unregister_netdevice: waiting for netdevsim1 to become free. Usage count = 2
ref_tracker: netdev@0000000069dd6439 has 1/1 users at
     __netdev_tracker_alloc include/linux/netdevice.h:4471 [inline]
     netdev_tracker_alloc include/linux/netdevice.h:4483 [inline]
     netdev_get_by_index+0x84/0xdc net/core/dev.c:1027
     fib6_nh_init+0x258/0x14f0 net/ipv6/route.c:3613
     ip6_route_info_create_nh+0x13c/0x98c net/ipv6/route.c:3912
     addrconf_f6i_alloc+0x1e4/0x3b4 net/ipv6/route.c:4704
     ipv6_add_addr+0x484/0xdb0 net/ipv6/addrconf.c:1126
     addrconf_add_linklocal+0x1e0/0x378 net/ipv6/addrconf.c:3311
     addrconf_addr_gen+0x27c/0x2dc net/ipv6/addrconf.c:-1
     addrconf_init_auto_addrs+0x390/0x764 net/ipv6/addrconf.c:-1
     addrconf_notify+0x7a0/0xbe8 net/ipv6/addrconf.c:3752
     notifier_call_chain+0x1a4/0x624 kernel/notifier.c:85
     raw_notifier_call_chain+0x3c/0x50 kernel/notifier.c:453
     call_netdevice_notifiers_info+0xb8/0x120 net/core/dev.c:2249
     call_netdevice_notifiers_extack net/core/dev.c:2287 [inline]
     call_netdevice_notifiers net/core/dev.c:2301 [inline]
     __dev_notify_flags+0x160/0x27c net/core/dev.c:9797
     netif_change_flags+0xd0/0x15c net/core/dev.c:9826
     do_setlink+0xc28/0x31e8 net/core/rtnetlink.c:3181
     rtnl_changelink net/core/rtnetlink.c:3800 [inline]
     __rtnl_newlink net/core/rtnetlink.c:3973 [inline]
     rtnl_newlink+0xd24/0x1144 net/core/rtnetlink.c:4110

netdevsim netdevsim2 netdevsim0 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0