectPtr conn, iface_connected = true; if (qemuOpenVhostNet(vm->def, net, priv->qemuCaps, &vhostfd) < 0) goto cleanup; + } else if (actualType == VIR_DOMAIN_NET_TYPE_ETHERNET) { + if (qemuOpenVhostNet(vm->def, net, priv->qemuCaps, &vhostfd) < 0) + goto cleanup; } if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_NET_NAME) || -- 1.7.11.7