Re: [PATCH 2/3] virtio_net: Add the check for vdpa mac address

[Jason Wang]

On Tue, Aug 6, 2024 at 8:58 AM Cindy Lu <lulu@redhat.com> wrote:
>
> When using a VDPA device, this is another acceptable situations
> The hardware MAC address is not 0, and the MAC address in the QEMU command 
> line is 0.
> This is also acceptable
>
> Signed-off-by: Cindy Lu <lulu@redhat.com>
> ---
>  hw/net/virtio-net.c | 13 ++++++++++++-
>  1 file changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> index 7f51bd0dd3..c144ae2e78 100644
> --- a/hw/net/virtio-net.c
> +++ b/hw/net/virtio-net.c
> @@ -3592,11 +3592,22 @@ static bool virtio_net_check_vdpa_mac(NetClientState 
> *nc, VirtIONet *n, MACAddr
>       * 1.The hardware MAC address is the same as the QEMU command line MAC
>       *   address, and both of them are not 0.
>       */
> -
> +       /*
> +     * 2.The hardware MAC address is not 0,
> +     *  and the MAC address in the QEMU command line is 0.
> +     *  In this situation, the hardware MAC address will overwrite
> +     *  the QEMU command line address.

This seems to break libvirt assumption?

Adding Jonathon.

> +     */
>         if (memcmp(&hwcfg.mac, &zero, sizeof(MACAddr)) != 0) {
>                 if ((memcmp(&hwcfg.mac, cmdline_mac, sizeof(MACAddr)) == 0)) {
>                         return true;
>                 }
> +               if (memcmp(cmdline_mac, &zero, sizeof(MACAddr)) == 0) {
> +                       /* overwrite the mac address with hardware address*/
> +                       memcpy(&n->mac[0], &hwcfg.mac, sizeof(n->mac));
> +                       memcpy(&n->nic_conf.macaddr, &hwcfg.mac, 
> sizeof(n->mac));
> +                       return true;
> +               }
>         }
>         error_setg(errp, "vDPA device's mac != the mac address from qemu 
> cmdline"
>                          "Please check the the vdpa device's setting.");
> --
> 2.45.0
>

Thanks