WARNING: CPU: 1 PID: 11921 at kernel/events/core.c:331 event_function_local.constprop.115+0x520/0x5c0 kernel/events/core.c:331
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 11921 Comm: syz-executor4 Not tainted 4.17.0+ #39
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+0x1b9/0x294 lib/dump_stack.c:113
 panic+0x22f/0x4de kernel/panic.c:184
 __warn.cold.8+0x163/0x1b3 kernel/panic.c:536
 report_bug+0x252/0x2d0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x1fc/0x4d0 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992
RIP: 0010:event_function_local.constprop.115+0x520/0x5c0 kernel/events/core.c:331
Code: 00 48 8b 95 70 ff ff ff e9 b8 fc ff ff 48 89 85 70 ff ff ff e8 71 b5 25 00 48 8b 85 70 ff ff ff e9 f6 fc ff ff e8 80 8b e8 ff <0f> 0b e9 6d fe ff ff 48 8b bd 68 ff ff ff e8 6d b5 25 00 48 8d 55 
RSP: 0018:ffff8801daf07cf8 EFLAGS: 00010006
RAX: ffff88019acce700 RBX: ffff8801cea787c0 RCX: ffffffff8191b01a
RDX: 0000000000010000 RSI: ffffffff8191b210 RDI: 0000000000000005
RBP: ffff8801daf07d98 R08: ffff88019acce700 R09: ffffed0039d4f0f9
R10: ffffed0039d4f0f9 R11: ffff8801cea787cb R12: 1ffff1003b5e0fa2
R13: ffff8801daf31a00 R14: ffff88019af32000 R15: ffff8801acbd6580
 perf_event_disable_local kernel/events/core.c:2180 [inline]
 perf_pending_event+0x242/0x2a0 kernel/events/core.c:5811
 irq_work_run_list+0x1b4/0x270 kernel/irq_work.c:155
 irq_work_run+0x1d/0x50 kernel/irq_work.c:170
 smp_irq_work_interrupt+0x10a/0x650 arch/x86/kernel/irq_work.c:21
 irq_work_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
 </IRQ>
RIP: 0010:arch_local_irq_enable arch/x86/include/asm/paravirt.h:793 [inline]
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x56/0x70 kernel/locking/spinlock.c:192
Code: f1 88 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 1d 48 83 3d 3b dc 6e 01 00 74 11 fb 66 0f 1f 44 00 00 <65> ff 0d 83 21 7f 78 5b 5d c3 0f 0b e8 39 9b 34 fa eb dc 0f 1f 80 
RSP: 0018:ffff8801b644fd50 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff09
RAX: dffffc0000000000 RBX: ffff8801cf975c08 RCX: 0000000000000000
RDX: 1ffffffff11e350f RSI: 0000000000000001 RDI: ffffffff88f1a878
RBP: ffff8801b644fd58 R08: ffffed0039f2eb82 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801cf975c08
R13: ffff8801b05da280 R14: ffff8801b05da310 R15: ffff8801b05da31c
 spin_unlock_irq include/linux/spinlock.h:360 [inline]
 do_group_exit+0x357/0x430 kernel/exit.c:965
 __do_sys_exit_group kernel/exit.c:979 [inline]
 __se_sys_exit_group kernel/exit.c:977 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:977
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x455b29
Code: 1d ba 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 eb b9 fb ff c3 66 2e 0f 1f 84 00 00 00 00 
RSP: 002b:00007ffc2d6beb18 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000000000000008c RCX: 0000000000455b29
RDX: 000000000001bd50 RSI: 00000000007310e0 RDI: 0000000000000000
RBP: 0000000000000013 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000013
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000001380

======================================================
WARNING: possible circular locking dependency detected
4.17.0+ #39 Not tainted
------------------------------------------------------
syz-executor4/11921 is trying to acquire lock:
(____ptrval____) ((console_sem).lock){-...}, at: down_trylock+0x13/0x70 kernel/locking/semaphore.c:136

but task is already holding lock:
(____ptrval____) (&ctx->lock){-...}, at: perf_ctx_lock kernel/events/core.c:157 [inline]
(____ptrval____) (&ctx->lock){-...}, at: event_function_local.constprop.115+0x2a3/0x5c0 kernel/events/core.c:318

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&ctx->lock){-...}:
       __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
       _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:144
       perf_event_context_sched_out kernel/events/core.c:3129 [inline]
       __perf_event_task_sched_out+0x12df/0x1a30 kernel/events/core.c:3221
       perf_event_task_sched_out include/linux/perf_event.h:1112 [inline]
       prepare_task_switch kernel/sched/core.c:2637 [inline]
       context_switch kernel/sched/core.c:2823 [inline]
       __schedule+0x1027/0x1e70 kernel/sched/core.c:3500
       schedule+0xef/0x430 kernel/sched/core.c:3544
       freezable_schedule include/linux/freezer.h:172 [inline]
       futex_wait_queue_me+0x3e8/0x820 kernel/futex.c:2530
       futex_wait+0x450/0x9f0 kernel/futex.c:2645
       do_futex+0x336/0x27d0 kernel/futex.c:3527
       __do_sys_futex kernel/futex.c:3587 [inline]
       __se_sys_futex kernel/futex.c:3555 [inline]
       __x64_sys_futex+0x46a/0x680 kernel/futex.c:3555
       do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:290
       entry_SYSCALL_64_after_hwframe+0x49/0xbe

