syzbot


INFO: task hung in perf_event_free_task (2)

Status: auto-closed as invalid on 2021/09/09 09:13
Reported-by: syzbot+29ae4b95ec808a996a5c@syzkaller.appspotmail.com
First crash: 701d, last: 629d
similar bugs (5):
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 273d 419d 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 (4) 3 43d 141d 0/1 upstream: reported on 2022/09/12 12:14
upstream INFO: task hung in perf_event_free_task C done error 40 19d 1286d 0/24 upstream: reported C repro on 2019/07/24 19:18
linux-4.19 INFO: task hung in perf_event_free_task 5 843d 1239d 0/1 auto-closed as invalid on 2021/02/06 21:15
upstream INFO: task can't die in perf_event_free_task syz unreliable 6 103d 803d 0/24 upstream: reported syz repro on 2020/11/19 15:42

Sample crash report:
ieee802154 phy1 wpan1: encryption failed: -22
ieee802154 phy0 wpan0: encryption failed: -22
ieee802154 phy1 wpan1: encryption failed: -22
ieee802154 phy0 wpan0: encryption failed: -22
ieee802154 phy1 wpan1: encryption failed: -22
INFO: task syz-executor.1:1379 blocked for more than 140 seconds.
      Not tainted 4.19.190-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D27512  1379   8123 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 perf_event_free_task+0x4cf/0x660 kernel/events/core.c:11348
 copy_process.part.0+0x3710/0x8260 kernel/fork.c:2136
 copy_process kernel/fork.c:1709 [inline]
 _do_fork+0x22f/0xf30 kernel/fork.c:2218
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4665f9
Code: Bad RIP value.
RSP: 002b:00007f61edbdc188 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9
RDX: 9999999999999999 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00000000004bfce1 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffc4dbb543f R14: 00007f61edbdc300 R15: 0000000000022000

Showing all locks held in the system:
1 lock held by khungtaskd/1569:
 #0: 000000001080dc30 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441
no locks held by in:imklog/7806.
2 locks held by agetty/8028:
 #0: 00000000362e28eb (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
 #1: 00000000d2459445 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1950 drivers/tty/n_tty.c:2154
3 locks held by kworker/u4:6/9499:
 #0: 00000000cc852d40 (&rq->lock){-.-.}, at: idle_balance kernel/sched/fair.c:9701 [inline]
 #0: 00000000cc852d40 (&rq->lock){-.-.}, at: pick_next_task_fair+0x556/0x1570 kernel/sched/fair.c:6840
 #1: 000000001080dc30 (rcu_read_lock){....}, at: cpu_of kernel/sched/sched.h:921 [inline]
 #1: 000000001080dc30 (rcu_read_lock){....}, at: __update_idle_core+0x39/0x3e0 kernel/sched/fair.c:6057
 #2: 00000000f3003770 (&base->lock){-.-.}, at: lock_timer_base+0x55/0x1b0 kernel/time/timer.c:950

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

NMI backtrace for cpu 1
CPU: 1 PID: 1569 Comm: khungtaskd Not tainted 4.19.190-syzkaller #0
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+0x1fc/0x2ef lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline]
 watchdog+0x991/0xe60 kernel/hung_task.c:287
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3481 Comm: kworker/0:2 Not tainted 4.19.190-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events defense_work_handler
RIP: 0010:nr_blockdev_pages+0x77/0x100 fs/block_dev.c:932
Code: 03 80 3c 28 00 0f 85 86 00 00 00 4c 8b 63 08 49 8d 7c 24 30 48 89 f8 48 c1 e8 03 80 3c 28 00 0f 85 84 00 00 00 4d 8b 64 24 30 <49> 8d bc 24 e8 00 00 00 48 89 f8 48 c1 e8 03 80 3c 28 00 75 63 48
RSP: 0018:ffff8880a9e27bb0 EFLAGS: 00000246
RAX: 1ffff11011f672a1 RBX: ffff88808fb39340 RCX: ffffffff814bbe1b
RDX: 0000000000000000 RSI: ffffffff81b1cd93 RDI: ffff88808fb39508
RBP: dffffc0000000000 R08: 0000000000000001 R09: fffffbfff13c24e8
R10: ffffffff89e12743 R11: 0000000000000000 R12: ffff88808fb396e0
R13: 0000000000000000 R14: ffff8880ba02a840 R15: ffff8880ba02f000
FS:  0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f451bfb8010 CR3: 00000000a1d0c000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 si_meminfo+0x104/0x220 mm/page_alloc.c:4785
 update_defense_level+0x7f/0x10f0 net/netfilter/ipvs/ip_vs_ctl.c:106
 defense_work_handler+0x25/0xe0 net/netfilter/ipvs/ip_vs_ctl.c:229
 process_one_work+0x864/0x1570 kernel/workqueue.c:2152
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2295
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

Crashes (2):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci2-linux-4-19 2021/05/12 09:12 linux-4.19.y 3c8c23092588 86294427 .config console log report info INFO: task hung in perf_event_free_task
ci2-linux-4-19 2021/03/01 08:21 linux-4.19.y 2d19be4653f5 4c37c133 .config console log report info INFO: task hung in perf_event_free_task
* Struck through repros no longer work on HEAD.