syzbot

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ODEBUG: assert_init not available (active state 0) object type: timer_list hint:           (null)
WARNING: CPU: 0 PID: 18570 at lib/debugobjects.c:325 debug_print_object+0x160/0x250 lib/debugobjects.c:325
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 18570 Comm: syz-executor.0 Not tainted 4.19.211-syzkaller #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+0x1fc/0x2ef lib/dump_stack.c:118
 panic+0x26a/0x50e kernel/panic.c:186
 __warn.cold+0x20/0x5a kernel/panic.c:541
 report_bug+0x262/0x2b0 lib/bug.c:183
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 fixup_bug arch/x86/kernel/traps.c:173 [inline]
 do_error_trap+0x1d7/0x310 arch/x86/kernel/traps.c:296
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1038
RIP: 0010:debug_print_object+0x160/0x250 lib/debugobjects.c:325
Code: dd 20 f1 b3 88 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 bf 00 00 00 48 8b 14 dd 20 f1 b3 88 48 c7 c7 40 e5 b3 88 e8 65 92 7b 04 <0f> 0b 83 05 73 e6 af 07 01 48 83 c4 20 5b 5d 41 5c 41 5d c3 48 89
RSP: 0018:ffff88805bca7590 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff814dff01 RDI: ffffed100b794ea4
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000005 R11: ffffffff8c66501b R12: ffffffff89f90a40
R13: ffffffff815313f0 R14: ffff8880b37d9028 R15: 1ffff1100b794ebd
 debug_object_assert_init lib/debugobjects.c:694 [inline]
 debug_object_assert_init+0x1f0/0x2e0 lib/debugobjects.c:665
 debug_timer_assert_init kernel/time/timer.c:733 [inline]
 debug_assert_init kernel/time/timer.c:785 [inline]
 del_timer+0x6d/0x100 kernel/time/timer.c:1210
 try_to_grab_pending+0x2b6/0x6f0 kernel/workqueue.c:1224
 __cancel_work kernel/workqueue.c:3101 [inline]
 cancel_delayed_work+0x76/0x2c0 kernel/workqueue.c:3130
 l2cap_clear_timer include/net/bluetooth/l2cap.h:834 [inline]
 l2cap_chan_del+0x5b4/0xa50 net/bluetooth/l2cap_core.c:645
 l2cap_conn_del+0x3a6/0x6e0 net/bluetooth/l2cap_core.c:1733
 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7445 [inline]
 l2cap_disconn_cfm+0x98/0xd0 net/bluetooth/l2cap_core.c:7438
 hci_disconn_cfm include/net/bluetooth/hci_core.h:1263 [inline]
 hci_conn_hash_flush+0x127/0x260 net/bluetooth/hci_conn.c:1512
 hci_dev_do_close+0x6bc/0x1020 net/bluetooth/hci_core.c:1687
 hci_unregister_dev+0x14f/0x460 net/bluetooth/hci_core.c:3288
 vhci_release+0x70/0xe0 drivers/bluetooth/hci_vhci.c:354
 __fput+0x2ce/0x890 fs/file_table.c:278
 task_work_run+0x148/0x1c0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xbf3/0x2be0 kernel/exit.c:870
 do_group_exit+0x125/0x310 kernel/exit.c:967
 get_signal+0x3f2/0x1f70 kernel/signal.c:2589
 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:799
 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f7175257ae9
Code: Bad RIP value.
RSP: 002b:00007f71741cd218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f717536af68 RCX: 00007f7175257ae9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f717536af68
RBP: 00007f717536af60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f717536af6c
R13: 00007ffce3ef06bf R14: 00007f71741cd300 R15: 0000000000022000
Kernel Offset: disabled
Rebooting in 86400 seconds..