syzbot

================================
WARNING: inconsistent lock state
4.19.164-syzkaller #0 Not tainted
--------------------------------
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
swapper/0/0 [HC0[0]:SC1[1]:HE1:SE0] takes:
0000000082a52b3a (slock-AF_BLUETOOTH-BTPROTO_SCO){+.?.}, at: spin_lock include/linux/spinlock.h:329 [inline]
0000000082a52b3a (slock-AF_BLUETOOTH-BTPROTO_SCO){+.?.}, at: sco_sock_timeout+0x31/0x210 net/bluetooth/sco.c:82
{SOFTIRQ-ON-W} state was registered at:
  __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
  _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:144
  spin_lock include/linux/spinlock.h:329 [inline]
  sco_conn_del+0xe2/0x240 net/bluetooth/sco.c:175
  sco_disconn_cfm+0x74/0xb0 net/bluetooth/sco.c:1133
  hci_disconn_cfm include/net/bluetooth/hci_core.h:1261 [inline]
  hci_conn_hash_flush+0x127/0x260 net/bluetooth/hci_conn.c:1512
  hci_dev_do_close+0x659/0xf10 net/bluetooth/hci_core.c:1666
  hci_unregister_dev+0x18b/0x910 net/bluetooth/hci_core.c:3271
  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+0xbed/0x2be0 kernel/exit.c:890
  do_group_exit+0x125/0x310 kernel/exit.c:993
  get_signal+0x3f2/0x1f70 kernel/signal.c:2589
  do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:821
  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
irq event stamp: 1142346
hardirqs last  enabled at (1142346): [<ffffffff81004313>] trace_hardirqs_on_thunk+0x1a/0x1c
hardirqs last disabled at (1142345): [<ffffffff8100432f>] trace_hardirqs_off_thunk+0x1a/0x1c
softirqs last  enabled at (1142334): [<ffffffff813a3acd>] irq_enter+0xbd/0xd0 kernel/softirq.c:354
softirqs last disabled at (1142335): [<ffffffff813a3cf5>] invoke_softirq kernel/softirq.c:372 [inline]
softirqs last disabled at (1142335): [<ffffffff813a3cf5>] irq_exit+0x215/0x260 kernel/softirq.c:412

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(slock-AF_BLUETOOTH-BTPROTO_SCO);
  <Interrupt>
    lock(slock-AF_BLUETOOTH-BTPROTO_SCO);

 *** DEADLOCK ***

1 lock held by swapper/0/0:
 #0: 00000000d9df0ada ((&sk->sk_timer)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:168 [inline]
 #0: 00000000d9df0ada ((&sk->sk_timer)){+.-.}, at: call_timer_fn+0xc9/0x700 kernel/time/timer.c:1328

stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.19.164-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2fe lib/dump_stack.c:118
 print_usage_bug.cold+0x42e/0x570 kernel/locking/lockdep.c:2544
 valid_state kernel/locking/lockdep.c:2557 [inline]
 mark_lock_irq kernel/locking/lockdep.c:2751 [inline]
 mark_lock+0xc70/0x1160 kernel/locking/lockdep.c:3131
 mark_irqflags kernel/locking/lockdep.c:3009 [inline]
 __lock_acquire+0xdc4/0x3ff0 kernel/locking/lockdep.c:3372
 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3907
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:144
 spin_lock include/linux/spinlock.h:329 [inline]
 sco_sock_timeout+0x31/0x210 net/bluetooth/sco.c:82
 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338
 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375
 __run_timers kernel/time/timer.c:1696 [inline]
 run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709
 __do_softirq+0x26c/0x9a0 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:372 [inline]
 irq_exit+0x215/0x260 kernel/softirq.c:412
 exiting_irq arch/x86/include/asm/apic.h:545 [inline]
 smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1094
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
 </IRQ>
RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61
Code: 48 89 df e8 44 1f 85 f9 e9 2e ff ff ff 48 89 df e8 37 1f 85 f9 eb 82 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 14 aa 51 00 fb f4 <c3> 90 e9 07 00 00 00 0f 00 2d 04 aa 51 00 f4 c3 90 90 41 56 41 55
RSP: 0018:ffffffff89e07d40 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff13e3034 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffffffff89e78904
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff89f18190
R13: 1ffffffff13c0fb2 R14: 0000000000000000 R15: 0000000000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
 default_idle+0x49/0x310 arch/x86/kernel/process.c:557
 cpuidle_idle_call kernel/sched/idle.c:153 [inline]
 do_idle+0x2ec/0x4b0 kernel/sched/idle.c:263
 cpu_startup_entry+0xc5/0xe0 kernel/sched/idle.c:369
 start_kernel+0x8d6/0x911 init/main.c:736
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243