unregister_netdevice: waiting for lo to become free. Usage count = 2
ref_tracker: netdev@ffff888037ac4658 has 1/1 users at
     __netdev_tracker_alloc include/linux/netdevice.h:4471 [inline]
     netdev_hold include/linux/netdevice.h:4500 [inline]
     dst_init+0xda/0x5b0 net/core/dst.c:52
     dst_alloc+0xbb/0x1a0 net/core/dst.c:94
     rt_dst_alloc+0x35/0x3a0 net/ipv4/route.c:1651
     ip_route_input_slow+0x15b8/0x3fa0 net/ipv4/route.c:2429
     ip_route_input_rcu net/ipv4/route.c:2543 [inline]
     ip_route_input_noref+0x122/0x2e0 net/ipv4/route.c:2554
     ip_rcv_finish_core+0x459/0x2c30 net/ipv4/ip_input.c:407
     ip_rcv_finish net/ipv4/ip_input.c:490 [inline]
     NF_HOOK include/linux/netfilter.h:318 [inline]
     NF_HOOK include/linux/netfilter.h:312 [inline]
     ip_rcv+0x1c0/0x3c0 net/ipv4/ip_input.c:612
     __netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:6202
     __netif_receive_skb+0x1f/0x120 net/core/dev.c:6315
     netif_receive_skb_internal net/core/dev.c:6401 [inline]
     netif_receive_skb+0x13b/0x7f0 net/core/dev.c:6460
     tun_rx_batched.isra.0+0x3f6/0x750 drivers/net/tun.c:1511
     tun_get_user+0x1e31/0x3c20 drivers/net/tun.c:1955
     tun_chr_write_iter+0xdc/0x200 drivers/net/tun.c:2001
     new_sync_write fs/read_write.c:595 [inline]
     vfs_write+0x6ac/0x1070 fs/read_write.c:688
     ksys_write+0x12a/0x250 fs/read_write.c:740
     do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
     do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94