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possible deadlock in perf_trace_destroy (2)

Status: fixed on 2018/04/24 21:47
Subsystems: trace
[Documentation on labels]
Reported-by: syzbot+c9695f0404c72c8f0b7abbac660d986af9008fc5@syzkaller.appspotmail.com
Fix commit: 82d94856fa22 perf/core: Fix lock inversion between perf,trace,cpuhp
First crash: 2910d, last: 2822d
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
possible deadlock in perf_trace_destroy (2) 6 (7) 2018/04/21 17:12
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in perf_trace_destroy (3) trace 4 12 2504d 2633d 0/29 auto-closed as invalid on 2019/06/14 09:18
android-414 possible deadlock in perf_trace_destroy 4 1 2601d 2601d 0/1 auto-closed as invalid on 2019/03/09 03:11
android-414 possible deadlock in perf_trace_destroy (2) 4 1 2391d 2385d 0/1 auto-closed as invalid on 2019/10/05 09:33
upstream possible deadlock in perf_trace_destroy trace 4 C 525 2929d 2913d 0/29 closed as invalid on 2017/11/01 19:39
linux-4.14 possible deadlock in perf_trace_destroy 4 C inconclusive 829 1972d 2384d 0/1 upstream: reported C repro on 2019/04/15 13:38

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
4.15.0-rc8+ #2 Not tainted
------------------------------------------------------
syzkaller107260/3655 is trying to acquire lock:
 (event_mutex){+.+.}, at: [<0000000078168e26>] perf_trace_destroy+0x28/0x100 kernel/trace/trace_event_perf.c:234

but task is already holding lock:
 (&event->child_mutex){+.+.}, at: [<00000000501d8b43>] perf_event_release_kernel+0x2ea/0xc10 kernel/events/core.c:4260

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #5 (&event->child_mutex){+.+.}:
       __mutex_lock_common kernel/locking/mutex.c:756 [inline]
       __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893
       mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
       perf_event_for_each_child+0x8a/0x150 kernel/events/core.c:4557
       perf_event_for_each kernel/events/core.c:4574 [inline]
       _perf_ioctl kernel/events/core.c:4734 [inline]
       perf_ioctl+0x46b/0x1430 kernel/events/core.c:4748
       vfs_ioctl fs/ioctl.c:46 [inline]
       do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
       SYSC_ioctl fs/ioctl.c:701 [inline]
       SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
       entry_SYSCALL_64_fastpath+0x29/0xa0

-> #4 (&cpuctx_mutex){+.+.}:
       __mutex_lock_common kernel/locking/mutex.c:756 [inline]
       __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893
       mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
       perf_event_init_cpu+0xb6/0x160 kernel/events/core.c:11076
       perf_event_init+0x4e9/0x549 kernel/events/core.c:11123
       start_kernel+0x4cc/0x819 init/main.c:627
       x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:378
       x86_64_start_kernel+0x77/0x7a arch/x86/kernel/head64.c:359
       secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:237

-> #3 (pmus_lock){+.+.}:
       __mutex_lock_common kernel/locking/mutex.c:756 [inline]
       __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893
       mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
       perf_event_init_cpu+0x2f/0x160 kernel/events/core.c:11070
       cpuhp_invoke_callback+0x2ea/0x1d20 kernel/cpu.c:182
       cpuhp_up_callbacks kernel/cpu.c:477 [inline]
       _cpu_up+0x216/0x510 kernel/cpu.c:1036
       do_cpu_up+0x73/0xa0 kernel/cpu.c:1066
       cpu_up+0x18/0x20 kernel/cpu.c:1074
       smp_init+0x13a/0x152 kernel/smp.c:578
       kernel_init_freeable+0x2fe/0x521 init/main.c:1067
       kernel_init+0x13/0x180 init/main.c:999
       ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:541

