------------[ cut here ]------------
ODEBUG: free active (active state 1) object type: rcu_head hint:           (null)
WARNING: CPU: 1 PID: 14608 at lib/debugobjects.c:325 debug_print_object+0x168/0x250 lib/debugobjects.c:325
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 14608 Comm: syz-executor.1 Not tainted 4.19.75 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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
 __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
kobject: 'loop5' (000000009372a919): kobject_uevent_env
 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:ffff88805139f000 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000040000 RSI: ffffffff8155dbd6 RDI: ffffed100a273df2
RBP: ffff88805139f040 R08: ffff888098e88540 R09: ffffed1015d23ee3
kobject: 'loop5' (000000009372a919): fill_kobj_path: path = '/devices/virtual/block/loop5'
R10: ffffed1015d23ee2 R11: ffff8880ae91f717 R12: 0000000000000001
R13: ffffffff8879f200 R14: 0000000000000000 R15: ffff88809c66d620
 __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
 schedule_timeout+0x8c8/0xfc0 kernel/time/timer.c:1780
 do_wait_for_common kernel/sched/completion.c:83 [inline]
 __wait_for_common kernel/sched/completion.c:104 [inline]
 wait_for_common kernel/sched/completion.c:115 [inline]
 wait_for_completion_killable+0x2a6/0x500 kernel/sched/completion.c:241
kobject: 'loop0' (000000006c333463): kobject_uevent_env
 __kthread_create_on_node+0x289/0x460 kernel/kthread.c:311
kobject: 'loop0' (000000006c333463): fill_kobj_path: path = '/devices/virtual/block/loop0'
 kthread_create_on_node+0xbb/0xf0 kernel/kthread.c:379
 init_rescuer.part.0+0x7d/0x190 kernel/workqueue.c:4036
 init_rescuer kernel/workqueue.c:4076 [inline]
 __alloc_workqueue_key+0xb8e/0xee0 kernel/workqueue.c:4112
 ucma_open+0x84/0x290 drivers/infiniband/core/ucma.c:1725
 misc_open+0x395/0x4c0 drivers/char/misc.c:141
 chrdev_open+0x245/0x6b0 fs/char_dev.c:423
 do_dentry_open+0x4c3/0x1210 fs/open.c:796
 vfs_open+0xa0/0xd0 fs/open.c:905
 do_last fs/namei.c:3418 [inline]
 path_openat+0x10d7/0x45e0 fs/namei.c:3534
 do_filp_open+0x1a1/0x280 fs/namei.c:3564
 do_sys_open+0x3fe/0x550 fs/open.c:1088
 __do_sys_openat fs/open.c:1115 [inline]
 __se_sys_openat fs/open.c:1109 [inline]
 __x64_sys_openat+0x9d/0x100 fs/open.c:1109
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459a29
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f8073c46c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459a29
RDX: 0000000000000002 RSI: 0000000020000280 RDI: ffffffffffffff9c
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8073c476d4
R13: 00000000004c6497 R14: 00000000004db508 R15: 00000000ffffffff

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