syzbot


INFO: task hung in submit_bio_wait

Status: closed as dup on 2017/12/12 16:50
Reported-by: syzbot+00a24be9a2c585a83f9cf76bb3ac135fce12c346@syzkaller.appspotmail.com
First crash: 1887d, last: 1828d
Duplicate of (1):
Title Repro Cause bisect Fix bisect Count Last Reported
INFO: task hung in lo_ioctl 47 1761d 1877d
similar bugs (2):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-44 INFO: task hung in submit_bio_wait 1 1849d 1849d 0/2 auto-closed as invalid on 2019/02/22 12:36
android-49 INFO: task hung in submit_bio_wait 35 1832d 1882d 0/3 auto-closed as invalid on 2019/02/22 14:37

Sample crash report:
INFO: task loop0:10456 blocked for more than 120 seconds.
      Not tainted 4.15.0-rc9+ #284
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
loop0           D24976 10456      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2799 [inline]
 __schedule+0x8eb/0x2060 kernel/sched/core.c:3375
 schedule+0xf5/0x430 kernel/sched/core.c:3434
 schedule_timeout+0x1a3/0x230 kernel/time/timer.c:1769
 io_schedule_timeout+0x26/0x80 kernel/sched/core.c:5030
 do_wait_for_common kernel/sched/completion.c:86 [inline]
 __wait_for_common kernel/sched/completion.c:107 [inline]
 wait_for_common_io kernel/sched/completion.c:124 [inline]
 wait_for_completion_io+0x415/0x770 kernel/sched/completion.c:172
 submit_bio_wait+0x13f/0x1e0 block/bio.c:947
 blkdev_issue_flush+0x226/0x310 block/blk-flush.c:548
 blkdev_fsync+0x86/0xb0 fs/block_dev.c:632
 vfs_fsync_range+0x110/0x260 fs/sync.c:196
 vfs_fsync+0x29/0x30 fs/sync.c:210
 lo_req_flush drivers/block/loop.c:444 [inline]
 do_req_filebacked drivers/block/loop.c:572 [inline]
 loop_handle_cmd drivers/block/loop.c:1724 [inline]
 loop_queue_work+0x12a2/0x3900 drivers/block/loop.c:1738
 kthread_worker_fn+0x32b/0x980 kernel/kthread.c:642
 loop_kthread_worker_fn+0x51/0x60 drivers/block/loop.c:841
 kthread+0x33c/0x400 kernel/kthread.c:238
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:541

Showing all locks held in the system:
2 locks held by khungtaskd/759:
 #0:  (rcu_read_lock){....}, at: [<00000000f6190708>] check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline]
 #0:  (rcu_read_lock){....}, at: [<00000000f6190708>] watchdog+0x1c5/0xd60 kernel/hung_task.c:249
 #1:  (tasklist_lock){.+.+}, at: [<000000006ca9da8f>] debug_show_all_locks+0xd3/0x3d0 kernel/locking/lockdep.c:4465
1 lock held by rsyslogd/3528:
 #0:  (&f->f_pos_lock){+.+.}, at: [<00000000ba6760eb>] __fdget_pos+0x12b/0x190 fs/file.c:770
2 locks held by getty/3650:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000004af9c0b5>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<000000003daeae64>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/3651:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000004af9c0b5>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<000000003daeae64>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/3652:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000004af9c0b5>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<000000003daeae64>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/3653:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000004af9c0b5>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<000000003daeae64>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/3654:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000004af9c0b5>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<000000003daeae64>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/3655:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000004af9c0b5>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<000000003daeae64>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/3656:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000004af9c0b5>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<000000003daeae64>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
1 lock held by syz-executor4/17805:
 #0:  (&lo->lo_ctl_mutex/1){+.+.}, at: [<00000000c31330f7>] lo_ioctl+0x8b/0x1b70 drivers/block/loop.c:1355
1 lock held by syz-executor4/17819:
 #0:  (&lo->lo_ctl_mutex/1){+.+.}, at: [<00000000c31330f7>] lo_ioctl+0x8b/0x1b70 drivers/block/loop.c:1355

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

NMI backtrace for cpu 1
CPU: 1 PID: 759 Comm: khungtaskd Not tainted 4.15.0-rc9+ #284
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
 nmi_cpu_backtrace+0x1d2/0x210 lib/nmi_backtrace.c:103
 nmi_trigger_cpumask_backtrace+0x122/0x180 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline]
 check_hung_task kernel/hung_task.c:132 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline]
 watchdog+0x90c/0xd60 kernel/hung_task.c:249
 kthread+0x33c/0x400 kernel/kthread.c:238
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:541
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54

