------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(!test_bit(class_idx, lock_classes_in_use))
WARNING: CPU: 3 PID: 31 at kernel/locking/lockdep.c:4872 __lock_acquire+0xfbf/0x5230 kernel/locking/lockdep.c:4872
Modules linked in:
CPU: 3 PID: 31 Comm: kworker/3:0 Not tainted 5.13.0-rc3-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Workqueue: events l2cap_chan_timeout
RIP: 0010:__lock_acquire+0xfbf/0x5230 kernel/locking/lockdep.c:4872
Code: d2 0f 85 26 36 00 00 44 8b 3d 15 09 70 0c 45 85 ff 0f 85 b1 fd ff ff 48 c7 c6 00 cc 6b 89 48 c7 c7 40 9d 6b 89 e8 3e 88 7b 07 <0f> 0b e9 9a fd ff ff 41 bd 02 00 00 00 e9 32 f6 ff ff 48 c7 c2 20
RSP: 0018:ffffc900005af908 EFLAGS: 00010086
RAX: 0000000000000000 RBX: fffffffffff3e55d RCX: 0000000000000000
RDX: ffff888011e7a180 RSI: ffffffff815c1445 RDI: fffff520000b5f13
RBP: ffff888011e7ac18 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815bb27e R11: 0000000000000000 R12: ffff888011e7a180
R13: ffff888011e7ac3a R14: ffff888011e7ab78 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88802cd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000014a53ad CR3: 0000000067423000 CR4: 0000000000150ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 lock_acquire kernel/locking/lockdep.c:5512 [inline]
 lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5477
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
 _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:175
 spin_lock_bh include/linux/spinlock.h:359 [inline]
 lock_sock_nested+0x40/0x120 net/core/sock.c:3057
 l2cap_sock_teardown_cb+0xa1/0x660 net/bluetooth/l2cap_sock.c:1528
 l2cap_chan_del+0xbc/0xa80 net/bluetooth/l2cap_core.c:622
 l2cap_chan_close+0x1bc/0xaf0 net/bluetooth/l2cap_core.c:825
 l2cap_chan_timeout+0x17e/0x2f0 net/bluetooth/l2cap_core.c:436
 process_one_work+0x98d/0x1600 kernel/workqueue.c:2276
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2422
 kthread+0x3b1/0x4a0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294