Comment 3 for bug 1403152

I try to make it reproducable and figured out that the problem is related to use of these kind of
interfaces in a lxc container. The tunnel are working in the running lxc-container but if you stop or reboot the
lxc-container the kernel reports this

unregister_netdevice: waiting for lo to become free.....

here the ip link output in the container

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: ip6tnl0: <NOARP> mtu 1452 qdisc noop state DOWN mode DEFAULT group default
    link/tunnel6 :: brd ::
3: ip6gre0: <NOARP> mtu 1448 qdisc noop state DOWN mode DEFAULT group default
    link/gre6 00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00 brd 00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00
4: gt6nactr01: <POINTOPOINT,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN mode DEFAULT group default
    link/gre6 2a:4:f:89:00:05:17:09:00:00:00:00:00:02:00:01 peer 2a:4:f:8:00:0f:09:97:02:17:01:10:00:59:00:05

or the command which creates this kind of tunnels

ip -6 tunnel add gt6nactr01 mode ip6gre local 2a4:4483:5:1709::2:1 remote 2a4:4494:f:997:217:110:59:5
ip link set mtu 1500 dev gt6nactr01 up
ip addr add 2a04:4454:f:f003::1/64 dev gt6nactr01
ip addr add 169.254.193.1/30 dev gt6nactr01

i attach a dmesg output and hope that you can reproduce the problem.

thx

meno