unregister_netdevice: waiting for lo to become free. Usage count = 2
ref_tracker: lo@ffff888079cd6608 has 1/1 users at
     __netdev_tracker_alloc include/linux/netdevice.h:4119 [inline]
     netdev_hold include/linux/netdevice.h:4148 [inline]
     dst_init+0xee/0x490 net/core/dst.c:52
     dst_alloc+0x14f/0x190 net/core/dst.c:93
     rt_dst_alloc net/ipv4/route.c:1612 [inline]
     ip_route_input_slow net/ipv4/route.c:2348 [inline]
     ip_route_input_rcu+0x24be/0x3910 net/ipv4/route.c:2463
     ip_route_input_noref+0x167/0x250 net/ipv4/route.c:2473
     ip_rcv_finish_core+0x5b1/0x1b50 net/ipv4/ip_input.c:365
     ip_rcv_finish+0x14a/0x560 net/ipv4/ip_input.c:447
     NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
     __netif_receive_skb_one_core net/core/dev.c:5672 [inline]
     __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5785
     netif_receive_skb_internal net/core/dev.c:5871 [inline]
     netif_receive_skb+0x1e8/0x890 net/core/dev.c:5930
     tun_rx_batched+0x1b7/0x8f0 drivers/net/tun.c:1550
     tun_get_user+0x3056/0x47e0 drivers/net/tun.c:2007
     tun_chr_write_iter+0x10d/0x1f0 drivers/net/tun.c:2053
     new_sync_write fs/read_write.c:586 [inline]
     vfs_write+0xaeb/0xd30 fs/read_write.c:679
     ksys_write+0x18f/0x2b0 fs/read_write.c:731
     do_syscall_x64 arch/x86/entry/common.c:52 [inline]
     do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
     entry_SYSCALL_64_after_hwframe+0x77/0x7f