unregister_netdevice: waiting for lo to become free. Usage count = 2
ref_tracker: netdev@ffff88801f6ee610 has 1/1 users at
     __netdev_tracker_alloc include/linux/netdevice.h:4349 [inline]
     netdev_hold include/linux/netdevice.h:4378 [inline]
     dst_init+0xd9/0x450 net/core/dst.c:52
     dst_alloc+0x12a/0x170 net/core/dst.c:93
     rt_dst_alloc net/ipv4/route.c:1645 [inline]
     ip_route_input_slow net/ipv4/route.c:2423 [inline]
     ip_route_input_rcu+0x1ed5/0x2ff0 net/ipv4/route.c:2537
     ip_route_input_noref+0x167/0x250 net/ipv4/route.c:2548
     ip_rcv_finish_core+0x5af/0x1c00 net/ipv4/ip_input.c:371
     ip_rcv_finish+0x14c/0x2f0 net/ipv4/ip_input.c:452
     NF_HOOK+0x309/0x3a0 include/linux/netfilter.h:318
     __netif_receive_skb_one_core net/core/dev.c:5991 [inline]
     __netif_receive_skb+0x143/0x380 net/core/dev.c:6104
     netif_receive_skb_internal net/core/dev.c:6190 [inline]
     netif_receive_skb+0x1cb/0x790 net/core/dev.c:6249
     tun_rx_batched+0x1b9/0x730 drivers/net/tun.c:1485
     tun_get_user+0x2aa2/0x3e20 drivers/net/tun.c:1950
     tun_chr_write_iter+0x113/0x200 drivers/net/tun.c:1996
     new_sync_write fs/read_write.c:593 [inline]
     vfs_write+0x5c6/0xb30 fs/read_write.c:686
     ksys_write+0x145/0x250 fs/read_write.c:738
     do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
     do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
     entry_SYSCALL_64_after_hwframe+0x77/0x7f