[PATCH v6 4/4] virtio_net: Add third acceptable configuration for MAC setup.

[Cindy Lu]

For VDPA devices, Allow configurations where both the hardware MAC address
and QEMU command line MAC address are zero.

Signed-off-by: Cindy Lu <l...@redhat.com>
---
 hw/net/virtio-net.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 45b63eb9de..6c6bd116f7 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -3784,6 +3784,18 @@ static bool virtio_net_check_vdpa_mac(NetClientState 
*nc, VirtIONet *n,
             return true;
         }
     }
+    /*
+     * 3. The hardware MAC address is 0,
+     *  and the MAC address in the QEMU command line is also 0.
+     *  In this situation, QEMU generates a random MAC address and
+     *  uses CVQ/set_config to assign it to the device.
+     */
+    if ((memcmp(&hwcfg.mac, &zero, sizeof(MACAddr)) == 0) &&
+        (memcmp(cmdline_mac, &zero, sizeof(MACAddr)) == 0)) {
+        memcpy(&n->mac[0], &n->nic_conf.macaddr, sizeof(n->mac));
+
+        return true;
+    }
     error_setg(errp,
                "vDPA device's MAC address %02x:%02x:%02x:%02x:%02x:%02x "
                "is not the same as the QEMU command line MAC address "
-- 
2.45.0