------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(class_idx > MAX_LOCKDEP_KEYS)
WARNING: CPU: 0 PID: 15621 at kernel/locking/lockdep.c:3765 __lock_acquire+0x17b5/0x5490 kernel/locking/lockdep.c:3765
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 15621 Comm: syz-executor.4 Not tainted 5.2.0-rc5+ #31
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+0x2cb/0x744 kernel/panic.c:219
 __warn.cold+0x20/0x4d kernel/panic.c:576
 report_bug+0x263/0x2b0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:179 [inline]
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272
 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:986
RIP: 0010:__lock_acquire+0x17b5/0x5490 kernel/locking/lockdep.c:3765
Code: d2 0f 85 c7 2c 00 00 44 8b 3d 27 9e 29 08 45 85 ff 0f 85 57 f3 ff ff 48 c7 c6 20 c5 6b 87 48 c7 c7 00 9c 6b 87 e8 69 d4 eb ff <0f> 0b e9 40 f3 ff ff 0f 0b e9 83 f1 ff ff 8b 0d 47 87 0e 09 85 c9
RSP: 0018:ffff888039637920 EFLAGS: 00010086
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000005a16 RSI: ffffffff815ad926 RDI: ffffed10072c6f16
RBP: ffff888039637ac8 R08: ffff88805d84e500 R09: fffffbfff1173191
R10: fffffbfff1173190 R11: ffffffff88b98c83 R12: 00000000de7db574
R13: 0000000000000000 R14: 00000000000c1574 R15: 0000000000000000
 lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:4303
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline]
 _raw_spin_lock_irq+0x60/0x80 kernel/locking/spinlock.c:167
 spin_lock_irq include/linux/spinlock.h:363 [inline]
 flush_workqueue_prep_pwqs+0x1c5/0x590 kernel/workqueue.c:2729
 flush_workqueue+0x54b/0x14c0 kernel/workqueue.c:2800
 capi20_release+0x1e2/0x280 drivers/isdn/capi/kcapi.c:748
 capi_release+0x1cd/0x230 drivers/isdn/capi/capi.c:975
 __fput+0x2ff/0x890 fs/file_table.c:280
 ____fput+0x16/0x20 fs/file_table.c:313
 task_work_run+0x145/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:185 [inline]
 exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:168
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
 do_syscall_32_irqs_on arch/x86/entry/common.c:352 [inline]
 do_fast_syscall_32+0xb51/0xd7d arch/x86/entry/common.c:408
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f9b849
Code: 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 14 24 c3 8b 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f5d970cc EFLAGS: 00000296 ORIG_RAX: 000000000000003f
RAX: 0000000000000004 RBX: 0000000000000003 RCX: 0000000000000004
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..