On Thu, Apr 17, 2025 at 6:25 PM Cindy Lu <l...@redhat.com> wrote:
>
> When using a VDPA device, it is important to ensure that the MAC
> address is correctly set. The MAC address in the hardware should
> match the MAC address from the QEMU command line. This is a recommended
> configuration and will allow the system to boot.
>
> Signed-off-by: Cindy Lu <l...@redhat.com>
> ---
> hw/net/virtio-net.c | 40 +++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 39 insertions(+), 1 deletion(-)
>
> diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> index bd37651dab..0b6a4e5634 100644
> --- a/hw/net/virtio-net.c
> +++ b/hw/net/virtio-net.c
> @@ -3744,12 +3744,29 @@ static bool
> failover_hide_primary_device(DeviceListener *listener,
> /* failover_primary_hidden is set during feature negotiation */
> return qatomic_read(&n->failover_primary_hidden);
> }
> +static bool virtio_net_check_vdpa_mac(VirtIONet *n, uint8_t *hwmac,
> + MACAddr *cmdline_mac, Error **errp)
> +{
> + static const MACAddr zero = { .a = { 0, 0, 0, 0, 0, 0 } };
> +
> + if (memcmp(hwmac, &zero, sizeof(MACAddr)) != 0) {
> + /*
> + * 1. The hardware MAC address is the same as the QEMU command line
> MAC
> + * address, and both of them are not 0.
> + */
> + if ((memcmp(hwmac, cmdline_mac, sizeof(MACAddr)) == 0)) {
> + return true;
> + }
> + }
>
> + return false;
> +}
> static void virtio_net_device_realize(DeviceState *dev, Error **errp)
> {
> VirtIODevice *vdev = VIRTIO_DEVICE(dev);
> VirtIONet *n = VIRTIO_NET(dev);
> NetClientState *nc;
> + MACAddr macaddr_cmdline;
> int i;
>
> if (n->net_conf.mtu) {
> @@ -3857,6 +3874,7 @@ static void virtio_net_device_realize(DeviceState *dev,
> Error **errp)
> virtio_net_add_queue(n, 0);
>
> n->ctrl_vq = virtio_add_queue(vdev, 64, virtio_net_handle_ctrl);
> + memcpy(&macaddr_cmdline, &n->nic_conf.macaddr, sizeof(n->mac));
> qemu_macaddr_default_if_unset(&n->nic_conf.macaddr);
> memcpy(&n->mac[0], &n->nic_conf.macaddr, sizeof(n->mac));
> n->status = VIRTIO_NET_S_LINK_UP;
> @@ -3903,8 +3921,28 @@ static void virtio_net_device_realize(DeviceState
> *dev, Error **errp)
> nc = qemu_get_queue(n->nic);
> nc->rxfilter_notify_enabled = 1;
>
> - if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_VDPA) {
> + if (nc->peer && (nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_VDPA)) {
> +
> struct virtio_net_config netcfg = {};
> + if (nc->peer->check_mac) {
> + vhost_net_get_config(get_vhost_net(nc->peer), (uint8_t *)&netcfg,
> + ETH_ALEN);
> + if (!virtio_net_check_vdpa_mac(n, (uint8_t *)&netcfg.mac,
> + &macaddr_cmdline, errp)) {
> + error_setg(errp, "vDPA device's MAC address "
> + "%02x:%02x:%02x:%02x:%02x:%02x "
> + "is not same as the QEMU command line MAC address"
> + "%02x:%02x:%02x:%02x:%02x:%02x,"
> + "Initialization failed.",
> + netcfg.mac[0], netcfg.mac[1], netcfg.mac[2],
> + netcfg.mac[3], netcfg.mac[4], netcfg.mac[5],
> + macaddr_cmdline.a[0], macaddr_cmdline.a[1],
> + macaddr_cmdline.a[2], macaddr_cmdline.a[3],
> + macaddr_cmdline.a[4], macaddr_cmdline.a[5]);
> + virtio_cleanup(vdev);
> + return;
> + }
> + }
> memcpy(&netcfg.mac, &n->nic_conf.macaddr, ETH_ALEN);
> vhost_net_set_config(get_vhost_net(nc->peer),
> (uint8_t *)&netcfg, 0, ETH_ALEN, VHOST_SET_CONFIG_TYPE_FRONTEND);
If the mac check passes, do we still need to go here to override the
config space which is tricky as some parents doesn't even support set
config.
Thanks
> --
> 2.45.0
>