-> #2 (&rq->lock){-.-.}:
       __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
       _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:144
       rq_lock kernel/sched/sched.h:1805 [inline]
       task_fork_fair+0x8a/0x660 kernel/sched/fair.c:9953
       sched_fork+0x43e/0xb30 kernel/sched/core.c:2380
       copy_process.part.38+0x1bf1/0x7180 kernel/fork.c:1765
       copy_process kernel/fork.c:1608 [inline]
       _do_fork+0x291/0x12a0 kernel/fork.c:2091
       kernel_thread+0x34/0x40 kernel/fork.c:2150
       rest_init+0x22/0xe4 init/main.c:408
       start_kernel+0x906/0x92d init/main.c:738
       x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:452
       x86_64_start_kernel+0x76/0x79 arch/x86/kernel/head64.c:433
       secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:242

-> #1 (&p->pi_lock){-.-.}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152
       try_to_wake_up+0xca/0x1280 kernel/sched/core.c:1984
       wake_up_process+0x10/0x20 kernel/sched/core.c:2147
       __up.isra.1+0x1b8/0x290 kernel/locking/semaphore.c:262
       up+0x12f/0x1b0 kernel/locking/semaphore.c:187
       __up_console_sem+0xbe/0x1b0 kernel/printk/printk.c:242
       console_unlock+0x79a/0x10a0 kernel/printk/printk.c:2411
       vprintk_emit+0x6b2/0xde0 kernel/printk/printk.c:1907
       vprintk_default+0x28/0x30 kernel/printk/printk.c:1948
       vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:382
       printk+0x9e/0xba kernel/printk/printk.c:1981
       load_umh+0x51/0xbd net/bpfilter/bpfilter_kern.c:99
       do_one_initcall+0x127/0x913 init/main.c:884
       do_initcall_level init/main.c:952 [inline]
       do_initcalls init/main.c:960 [inline]
       do_basic_setup init/main.c:978 [inline]
       kernel_init_freeable+0x49b/0x58e init/main.c:1135
       kernel_init+0x11/0x1b3 init/main.c:1061
       ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412

-> #0 ((console_sem).lock){-...}:
       lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3924
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152
       down_trylock+0x13/0x70 kernel/locking/semaphore.c:136
       __down_trylock_console_sem+0xae/0x200 kernel/printk/printk.c:225
       console_trylock+0x15/0xa0 kernel/printk/printk.c:2230
       console_trylock_spinning kernel/printk/printk.c:1643 [inline]
       vprintk_emit+0x699/0xde0 kernel/printk/printk.c:1906
       vprintk_default+0x28/0x30 kernel/printk/printk.c:1948
       vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:382
       printk+0x9e/0xba kernel/printk/printk.c:1981
       __warn.cold.8+0x73/0x1b3 kernel/panic.c:518
       report_bug+0x252/0x2d0 lib/bug.c:186
       fixup_bug arch/x86/kernel/traps.c:178 [inline]
       do_error_trap+0x1fc/0x4d0 arch/x86/kernel/traps.c:296
       do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
       invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992
       event_function_local.constprop.115+0x520/0x5c0 kernel/events/core.c:331
       perf_event_disable_local kernel/events/core.c:2180 [inline]
       perf_pending_event+0x242/0x2a0 kernel/events/core.c:5811
       irq_work_run_list+0x1b4/0x270 kernel/irq_work.c:155
       irq_work_run+0x1d/0x50 kernel/irq_work.c:170
       smp_irq_work_interrupt+0x10a/0x650 arch/x86/kernel/irq_work.c:21
       irq_work_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
       arch_local_irq_enable arch/x86/include/asm/paravirt.h:793 [inline]
       __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline]
       _raw_spin_unlock_irq+0x56/0x70 kernel/locking/spinlock.c:192
       spin_unlock_irq include/linux/spinlock.h:360 [inline]
       do_group_exit+0x357/0x430 kernel/exit.c:965
       __do_sys_exit_group kernel/exit.c:979 [inline]
       __se_sys_exit_group kernel/exit.c:977 [inline]
       __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:977
       do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:290
       entry_SYSCALL_64_after_hwframe+0x49/0xbe

other info that might help us debug this:

