bond0 (unregistering): Releasing backup interface bond_slave_1
bond0 (unregistering): Releasing backup interface bond_slave_0
bond0 (unregistering): Released all slaves
ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x90 kernel/workqueue.c:4806
------------[ cut here ]------------
WARNING: CPU: 0 PID: 8059 at lib/debugobjects.c:291 debug_print_object.cold.14+0xa7/0xdb lib/debugobjects.c:288
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 8059 Comm: kworker/u4:6 Not tainted 4.14.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x145/0x1e1 lib/dump_stack.c:52
 panic+0x1a9/0x34e kernel/panic.c:181
 __warn.cold.8+0x11a/0x156 kernel/panic.c:542
 report_bug+0x1a3/0x227 lib/bug.c:183
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_trap_no_signal arch/x86/kernel/traps.c:212 [inline]
 do_trap+0x1ef/0x2d0 arch/x86/kernel/traps.c:261
 do_error_trap+0x11f/0x390 arch/x86/kernel/traps.c:298
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:311
 invalid_op+0x18/0x20 arch/x86/entry/entry_64.S:905
RIP: 0010:debug_print_object.cold.14+0xa7/0xdb lib/debugobjects.c:288
RSP: 0018:ffff88010da7ea58 EFLAGS: 00010082
RAX: 0000000000000061 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000061 RSI: ffffffff878bd580 RDI: ffffed0021b4fd42
RBP: ffff88010da7ea80 R08: 1ffff10021b4fcd9 R09: ffff88010bb42440
R10: 0000000000000000 R11: dffffc0000000000 R12: ffffffff878b8780
R13: ffffffff81453770 R14: 0000000000000000 R15: ffff88010da7ec28
 __debug_check_no_obj_freed lib/debugobjects.c:745 [inline]
 debug_check_no_obj_freed+0x643/0xcc3 lib/debugobjects.c:774
 kfree+0xbd/0x270 mm/slab.c:3819
 kvfree+0x2c/0x30 mm/util.c:416
 netdev_freemem+0x47/0x60 net/core/dev.c:7975
 netdev_release+0x6a/0x80 net/core/net-sysfs.c:1492
 device_release+0x134/0x170 drivers/base/core.c:814
 kobject_cleanup lib/kobject.c:648 [inline]
 kobject_release lib/kobject.c:677 [inline]
 kref_put include/linux/kref.h:70 [inline]
 kobject_put+0x107/0x1b0 lib/kobject.c:694
 netdev_run_todo+0x883/0xb70 net/core/dev.c:7880
 rtnl_unlock+0x9/0x10 net/core/rtnetlink.c:106
 default_device_exit_batch+0x3d0/0x500 net/core/dev.c:8664
 ops_exit_list.isra.8+0xd3/0x120 net/core/net_namespace.c:145
 cleanup_net+0x55b/0xaa0 net/core/net_namespace.c:483
 process_one_work+0x9f7/0x1a80 kernel/workqueue.c:2119
 worker_thread+0x215/0x1820 kernel/workqueue.c:2253
 kthread+0x376/0x440 kernel/kthread.c:231
 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431

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