-> #2 (cpu_hotplug_lock.rw_sem){++++}:
       percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline]
       percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
       cpus_read_lock+0x42/0x90 kernel/cpu.c:293
       static_key_slow_inc+0x9d/0x3c0 kernel/jump_label.c:123
       tracepoint_add_func kernel/tracepoint.c:223 [inline]
       tracepoint_probe_register_prio+0x80d/0x9a0 kernel/tracepoint.c:283
       tracepoint_probe_register+0x2a/0x40 kernel/tracepoint.c:304
       trace_event_reg+0x167/0x320 kernel/trace/trace_events.c:305
       perf_trace_event_reg kernel/trace/trace_event_perf.c:122 [inline]
       perf_trace_event_init kernel/trace/trace_event_perf.c:197 [inline]
       perf_trace_init+0x4ef/0xab0 kernel/trace/trace_event_perf.c:221
       perf_tp_event_init+0x7d/0xf0 kernel/events/core.c:7959
       perf_try_init_event+0xc9/0x1f0 kernel/events/core.c:9192
       perf_init_event kernel/events/core.c:9230 [inline]
       perf_event_alloc+0x1cc6/0x2b00 kernel/events/core.c:9494
       SYSC_perf_event_open+0x84e/0x2e00 kernel/events/core.c:9949
       SyS_perf_event_open+0x39/0x50 kernel/events/core.c:9835
       entry_SYSCALL_64_fastpath+0x29/0xa0

-> #1 (tracepoints_mutex){+.+.}:
       __mutex_lock_common kernel/locking/mutex.c:756 [inline]
       __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893
       mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
       tracepoint_probe_register_prio+0xa0/0x9a0 kernel/tracepoint.c:279
       tracepoint_probe_register+0x2a/0x40 kernel/tracepoint.c:304
       trace_event_reg+0x167/0x320 kernel/trace/trace_events.c:305
       perf_trace_event_reg kernel/trace/trace_event_perf.c:122 [inline]
       perf_trace_event_init kernel/trace/trace_event_perf.c:197 [inline]
       perf_trace_init+0x4ef/0xab0 kernel/trace/trace_event_perf.c:221
       perf_tp_event_init+0x7d/0xf0 kernel/events/core.c:7959
       perf_try_init_event+0xc9/0x1f0 kernel/events/core.c:9192
       perf_init_event kernel/events/core.c:9230 [inline]
       perf_event_alloc+0x1cc6/0x2b00 kernel/events/core.c:9494
       SYSC_perf_event_open+0x84e/0x2e00 kernel/events/core.c:9949
       SyS_perf_event_open+0x39/0x50 kernel/events/core.c:9835
       entry_SYSCALL_64_fastpath+0x29/0xa0

-> #0 (event_mutex){+.+.}:
       lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3914
       __mutex_lock_common kernel/locking/mutex.c:756 [inline]
       __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893
       mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
       perf_trace_destroy+0x28/0x100 kernel/trace/trace_event_perf.c:234
       tp_perf_event_destroy+0x15/0x20 kernel/events/core.c:7943
       _free_event+0x3bd/0x10f0 kernel/events/core.c:4104
       free_event+0x84/0x150 kernel/events/core.c:4128
       perf_event_release_kernel+0x54e/0xc10 kernel/events/core.c:4272
       perf_release+0x37/0x50 kernel/events/core.c:4298
       __fput+0x327/0x7e0 fs/file_table.c:210
       ____fput+0x15/0x20 fs/file_table.c:244
       task_work_run+0x199/0x270 kernel/task_work.c:113
       exit_task_work include/linux/task_work.h:22 [inline]
       do_exit+0x9bb/0x1ad0 kernel/exit.c:865
       do_group_exit+0x149/0x400 kernel/exit.c:968
       get_signal+0x73f/0x16c0 kernel/signal.c:2335
       do_signal+0x90/0x1eb0 arch/x86/kernel/signal.c:809
       exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158
       prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
       syscall_return_slowpath+0x490/0x550 arch/x86/entry/common.c:264
       entry_SYSCALL_64_fastpath+0x9e/0xa0

other info that might help us debug this:

Chain exists of:
  event_mutex --> &cpuctx_mutex --> &event->child_mutex

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&event->child_mutex);
                               lock(&cpuctx_mutex);
                               lock(&event->child_mutex);
  lock(event_mutex);

