------------[ cut here ]------------
ODEBUG: free active (active state 1) object type: rcu_head hint:           (null)
WARNING: CPU: 0 PID: 7536 at lib/debugobjects.c:325 debug_print_object+0x168/0x250 lib/debugobjects.c:325
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 7536 Comm: kworker/0:4 Not tainted 4.19.75 #0
kobject: 'loop0' (0000000038600b71): kobject_uevent_env
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue:            (null) (ipv6_addrconf)
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 panic+0x263/0x507 kernel/panic.c:185
kobject: 'loop0' (0000000038600b71): fill_kobj_path: path = '/devices/virtual/block/loop0'
 __warn.cold+0x20/0x4a kernel/panic.c:540
 report_bug+0x263/0x2b0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 fixup_bug arch/x86/kernel/traps.c:173 [inline]
 do_error_trap+0x204/0x360 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1037
RIP: 0010:debug_print_object+0x168/0x250 lib/debugobjects.c:325
Code: dd 20 56 82 87 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 b5 00 00 00 48 8b 14 dd 20 56 82 87 48 c7 c7 60 4b 82 87 e8 d6 04 19 fe <0f> 0b 83 05 cb 83 17 06 01 48 83 c4 20 5b 41 5c 41 5d 41 5e 5d c3
RSP: 0018:ffff88805719fba0 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8155dbd6 RDI: ffffed100ae33f66
RBP: ffff88805719fbe0 R08: ffff888057190200 R09: ffffed1015d03ee3
R10: ffffed1015d03ee2 R11: ffff8880ae81f717 R12: 0000000000000001
R13: ffffffff8879f200 R14: 0000000000000000 R15: ffff8880530d53a0
 __debug_check_no_obj_freed lib/debugobjects.c:785 [inline]
 debug_check_no_obj_freed+0x29f/0x464 lib/debugobjects.c:817
 kmem_cache_free+0x18f/0x260 mm/slab.c:3764
 free_task_struct kernel/fork.c:162 [inline]
 free_task+0xdd/0x120 kernel/fork.c:416
 __put_task_struct+0x20f/0x4c0 kernel/fork.c:689
 put_task_struct include/linux/sched/task.h:96 [inline]
 finish_task_switch+0x52b/0x780 kernel/sched/core.c:2710
 context_switch kernel/sched/core.c:2829 [inline]
 __schedule+0x86e/0x1dc0 kernel/sched/core.c:3474
 schedule+0x92/0x1c0 kernel/sched/core.c:3518
 worker_thread+0x248/0xe40 kernel/workqueue.c:2317
 kthread+0x354/0x420 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

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