unregister_netdevice: waiting for lo to become free. Usage count = 2
ref_tracker: netdev@ffff8880441f2610 has 1/1 users at
     dst_init+0xd9/0x450
     dst_alloc+0x12a/0x170
     ip_route_input_rcu+0x1ed5/0x2ff0
     ip_route_input_noref+0x167/0x250
     ip_rcv_finish_core+0x5af/0x1c00
     ip_rcv_finish+0x14c/0x2f0
     NF_HOOK+0x30c/0x3a0
     __netif_receive_skb+0x143/0x380
     netif_receive_skb+0x1cb/0x790
     tun_rx_batched+0x1b9/0x730
     tun_get_user+0x2aa2/0x3e20
     tun_chr_write_iter+0x113/0x200
     vfs_write+0x5c9/0xb30
     ksys_write+0x145/0x250
     do_syscall_64+0xfa/0x3b0
     entry_SYSCALL_64_after_hwframe+0x77/0x7f