Crashes (313):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci-upstream-kasan-gce 2018/01/29 08:52 upstream 24b1cccf9229 08d47756 .config console log report
ci-upstream-kasan-gce 2018/01/29 07:10 upstream 24b1cccf9229 08d47756 .config console log report
ci-upstream-kasan-gce 2018/01/29 05:05 upstream 24b1cccf9229 08d47756 .config console log report
ci-upstream-kasan-gce 2018/01/28 15:28 upstream c4e0ca7fa241 08d47756 .config console log report
ci-upstream-kasan-gce 2018/01/26 22:52 upstream 993ca2068b04 1d18b112 .config console log report
ci-upstream-kasan-gce 2018/01/26 21:19 upstream 993ca2068b04 1d18b112 .config console log report
ci-upstream-kasan-gce 2018/01/26 19:07 upstream 993ca2068b04 1d18b112 .config console log report
ci-upstream-kasan-gce 2018/01/26 18:54 upstream 993ca2068b04 1d18b112 .config console log report
ci-upstream-kasan-gce 2018/01/26 17:36 upstream 993ca2068b04 1d18b112 .config console log report
ci-upstream-kasan-gce 2018/01/26 16:18 upstream 993ca2068b04 1d18b112 .config console log report
ci-upstream-kasan-gce 2018/01/26 14:38 upstream 993ca2068b04 1d18b112 .config console log report
ci-upstream-kasan-gce 2018/01/26 09:19 upstream 6e20630e3004 1d18b112 .config console log report
ci-upstream-kasan-gce 2018/01/26 03:54 upstream 6e20630e3004 1d18b112 .config console log report
ci-upstream-kasan-gce 2018/01/26 02:20 upstream 6e20630e3004 1d18b112 .config console log report
ci-upstream-kasan-gce 2018/01/25 16:24 upstream 5b7d27967dab 6b2a715e .config console log report
ci-upstream-kasan-gce 2018/01/25 15:21 upstream 5b7d27967dab 6b2a715e .config console log report
ci-upstream-kasan-gce 2018/01/24 16:02 upstream 1f07476ec143 a5b7566c .config console log report
ci-upstream-kasan-gce 2018/01/23 23:44 upstream 1995266727fa a5b7566c .config console log report
ci-upstream-kasan-gce 2018/01/23 23:05 upstream 1995266727fa a5b7566c .config console log report
ci-upstream-kasan-gce 2018/01/23 00:15 upstream 0d665e7b109d 228e3d95 .config console log report
ci-upstream-kasan-gce 2018/01/22 18:55 upstream 0d665e7b109d 228e3d95 .config console log report
ci-upstream-kasan-gce 2018/01/21 00:35 upstream 24b61240471a fbbdcd92 .config console log report
ci-upstream-kasan-gce 2018/01/20 23:16 upstream 24b61240471a fbbdcd92 .config console log report
ci-upstream-kasan-gce 2018/01/19 19:28 upstream dda3e15231b3 161c1d64 .config console log report
ci-upstream-kasan-gce 2018/01/19 11:00 upstream dda3e15231b3 161c1d64 .config console log report
ci-upstream-kasan-gce 2018/01/18 17:08 upstream 1d966eb4d632 56cc113a .config console log report
ci-upstream-kasan-gce 2018/01/18 00:41 upstream 88dc7fca1800 b8970f31 .config console log report
ci-upstream-kasan-gce 2018/01/18 00:36 upstream 88dc7fca1800 b8970f31 .config console log report
ci-upstream-kasan-gce 2018/01/16 19:23 upstream a8750ddca918 4198e588 .config console log report
ci-upstream-kasan-gce 2018/01/16 16:28 upstream a8750ddca918 4198e588 .config console log report
ci-upstream-kasan-gce 2018/01/16 08:27 upstream a8750ddca918 4198e588 .config console log report
ci-upstream-kasan-gce 2018/01/15 21:53 upstream a8750ddca918 e17f4a5d .config console log report
ci-upstream-kasan-gce 2018/01/15 17:26 upstream a8750ddca918 66d492a6 .config console log report
ci-upstream-kasan-gce 2018/01/15 15:01 upstream a8750ddca918 66d492a6 .config console log report
ci-upstream-kasan-gce 2018/01/15 10:19 upstream a8750ddca918 66d492a6 .config console log report
ci-upstream-kasan-gce 2018/01/14 21:40 upstream 9443c168505d 66d492a6 .config console log report
ci-upstream-kasan-gce 2018/01/13 06:55 upstream c92a9a461dff 9dc808a6 .config console log report
ci-upstream-kasan-gce-386 2018/01/27 05:30 upstream c4e0ca7fa241 1d18b112 .config console log report
ci-upstream-kasan-gce-386 2018/01/26 15:23 upstream 993ca2068b04 1d18b112 .config console log report
ci-upstream-kasan-gce-386 2018/01/25 09:38 upstream 5b7d27967dab 6b2a715e .config console log report
* Struck through repros no longer work on HEAD.