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INFO: task hung in perf_event_free_task

Status: upstream: reported C repro on 2019/07/24 19:18
Subsystems: perf
[Documentation on labels]
Reported-by: syzbot+7692cea7450c97fa2a0a@syzkaller.appspotmail.com
First crash: 1530d, last: 14d
Cause bisection: introduced by (bisect log) :
commit 1cf8dfe8a661f0462925df943140e9f6d1ea5233
Author: Peter Zijlstra <peterz@infradead.org>
Date: Sat Jul 13 09:21:25 2019 +0000

  perf/core: Fix race between close() and fork()

Crash: INFO: task hung in perf_event_free_task (log)
Repro: syz .config
  
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
INFO: task hung in perf_event_free_task 3 (6) 2021/04/21 12:35
▶ ▼ Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in perf_event_free_task (3) 3 509d 655d 0/1 auto-obsoleted due to no activity on 2022/08/31 14:29
linux-4.19 INFO: task hung in perf_event_free_task (2) 2 865d 937d 0/1 auto-closed as invalid on 2021/09/09 09:13
linux-4.19 INFO: task hung in perf_event_free_task (4) 4 208d 377d 0/1 upstream: reported on 2022/09/12 12:14
linux-6.1 INFO: task hung in perf_event_free_task origin:upstream C 1 13d 13d 0/3 upstream: reported C repro on 2023/09/12 07:14
linux-4.19 INFO: task hung in perf_event_free_task 5 1080d 1475d 0/1 auto-closed as invalid on 2021/02/06 21:15
upstream INFO: task can't die in perf_event_free_task perf syz unreliable 6 339d 1039d 0/25 auto-obsoleted due to no activity on 2023/04/21 23:56
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2023/09/10 09:52 20m retest repro upstream report log
2023/08/24 03:09 20m retest repro upstream OK log
2023/08/24 03:09 23m retest repro linux-next OK log
2023/07/01 14:14 20m retest repro upstream OK log
2023/07/01 14:14 19m retest repro upstream report log
2023/07/01 14:14 18m retest repro upstream OK log
2023/04/22 13:05 18m retest repro upstream OK log
2023/04/22 13:05 18m retest repro upstream OK log
2023/04/22 13:05 19m retest repro upstream report log
2023/04/22 13:05 21m retest repro upstream OK log
▶ ▼ Fix bisection attempts (2)
Created Duration User Patch Repo Result
2019/12/18 08:58 20m bisect fix upstream error job log (0)
2019/10/12 16:42 33m bisect fix upstream job log (0) log

Sample crash report:
INFO: task syz-executor.0:17871 blocked for more than 143 seconds.
      Not tainted 5.3.0-rc6 #93
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D28696 17871   9205 0x00004006
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x877/0xc50 kernel/sched/core.c:3880
 schedule+0x131/0x1e0 kernel/sched/core.c:3947
 perf_event_free_task+0x54a/0x630 kernel/events/core.c:11606
 copy_process+0x3ad6/0x5ac0 kernel/fork.c:2283
 _do_fork+0x13f/0x5b0 kernel/fork.c:2369
 __do_sys_clone kernel/fork.c:2524 [inline]
 __se_sys_clone kernel/fork.c:2505 [inline]
 __x64_sys_clone+0x1ec/0x230 kernel/fork.c:2505
 do_syscall_64+0xfe/0x140 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459879
Code: Bad RIP value.
RSP: 002b:00007f8dea6c2c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459879
RDX: 9999999999999999 RSI: 0000000000000000 RDI: 0000002102001ffe
RBP: 000000000075bf20 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8dea6c36d4
R13: 00000000004bfd46 R14: 00000000004d1af8 R15: 00000000ffffffff
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 PID: 1057 Comm: khungtaskd Not tainted 5.3.0-rc6 #93
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+0x1d8/0x2f8 lib/dump_stack.c:113
 nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace+0x17/0x20 include/linux/nmi.h:146
 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline]
 watchdog+0xbb9/0xbd0 kernel/hung_task.c:289
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60

