unregister_netdevice: waiting for lo to become free. Usage count = 2
ref_tracker: lo@ffff88802ca645b8 has 1/1 users at
     __netdev_tracker_alloc include/linux/netdevice.h:4110 [inline]
     netdev_hold include/linux/netdevice.h:4139 [inline]
     inetdev_init+0x211/0x4f0 net/ipv4/devinet.c:282
     inetdev_event+0x308/0x15c0 net/ipv4/devinet.c:1568
     notifier_call_chain+0x197/0x390 kernel/notifier.c:93
     call_netdevice_notifiers_extack net/core/dev.c:2090 [inline]
     call_netdevice_notifiers net/core/dev.c:2104 [inline]
     register_netdevice+0x160c/0x1ae0 net/core/dev.c:10344
     register_netdev+0x3b/0x50 net/core/dev.c:10443
     loopback_net_init+0x75/0x150 drivers/net/loopback.c:220
     ops_init+0x397/0x640 net/core/net_namespace.c:139
     setup_net+0x3a5/0xa00 net/core/net_namespace.c:343
     copy_net_ns+0x36d/0x5e0 net/core/net_namespace.c:520
     create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110
     unshare_nsproxy_namespaces+0x11a/0x160 kernel/nsproxy.c:228
     ksys_unshare+0x4c0/0x890 kernel/fork.c:3439
     __do_sys_unshare kernel/fork.c:3510 [inline]
     __se_sys_unshare kernel/fork.c:3508 [inline]
     __x64_sys_unshare+0x38/0x40 kernel/fork.c:3508
     do_syscall_x64 arch/x86/entry/common.c:46 [inline]
     do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
     entry_SYSCALL_64_after_hwframe+0x68/0xd2