Re: [PATCH 1/5] virtio-net: Allow setting the MAC address via set_config

[Dor Laor <dlaor@redhat.com>]

Alex Williamson wrote:
> Rename get_config for simplicity
>
> Signed-off-by: Alex Williamson <alex.williamson@hp.com>
> ---
>
>  qemu/hw/virtio-net.c |   18 ++++++++++++++++--
>  1 files changed, 16 insertions(+), 2 deletions(-)
>
> diff --git a/qemu/hw/virtio-net.c b/qemu/hw/virtio-net.c
> index 1f9dc16..e9b3d46 100644
> --- a/qemu/hw/virtio-net.c
> +++ b/qemu/hw/virtio-net.c
> @@ -42,7 +42,7 @@ static VirtIONet *to_virtio_net(VirtIODevice *vdev)
>      return (VirtIONet *)vdev;
>  }
>  
> -static void virtio_net_update_config(VirtIODevice *vdev, uint8_t *config)
> +static void virtio_net_get_config(VirtIODevice *vdev, uint8_t *config)
>  {
>      VirtIONet *n = to_virtio_net(vdev);
>      struct virtio_net_config netcfg;
> @@ -51,6 +51,19 @@ static void virtio_net_update_config(VirtIODevice *vdev, uint8_t *config)
>      memcpy(config, &netcfg, sizeof(netcfg));
>  }
>  
> +static void virtio_net_set_config(VirtIODevice *vdev, const uint8_t *config)
> +{
> +    VirtIONet *n = to_virtio_net(vdev);
> +    struct virtio_net_config netcfg;
> +
> +    memcpy(&netcfg, config, sizeof(netcfg));
> +
> +    if (memcmp(netcfg.mac, n->mac, 6)) {
> +        memcpy(n->mac, netcfg.mac, 6);
> +        qemu_format_nic_info_str(n->vc, n->mac);
> +    }
> +}
> +
>   

What if the guest will chose the host's mac?
Thinking about it, I don't think we should test that.
A concerned host mgmt app can add ebtables roles for such a case.

Maybe we can optionally allow/deny it?