Whatever version landed in next, according to bisect this broke libvirt/kvms use of bridges: # virsh start s31128001 error: Failed to start domain 's31128001' error: Unable to add bridge virbr1 port vnet0: Operation not supported # grep vnet0 /var/log/libvirt/libvirtd.log 2021-04-21 07:43:09.453+0000: 2460: info : virNetDevTapCreate:240 : created device: 'vnet0' 2021-04-21 07:43:09.453+0000: 2460: debug : virNetDevSetMACInternal:287 : SIOCSIFHWADDR vnet0 MAC=fe:bb:83:28:01:02 - Success 2021-04-21 07:43:09.453+0000: 2460: error : virNetDevBridgeAddPort:633 : Unable to add bridge virbr1 port vnet0: Operation not supported 2021-04-21 07:43:09.466+0000: 2543: debug : udevHandleOneDevice:1695 : udev action: 'add': /sys/devices/virtual/net/vnet0 Christian
