unregister_netdevice: waiting for netdevsim0 to become free. Usage count = 2
ref_tracker: netdev@00000000194df2f1 has 1/1 users at
     __netdev_tracker_alloc include/linux/netdevice.h:4346 [inline]
     netdev_tracker_alloc+0x68/0xb4 include/linux/netdevice.h:4358
     fib_create_info+0x22c4/0x2940 net/ipv4/fib_semantics.c:1497
     fib_table_insert+0xac/0x1364 net/ipv4/fib_trie.c:1212
     fib_magic+0x250/0x31c net/ipv4/fib_frontend.c:1133
     fib_add_ifaddr+0x118/0x4f8 net/ipv4/fib_frontend.c:1155
     fib_inetaddr_event+0x114/0x1d0 net/ipv4/fib_frontend.c:1469
     notifier_call_chain+0x1b8/0x4e4 kernel/notifier.c:85
     blocking_notifier_call_chain+0x70/0xa0 kernel/notifier.c:380
     __inet_insert_ifa+0x8d8/0xa98 net/ipv4/devinet.c:567
     inet_rtm_newaddr+0xe10/0x1674 net/ipv4/devinet.c:1002
     rtnetlink_rcv_msg+0x664/0x97c net/core/rtnetlink.c:6946
     netlink_rcv_skb+0x220/0x3fc net/netlink/af_netlink.c:2552
     rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6973
     netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
     netlink_unicast+0x694/0x8c4 net/netlink/af_netlink.c:1346
     netlink_sendmsg+0x648/0x930 net/netlink/af_netlink.c:1896
     sock_sendmsg_nosec net/socket.c:714 [inline]
     __sock_sendmsg net/socket.c:729 [inline]
     __sys_sendto+0x36c/0x4f4 net/socket.c:2228