ODEBUG: free active (active state 0) object type: timer_list hint: ip_mc_rejoin_groups net/ipv4/igmp.c:1587 [inline]
ODEBUG: free active (active state 0) object type: timer_list hint: igmp_timer_expire+0x0/0x570 net/ipv4/igmp.c:3010
------------[ cut here ]------------
kobject: 'loop0' (ffff8801d230a3e0): kobject_uevent_env
kobject: 'loop0' (ffff8801d230a3e0): fill_kobj_path: path = '/devices/virtual/block/loop0'
WARNING: CPU: 0 PID: 7 at lib/debugobjects.c:289 debug_print_object+0x17a/0x210 lib/debugobjects.c:286
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 7 Comm: ksoftirqd/0 Not tainted 4.12.0-rc1+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x145/0x1f1 lib/dump_stack.c:52
 panic+0x1b6/0x358 kernel/panic.c:180
 __warn+0x18d/0x1b0 kernel/panic.c:541
 report_bug+0x1a4/0x250 lib/bug.c:183
 fixup_bug arch/x86/kernel/traps.c:190 [inline]
 do_trap_no_signal arch/x86/kernel/traps.c:224 [inline]
 do_trap+0x1d9/0x3e0 arch/x86/kernel/traps.c:273
 do_error_trap+0x120/0x390 arch/x86/kernel/traps.c:310
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:323
 invalid_op+0x1e/0x30 arch/x86/entry/entry_64.S:847
RIP: 0010:debug_print_object+0x17a/0x210 lib/debugobjects.c:286
RSP: 0018:ffff8801d9777700 EFLAGS: 00010082
RAX: 000000000000005e RBX: 0000000000000003 RCX: 0000000000000000
RDX: 000000000000005e RSI: 1ffff1003b2eeea2 RDI: ffffed003b2eeed6
RBP: ffff8801d9777728 R08: 0000000000000000 R09: 1ffff1003b2eee74
R10: ffffed003b2eef0c R11: ffffffff81583bac R12: ffffffff870c7ca0
R13: ffffffff85f0dc70 R14: 0000000000000000 R15: dffffc0000000000
 __debug_check_no_obj_freed lib/debugobjects.c:743 [inline]
 debug_check_no_obj_freed+0x662/0xf20 lib/debugobjects.c:772
 kfree+0xbd/0x270 mm/slab.c:3827
 __rcu_reclaim kernel/rcu/rcu.h:190 [inline]
 rcu_do_batch kernel/rcu/tree.c:2800 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:3057 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:3024 [inline]
 rcu_process_callbacks+0xebd/0x1800 kernel/rcu/tree.c:3041
 __do_softirq+0x300/0xbd3 kernel/softirq.c:284
 run_ksoftirqd+0x86/0x100 kernel/softirq.c:676
 smpboot_thread_fn+0x574/0x900 kernel/smpboot.c:164
 kthread+0x345/0x410 kernel/kthread.c:231
 ret_from_fork+0x31/0x40 arch/x86/entry/entry_64.S:427

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