syzbot


INFO: task hung in flush_work

Status: auto-closed as invalid on 2019/10/04 01:39
Reported-by: syzbot+478438c5c9b9ab67ceef@syzkaller.appspotmail.com
First crash: 2106d, last: 1896d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in flush_work v9fs C error 306 2121d 2230d 0/27 auto-obsoleted due to no activity on 2023/04/12 14:31
linux-4.14 INFO: task hung in flush_work C inconclusive 5 1475d 1881d 0/1 upstream: reported C repro on 2019/04/21 07:04
android-49 INFO: task hung in flush_work C 28 2035d 1890d 0/3 public: reported C repro on 2019/04/13 00:00

Sample crash report:
ip6_tunnel: ip6tnl2 xmit: Local address not yet configured!
ip6_tunnel: l0 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl4 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
INFO: task syz-executor.0:18386 blocked for more than 140 seconds.
      Not tainted 4.14.111+ #50
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D28560 18386  22000 0x00000004
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3498
 schedule_timeout+0x736/0xe80 kernel/time/timer.c:1721
 do_wait_for_common kernel/sched/completion.c:91 [inline]
 __wait_for_common kernel/sched/completion.c:112 [inline]
 wait_for_common+0x29c/0x470 kernel/sched/completion.c:123
 flush_work+0x3d2/0x710 kernel/workqueue.c:2908
 lru_add_drain_all_cpuslocked mm/swap.c:722 [inline]
 lru_add_drain_all_cpuslocked+0x2d5/0x420 mm/swap.c:691
 lru_add_drain_all+0xf/0x20 mm/swap.c:730
 SYSC_mlockall mm/mlock.c:802 [inline]
 SyS_mlockall+0x1e1/0x520 mm/mlock.c:790
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
INFO: task syz-executor.0:18445 blocked for more than 140 seconds.
      Not tainted 4.14.111+ #50
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D29776 18445  22000 0x00000004
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3498
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893
 lru_add_drain_all_cpuslocked+0x6c/0x420 mm/swap.c:704
 lru_add_drain_all+0xf/0x20 mm/swap.c:730
 SYSC_mlockall mm/mlock.c:802 [inline]
 SyS_mlockall+0x1e1/0x520 mm/mlock.c:790
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289

Showing all locks held in the system:
1 lock held by khungtaskd/23:
 #0:  (tasklist_lock){.+.?}, at: [<00000000a4358b1a>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4544
2 locks held by getty/1754:
 #0:  (&tty->ldisc_sem){++++}, at: [<00000000a8cb1908>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:275
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<0000000046fe5cbd>] n_tty_read+0x1f7/0x1700 drivers/tty/n_tty.c:2156
2 locks held by syz-executor.0/18386:
 #0:  (cpu_hotplug_lock.rw_sem){++++}, at: [<000000005ec3bce5>] get_online_cpus include/linux/cpu.h:138 [inline]
 #0:  (cpu_hotplug_lock.rw_sem){++++}, at: [<000000005ec3bce5>] lru_add_drain_all+0xa/0x20 mm/swap.c:729
 #1:  (lock#4){+.+.}, at: [<00000000a47b777c>] lru_add_drain_all_cpuslocked+0x6c/0x420 mm/swap.c:704
2 locks held by syz-executor.0/18445:
 #0:  (cpu_hotplug_lock.rw_sem){++++}, at: [<000000005ec3bce5>] get_online_cpus include/linux/cpu.h:138 [inline]
 #0:  (cpu_hotplug_lock.rw_sem){++++}, at: [<000000005ec3bce5>] lru_add_drain_all+0xa/0x20 mm/swap.c:729
 #1:  (lock#4){+.+.}, at: [<00000000a47b777c>] lru_add_drain_all_cpuslocked+0x6c/0x420 mm/swap.c:704

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

NMI backtrace for cpu 0
CPU: 0 PID: 23 Comm: khungtaskd Not tainted 4.14.111+ #50
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x10e lib/dump_stack.c:53
 nmi_cpu_backtrace.cold+0x47/0x86 lib/nmi_backtrace.c:101
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 30697 Comm: kworker/1:5 Not tainted 4.14.111+ #50
Workqueue: events rtc_timer_do_work
task: 00000000549fa857 task.stack: 000000007752bd56
RIP: 0010:queued_spin_lock include/asm-generic/qspinlock.h:88 [inline]
RIP: 0010:do_raw_spin_lock+0xb3/0x1c0 kernel/locking/spinlock_debug.c:113
RSP: 0018:ffff8881a3727b10 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff8881d1842200 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffff88819b90a028 RDI: ffff8881d184273c
RBP: ffff8881d1842738 R08: 000000000000006f R09: 00000000000c03ee
R10: ffff88819b90a028 R11: 0000000000000001 R12: ffff8881d1842748
R13: ffff8881d1842740 R14: ffff8881d1842890 R15: ffffffff88084260
FS:  0000000000000000(0000) GS:ffff8881d7500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000001d9a26001 CR4: 00000000001606a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:117 [inline]
 _raw_spin_lock_irqsave+0x4a/0x60 kernel/locking/spinlock.c:160
 rtc_handle_legacy_irq+0x28/0x180 drivers/rtc/interface.c:513
 rtc_timer_do_work+0x21d/0x610 drivers/rtc/interface.c:881
 process_one_work+0x7c6/0x1510 kernel/workqueue.c:2134
 worker_thread+0x5d7/0x1080 kernel/workqueue.c:2271
 kthread+0x310/0x420 kernel/kthread.c:232
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402
Code: c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e e6 00 00 00 65 8b 05 0e d2 e0 78 39 45 08 74 6a 31 c0 ba 01 00 00 00 f0 0f b1 55 00 <85> c0 75 77 65 8b 1d f2 d1 e0 78 48 b8 00 00 00 00 00 fc ff df 

Crashes (11):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/04/07 01:38 android-4.14 171fc237b3cb c34fde03 .config console log report ci-android-414-kasan-gce-root
2018/12/27 05:11 android-4.14 815e34f802d8 e747ec98 .config console log report ci-android-414-kasan-gce-root
2018/12/12 03:24 android-4.14 e525d2cfbe65 7795ae03 .config console log report ci-android-414-kasan-gce-root
2018/11/08 21:24 android-4.14 6c95b90db52b e85d2a61 .config console log report ci-android-414-kasan-gce-root
2018/09/24 01:35 android-4.14 666c420fa3ea 28d9ac76 .config console log report ci-android-414-kasan-gce-root
2018/09/23 06:21 android-4.14 666c420fa3ea 37079712 .config console log report ci-android-414-kasan-gce-root
2018/09/22 18:11 android-4.14 666c420fa3ea 37079712 .config console log report ci-android-414-kasan-gce-root
2018/09/21 23:01 android-4.14 666c420fa3ea 37079712 .config console log report ci-android-414-kasan-gce-root
2018/09/10 03:25 android-4.14 b859aa7d7a0c 6b5120a4 .config console log report ci-android-414-kasan-gce-root
2018/09/08 21:18 android-4.14 b859aa7d7a0c 6b5120a4 .config console log report ci-android-414-kasan-gce-root
2018/09/08 07:58 android-4.14 b859aa7d7a0c 6b5120a4 .config console log report ci-android-414-kasan-gce-root
* Struck through repros no longer work on HEAD.