Chain exists of:
  (console_sem).lock --> &rq->lock --> &ctx->lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ctx->lock);
                               lock(&rq->lock);
                               lock(&ctx->lock);
  lock((console_sem).lock);

 *** DEADLOCK ***

2 locks held by syz-executor4/11921:
 #0: (____ptrval____) (&cpuctx_lock){-...}, at: perf_ctx_lock kernel/events/core.c:155 [inline]
 #0: (____ptrval____) (&cpuctx_lock){-...}, at: event_function_local.constprop.115+0x282/0x5c0 kernel/events/core.c:318
 #1: (____ptrval____) (&ctx->lock){-...}, at: perf_ctx_lock kernel/events/core.c:157 [inline]
 #1: (____ptrval____) (&ctx->lock){-...}, at: event_function_local.constprop.115+0x2a3/0x5c0 kernel/events/core.c:318

stack backtrace:
CPU: 1 PID: 11921 Comm: syz-executor4 Not tainted 4.17.0+ #39
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+0x1b9/0x294 lib/dump_stack.c:113
 print_circular_bug.isra.36.cold.56+0x1bd/0x27d kernel/locking/lockdep.c:1227
 check_prev_add kernel/locking/lockdep.c:1867 [inline]
 check_prevs_add kernel/locking/lockdep.c:1980 [inline]
 validate_chain kernel/locking/lockdep.c:2421 [inline]
 __lock_acquire+0x343e/0x5140 kernel/locking/lockdep.c:3435
 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3924
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152
 down_trylock+0x13/0x70 kernel/locking/semaphore.c:136
 __down_trylock_console_sem+0xae/0x200 kernel/printk/printk.c:225
 console_trylock+0x15/0xa0 kernel/printk/printk.c:2230
 console_trylock_spinning kernel/printk/printk.c:1643 [inline]
 vprintk_emit+0x699/0xde0 kernel/printk/printk.c:1906
 vprintk_default+0x28/0x30 kernel/printk/printk.c:1948
 vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:382
 printk+0x9e/0xba kernel/printk/printk.c:1981
 __warn.cold.8+0x73/0x1b3 kernel/panic.c:518
 report_bug+0x252/0x2d0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x1fc/0x4d0 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992
RIP: 0010:event_function_local.constprop.115+0x520/0x5c0 kernel/events/core.c:331
Code: 00 48 8b 95 70 ff ff ff e9 b8 fc ff ff 48 89 85 70 ff ff ff e8 71 b5 25 00 48 8b 85 70 ff ff ff e9 f6 fc ff ff e8 80 8b e8 ff <0f> 0b e9 6d fe ff ff 48 8b bd 68 ff ff ff e8 6d b5 25 00 48 8d 55 
RSP: 0018:ffff8801daf07cf8 EFLAGS: 00010006
RAX: ffff88019acce700 RBX: ffff8801cea787c0 RCX: ffffffff8191b01a
RDX: 0000000000010000 RSI: ffffffff8191b210 RDI: 0000000000000005
RBP: ffff8801daf07d98 R08: ffff88019acce700 R09: ffffed0039d4f0f9
R10: ffffed0039d4f0f9 R11: ffff8801cea787cb R12: 1ffff1003b5e0fa2
R13: ffff8801daf31a00 R14: ffff88019af32000 R15: ffff8801acbd6580
 perf_event_disable_local kernel/events/core.c:2180 [inline]
 perf_pending_event+0x242/0x2a0 kernel/events/core.c:5811
 irq_work_run_list+0x1b4/0x270 kernel/irq_work.c:155
 irq_work_run+0x1d/0x50 kernel/irq_work.c:170
 smp_irq_work_interrupt+0x10a/0x650 arch/x86/kernel/irq_work.c:21
 irq_work_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
 </IRQ>
RIP: 0010:arch_local_irq_enable arch/x86/include/asm/paravirt.h:793 [inline]
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x56/0x70 kernel/locking/spinlock.c:192
Code: f1 88 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 1d 48 83 3d 3b dc 6e 01 00 74 11 fb 66 0f 1f 44 00 00 <65> ff 0d 83 21 7f 78 5b 5d c3 0f 0b e8 39 9b 34 fa eb dc 0f 1f 80 
RSP: 0018:ffff8801b644fd50 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff09
RAX: dffffc0000000000 RBX: ffff8801cf975c08 RCX: 0000000000000000
RDX: 1ffffffff11e350f RSI: 0000000000000001 RDI: ffffffff88f1a878
RBP: ffff8801b644fd58 R08: ffffed0039f2eb82 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801cf975c08
R13: ffff8801b05da280 R14: ffff8801b05da310 R15: ffff8801b05da31c
 spin_unlock_irq include/linux/spinlock.h:360 [inline]
 do_group_exit+0x357/0x430 kernel/exit.c:965
 ? do_syscall_64+0x92
Lost 82 message(s)!
Shutting down cpus with NMI
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..