This series implements Virtio spec update from Aaron Conole which defines a way for the host to expose its max MTU to the guest.
This third version re-desings how MTU value is provided to QEMU. Now, host_mtu parameter is added to provide QEMU with the MTU value, and the backend, if supported, gets notified of the MTU value when the MTU feature neogotiation succeeds. Only user backend currently supports MTU notification. A new protocol feature has been implemented for sending MTU value to the backend. Aaron, Kevin, Flavio, do you confirm this works for OVS if DPDK vhost lib adds needed API to get the MTU value? For kernel backend, it is expected the management tool also configures the tap/macvtap interface with same MTU value. Daniel, I would be interrested about your feedback on this implementation from management tool point of view. Changes since RFC v2: --------------------- - host_mtu propoerty is now used to specify the MTU value - update vhost-user spec with MTU additions Changes since RFC v1: --------------------- - Rebased on top of v2.8.0-rc0 (2.7.90) - Write MTU unconditionnaly in netcfg to avoid memory leak (Paolo) - Add host_mtu property to be able to disable the feature from QEMU Maxime Coquelin (3): vhost-user: Add MTU protocol feature and op vhost-net: Notify the backend about the host MTU virtio-net: Add MTU feature support docs/specs/vhost-user.txt | 13 +++++++++++++ hw/net/vhost_net.c | 22 ++++++++++++++++++++++ hw/net/virtio-net.c | 13 +++++++++++++ hw/virtio/vhost-user.c | 13 +++++++++++++ include/hw/virtio/vhost-backend.h | 2 ++ include/hw/virtio/virtio-net.h | 1 + include/net/vhost_net.h | 2 ++ 7 files changed, 66 insertions(+) -- 2.9.3