[PATCH 1/3] virtio_net: Add the check for vdpa's mac address

[Cindy Lu]

When using a VDPA device, it is important to ensure that
the MAC address in the hardware matches the MAC address
from the QEMU command line.
This will allow the device to boot.

Signed-off-by: Cindy Lu <l...@redhat.com>
---
 hw/net/virtio-net.c | 33 +++++++++++++++++++++++++++++----
 1 file changed, 29 insertions(+), 4 deletions(-)

diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 9c7e85caea..7f51bd0dd3 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -3579,12 +3579,36 @@ 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(NetClientState *nc, VirtIONet *n, 
MACAddr *cmdline_mac,
+                                     Error **errp)
+{
+       struct virtio_net_config hwcfg = {};
+       static const MACAddr zero = { .a = { 0, 0, 0, 0, 0, 0 } };
+
+       vhost_net_get_config(get_vhost_net(nc->peer), (uint8_t *)&hwcfg, 
ETH_ALEN);
+
+    /*
+     * For VDPA device: Only two situations are acceptable:
+     * 1.The hardware MAC address is the same as the QEMU command line MAC
+     *   address, and both of them are not 0.
+     */
+
+       if (memcmp(&hwcfg.mac, &zero, sizeof(MACAddr)) != 0) {
+               if ((memcmp(&hwcfg.mac, cmdline_mac, sizeof(MACAddr)) == 0)) {
+                       return true;
+               }
+       }
+       error_setg(errp, "vDPA device's mac != the mac address from qemu 
cmdline"
+                        "Please check the the vdpa device's setting.");
 
+       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) {
@@ -3692,6 +3716,7 @@ 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;
@@ -3739,10 +3764,10 @@ static void virtio_net_device_realize(DeviceState *dev, 
Error **errp)
     nc->rxfilter_notify_enabled = 1;
 
    if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_VDPA) {
-        struct virtio_net_config netcfg = {};
-        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 (!virtio_net_check_vdpa_mac(nc, n, &macaddr_cmdline, errp)) {
+                  virtio_cleanup(vdev);
+                  return;
+          }
     }
     QTAILQ_INIT(&n->rsc_chains);
     n->qdev = dev;
-- 
2.45.0