syzbot


INFO: task hung in perf_pending_task_sync

Status: upstream: reported C repro on 2024/08/30 10:20
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+89a27bae950fcb3755f8@syzkaller.appspotmail.com
First crash: 41d, last: 3d11h
Bug presence (2)
Date Name Commit Repro Result
2024/09/14 linux-5.15.y (ToT) 3a5928702e71 C [report] INFO: task hung in perf_pending_task_sync
2024/09/14 upstream (ToT) 0babf683783d C Didn't crash
Fix bisection attempts (1)
Created Duration User Patch Repo Result
2024/09/25 17:37 2h35m fix candidate upstream OK (0) job log

Sample crash report:
INFO: task syz-executor317:5101 blocked for more than 143 seconds.
      Not tainted 5.15.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor317 state:D stack:27168 pid: 5101 ppid:  3581 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 perf_pending_task_sync+0x13c/0x1c0 kernel/events/core.c:5123
 _free_event+0x34/0xe60 kernel/events/core.c:5129
 put_event kernel/events/core.c:5254 [inline]
 perf_event_release_kernel+0x873/0x900 kernel/events/core.c:5379
 perf_release+0x37/0x40 kernel/events/core.c:5389
 __fput+0x3fe/0x8e0 fs/file_table.c:280
 task_work_run+0x129/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fefd2c53af9
RSP: 002b:00007ffee39283e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fefd2c53af9
RDX: 00007fefd2c53af9 RSI: 00000000ffffffff RDI: 0000000000000003
RBP: 000000000002c64e R08: 0000000000000006 R09: 0000000000000006
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffee39283fc
R13: 431bde82d7b634db R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c91fc60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
1 lock held by klogd/3017:
 #0: ffff8880b903a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
2 locks held by getty/3328:
 #0: ffff888029c14098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc9000208e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:108 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:562

Crashes (38):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/29 10:57 linux-5.15.y 3a5928702e71 ba29ff75 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/14 16:44 linux-5.15.y 3a5928702e71 c7e35043 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/10/07 03:53 linux-5.15.y 3a5928702e71 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/10/02 13:41 linux-5.15.y 3a5928702e71 02f9582a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/10/01 16:55 linux-5.15.y 3a5928702e71 ea2b66a6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/10/01 10:04 linux-5.15.y 3a5928702e71 bbd4e0a4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/10/01 04:15 linux-5.15.y 3a5928702e71 bbd4e0a4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/10/01 03:47 linux-5.15.y 3a5928702e71 bbd4e0a4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/10/01 03:39 linux-5.15.y 3a5928702e71 bbd4e0a4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/30 14:25 linux-5.15.y 3a5928702e71 bbd4e0a4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/29 18:49 linux-5.15.y 3a5928702e71 ba29ff75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/27 18:29 linux-5.15.y 3a5928702e71 440b26ec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/27 16:53 linux-5.15.y 3a5928702e71 9314348a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/27 13:11 linux-5.15.y 3a5928702e71 9314348a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/27 12:33 linux-5.15.y 3a5928702e71 9314348a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/26 13:33 linux-5.15.y 3a5928702e71 0d19f247 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/26 13:11 linux-5.15.y 3a5928702e71 0d19f247 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/26 12:42 linux-5.15.y 3a5928702e71 0d19f247 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/25 01:39 linux-5.15.y 3a5928702e71 5643e0e9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/22 18:52 linux-5.15.y 3a5928702e71 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/22 07:00 linux-5.15.y 3a5928702e71 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/22 01:27 linux-5.15.y 3a5928702e71 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/21 11:59 linux-5.15.y 3a5928702e71 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/20 23:34 linux-5.15.y 3a5928702e71 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/20 15:05 linux-5.15.y 3a5928702e71 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/19 15:37 linux-5.15.y 3a5928702e71 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/19 15:25 linux-5.15.y 3a5928702e71 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/16 17:21 linux-5.15.y 3a5928702e71 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/16 14:04 linux-5.15.y 3a5928702e71 08d8a733 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/16 01:16 linux-5.15.y 3a5928702e71 08d8a733 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/15 20:46 linux-5.15.y 3a5928702e71 08d8a733 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/14 10:05 linux-5.15.y 3a5928702e71 c7e35043 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/08 08:27 linux-5.15.y 14e468424d3e 9750182a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/02 11:19 linux-5.15.y fa93fa65db6e 1eda0d14 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/02 08:47 linux-5.15.y fa93fa65db6e 1eda0d14 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/09/01 23:39 linux-5.15.y fa93fa65db6e 1eda0d14 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/08/31 04:02 linux-5.15.y fa93fa65db6e 1eda0d14 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
2024/08/30 10:19 linux-5.15.y fa93fa65db6e ee2602b8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: task hung in perf_pending_task_sync
* Struck through repros no longer work on HEAD.