Crashes (40):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/08/27 04:11 upstream a55aa89aab90 d21c5d9d .config console log report syz ci-upstream-kasan-gce-smack-root
2021/04/20 09:09 upstream 7af08140979a 4285c989 .config console log report syz C ci-upstream-kasan-gce-smack-root INFO: task hung in perf_event_free_task
2019/08/16 13:14 upstream 329120423947 8fd428a1 .config console log report syz ci-upstream-kasan-gce-smack-root
2019/08/11 10:45 upstream 296d05cb0d3c acb51638 .config console log report syz ci-upstream-kasan-gce-smack-root
2019/08/05 10:56 upstream e21a712a9685 6affd8e8 .config console log report syz ci-upstream-kasan-gce-smack-root
2019/08/05 10:44 upstream e21a712a9685 6affd8e8 .config console log report syz ci-upstream-kasan-gce-root
2019/08/04 04:49 upstream dcb8cfbd8fe9 6affd8e8 .config console log report syz ci-upstream-kasan-gce-root
2019/07/24 13:05 upstream c6dd78fcb8ee 32329ceb .config console log report syz ci-upstream-kasan-gce-smack-root
2019/07/24 13:57 linux-next 9e6dfe8045f8 32329ceb .config console log report syz ci-upstream-linux-next-kasan-gce-root
2022/01/15 01:18 upstream fb3b0673b7d5 53e00b45 .config console log report info ci-upstream-kasan-gce INFO: task hung in perf_event_free_task
2022/01/14 00:46 upstream 455e73a07f6e b8d780ab .config console log report info ci-upstream-kasan-gce INFO: task hung in perf_event_free_task
2022/01/13 10:42 upstream f079ab01b560 44d1319a .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in perf_event_free_task
2022/01/13 06:25 upstream f079ab01b560 44d1319a .config console log report info ci-upstream-kasan-gce INFO: task hung in perf_event_free_task
2021/12/18 21:19 upstream 9eaa88c7036e 44068e19 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: task hung in perf_event_free_task
2021/12/12 05:14 upstream 6f513529296f 49ca1f59 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in perf_event_free_task
2021/11/24 12:45 upstream 5d9f4cf36721 545ab074 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: task hung in perf_event_free_task
2021/09/25 11:44 upstream 7d42e9818258 8cac236e .config console log report info ci-upstream-kasan-gce-root INFO: task hung in perf_event_free_task
2021/09/20 04:58 upstream 20621d2f27a0 70b76c1d .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in perf_event_free_task
2021/07/06 23:27 upstream 3dbdb38e2869 cca78469 .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in perf_event_free_task
2021/05/22 19:15 upstream 23d729263037 3c7fef33 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: task hung in perf_event_free_task
2021/05/17 09:08 upstream d07f6ca923ea a2eb125d .config console log report info ci-upstream-kasan-gce-selinux-root INFO: task hung in perf_event_free_task
2020/09/24 08:37 upstream c9c9e6a49f89 54289b08 .config console log report info ci-upstream-kasan-gce-root
2020/09/07 15:45 upstream a8205e310011 abf9ba4f .config console log report ci-upstream-kasan-gce
2020/02/21 18:25 upstream ca7e1fd1026c bd2a74a3 .config console log report ci-upstream-kasan-gce
2020/02/10 12:23 upstream bb6d3fb354c5 35f5e45e .config console log report ci-upstream-kasan-gce
2020/02/02 16:03 upstream 94f2630b1897 93e5e335 .config console log report ci-upstream-kasan-gce-smack-root
2020/01/19 11:58 upstream 244dc2689085 bc8bc756 .config console log report ci-upstream-kasan-gce
2019/12/31 00:51 upstream fd6988496e79 7f117e28 .config console log report ci-upstream-kasan-gce-selinux-root
2019/10/26 07:28 upstream 8caacaad78b6 413926c5 .config console log report ci-upstream-kasan-gce-selinux-root
2019/08/22 19:07 upstream bb7ba8069de9 d003d6d0 .config console log report ci-upstream-kasan-gce-smack-root
2019/07/17 14:12 upstream 3eb514866f20 0d10349c .config console log report ci-upstream-kasan-gce-selinux-root
2020/05/31 01:34 upstream ffeb595d8481 6f3e1c7c .config console log report ci-upstream-kasan-gce-386
2020/02/27 19:22 upstream f8788d86ab28 59b57593 .config console log report ci-upstream-kasan-gce-386
2019/09/01 23:58 upstream 9f159ae07f07 bad3cce2 .config console log report ci-upstream-kasan-gce-386
2019/07/24 18:32 upstream bed38c3e2dca 32329ceb .config console log report ci-upstream-kasan-gce-386
2019/07/20 07:49 upstream 31cc088a4f5d 1656845f .config console log report ci-upstream-kasan-gce-386
2020/04/13 07:16 linux-next 3b2804993d1e 17a986e5 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/03/06 15:25 linux-next c99b17ac0399 c88c7b75 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/09/12 07:15 linux-next 6d028043b55e f4e53c10 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/08/19 10:51 linux-next da6570438d9b b8ceabfc .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.