 *** DEADLOCK ***

2 locks held by syzkaller107260/3655:
 #0:  (&ctx->mutex){+.+.}, at: [<00000000662b4e5e>] perf_event_release_kernel+0x2dc/0xc10 kernel/events/core.c:4259
 #1:  (&event->child_mutex){+.+.}, at: [<00000000501d8b43>] perf_event_release_kernel+0x2ea/0xc10 kernel/events/core.c:4260

stack backtrace:
CPU: 0 PID: 3655 Comm: syzkaller107260 Not tainted 4.15.0-rc8+ #2
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 print_circular_bug.isra.37+0x2cd/0x2dc kernel/locking/lockdep.c:1218
 check_prev_add kernel/locking/lockdep.c:1858 [inline]
 check_prevs_add kernel/locking/lockdep.c:1971 [inline]
 validate_chain kernel/locking/lockdep.c:2412 [inline]
 __lock_acquire+0x30a8/0x3e00 kernel/locking/lockdep.c:3426
 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3914
 __mutex_lock_common kernel/locking/mutex.c:756 [inline]
 __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
 perf_trace_destroy+0x28/0x100 kernel/trace/trace_event_perf.c:234
 tp_perf_event_destroy+0x15/0x20 kernel/events/core.c:7943
 _free_event+0x3bd/0x10f0 kernel/events/core.c:4104
 free_event+0x84/0x150 kernel/events/core.c:4128
 perf_event_release_kernel+0x54e/0xc10 kernel/events/core.c:4272
 perf_release+0x37/0x50 kernel/events/core.c:4298
 __fput+0x327/0x7e0 fs/file_table.c:210
 ____fput+0x15/0x20 fs/file_table.c:244
 task_work_run+0x199/0x270 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x9bb/0x1ad0 kernel/exit.c:865
 do_group_exit+0x149/0x400 kernel/exit.c:968
 get_signal+0x73f/0x16c0 kernel/signal.c:2335
 do_signal+0x90/0x1eb0 arch/x86/kernel/signal.c:809
 exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158
 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
 syscall_return_slowpath+0x490/0x550 arch/x86/entry/common.c:264
 entry_SYSCALL_64

Crashes (2006):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/01/23 19:38 bpf-next 2310035fa03f a5b7566c .config console log report syz C ci-upstream-bpf-next-kasan-gce
2018/01/23 06:17 bpf-next ebdd7b491b8a 228e3d95 .config console log report syz C ci-upstream-bpf-next-kasan-gce
2018/01/22 20:56 bpf-next ebdd7b491b8a 228e3d95 .config console log report syz C ci-upstream-bpf-next-kasan-gce
2017/12/13 08:22 upstream d39a01eff9af ce7f2399 .config console log report syz ci-upstream-kasan-gce
2017/12/13 00:57 upstream a638349bf6c2 414a185f .config console log report syz ci-upstream-kasan-gce-386
2017/12/15 06:58 mmots 82bcf1def3b5 ac20b98c .config console log report syz ci-upstream-mmots-kasan-gce
2017/11/12 11:22 mmots 97530111c84b 00f6ff58 .config console log report syz ci-upstream-mmots-kasan-gce
2017/11/12 11:13 linux-next d9e0e63d9a6f e0a2b195 .config console log report syz skylake-linux-next-kasan-qemu
2017/11/12 11:08 linux-next d9e0e63d9a6f e0a2b195 .config console log report syz ci-upstream-next-kasan-gce
2017/11/10 14:27 linux-next d9e0e63d9a6f e0a2b195 .config console log report syz skylake-linux-next-kasan-qemu
2017/11/10 14:21 linux-next d9e0e63d9a6f e0a2b195 .config console log report syz ci-upstream-next-kasan-gce
2017/11/05 08:13 linux-next 5a3517e009e9 e0a2b195 .config console log report syz ci-upstream-next-kasan-gce
2017/11/05 08:08 linux-next 5a3517e009e9 e0a2b195 .config console log report syz ci-upstream-next-kasan-gce
2017/12/12 08:58 upstream a638349bf6c2 da131727 .config console log report ci-upstream-kasan-gce
2018/01/28 06:15 bpf-next 8223967fe0b8 08146b1a .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 08:39 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 08:38 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 08:35 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 08:34 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 08:30 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 08:23 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 08:20 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 08:18 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 08:17 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 08:16 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 08:00 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:59 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:54 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:41 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:39 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:39 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:37 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:33 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:31 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:30 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:29 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:27 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:25 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:21 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:14 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:10 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:08 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:06 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:02 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 07:02 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 06:54 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 06:53 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 06:50 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 06:46 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 06:27 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 06:07 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 06:04 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
2018/01/27 06:01 bpf-next 8223967fe0b8 1d18b112 .config console log report ci-upstream-bpf-next-kasan-gce
* Struck through repros no longer work on HEAD.