syzbot


INFO: task hung in iterate_bdevs

Status: closed as dup on 2017/12/12 16:45
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+741bd31dd54b3674f877e45d0f160c041a071424@syzkaller.appspotmail.com
First crash: 2547d, last: 2417d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
INFO: task hung in lo_ioctl block 47 2422d 2538d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-49 INFO: task hung in iterate_bdevs 93 2410d 2542d 0/3 auto-closed as invalid on 2019/02/22 12:59
android-44 INFO: task hung in iterate_bdevs 21 2400d 2520d 0/2 auto-closed as invalid on 2019/02/22 13:29

Sample crash report:
jfs: Unrecognized mount option "ìÒ" or missing value
FAT-fs (loop7): Unrecognized mount option "fusectl" or missing value
FAT-fs (loop7): bogus number of reserved sectors
FAT-fs (loop7): Can't find a valid FAT filesystem
Buffer I/O error on dev loop0, logical block 3, async page read
INFO: task syz-executor0:9247 blocked for more than 120 seconds.
      Not tainted 4.16.0+ #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor0   D22952  9247   7865 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2848 [inline]
 __schedule+0x807/0x1e40 kernel/sched/core.c:3490
 schedule+0xef/0x430 kernel/sched/core.c:3549
 io_schedule+0x1c/0x70 kernel/sched/core.c:5169
 wait_on_page_bit_common+0x4dc/0x770 mm/filemap.c:1099
 wait_on_page_bit mm/filemap.c:1132 [inline]
 wait_on_page_writeback include/linux/pagemap.h:546 [inline]
 __filemap_fdatawait_range+0x31e/0x4c0 mm/filemap.c:533
 filemap_fdatawait_keep_errors+0x2d/0xc0 mm/filemap.c:600
 fdatawait_one_bdev+0x50/0x70 fs/sync.c:95
 iterate_bdevs+0x11e/0x291 fs/block_dev.c:2162
 ksys_sync+0x122/0x1d0 fs/sync.c:117
 sys_sync+0xe/0x20 fs/sync.c:124
 do_syscall_64+0x29e/0x9d0 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x455259
RSP: 002b:00007f0156a49c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f0156a4a6d4 RCX: 0000000000455259
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000650 R14: 00000000006fc820 R15: 0000000000000000

Showing all locks held in the system:
3 locks held by kworker/u4:2/48:
 #0: 00000000d7542b93 ((wq_completion)"writeback"){+.+.}, at: __write_once_size include/linux/compiler.h:215 [inline]
 #0: 00000000d7542b93 ((wq_completion)"writeback"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 00000000d7542b93 ((wq_completion)"writeback"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
 #0: 00000000d7542b93 ((wq_completion)"writeback"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:57 [inline]
 #0: 00000000d7542b93 ((wq_completion)"writeback"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline]
 #0: 00000000d7542b93 ((wq_completion)"writeback"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0: 00000000d7542b93 ((wq_completion)"writeback"){+.+.}, at: process_one_work+0xaef/0x1b50 kernel/workqueue.c:2116
 #1: 000000005c922f6e ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0xb46/0x1b50 kernel/workqueue.c:2120
 #2: 000000008723d7e6 (&type->s_umount_key#35){.+.+}, at: trylock_super+0x22/0x110 fs/super.c:395
2 locks held by khungtaskd/881:
 #0: 000000003f57a5a2 (rcu_read_lock){....}, at: check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline]
 #0: 000000003f57a5a2 (rcu_read_lock){....}, at: watchdog+0x1ff/0xf60 kernel/hung_task.c:249
 #1: 000000004ce39f74 (tasklist_lock){.+.+}, at: debug_show_all_locks+0xde/0x34a kernel/locking/lockdep.c:4470
1 lock held by rsyslogd/4354:
 #0: 00000000937b512b (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1a9/0x1e0 fs/file.c:766
2 locks held by getty/4444:
 #0: 00000000510dcd15 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 00000000220dbb04 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4445:
 #0: 00000000d268ce8e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 000000009bf494dd (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4446:
 #0: 00000000d60fe108 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 000000005d5ef72f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4447:
 #0: 00000000966e7855 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 000000009e825239 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4448:
 #0: 00000000e139e61d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 000000005e6eb43f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4449:
 #0: 0000000069693015 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 000000007ee2afdf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4450:
 #0: 000000003b398f6b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 00000000f5c8848a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
1 lock held by blkid/8619:
 #0: 00000000558290de (&bdev->bd_mutex){+.+.}, at: blkdev_put+0x34/0x540 fs/block_dev.c:1808
1 lock held by syz-executor0/9247:
 #0: 00000000558290de (&bdev->bd_mutex){+.+.}, at: iterate_bdevs+0xce/0x291 fs/block_dev.c:2160
1 lock held by syz-executor0/9303:
 #0: 00000000558290de (&bdev->bd_mutex){+.+.}, at: iterate_bdevs+0xce/0x291 fs/block_dev.c:2160

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

NMI backtrace for cpu 1
CPU: 1 PID: 881 Comm: khungtaskd Not tainted 4.16.0+ #4
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+0x1b9/0x294 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103
 nmi_trigger_cpumask_backtrace+0x151/0x192 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+0xc10/0xf60 kernel/hung_task.c:249
 kthread+0x345/0x410 kernel/kthread.c:238
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:411
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 (104):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/04/08 10:42 upstream 3fd14cdcc05a 66f22a7f .config console log report ci-upstream-kasan-gce-root
2018/04/06 02:34 upstream e02d37bf55a9 a932eae6 .config console log report ci-upstream-kasan-gce
2018/04/04 09:09 upstream f2d285669aae 676bd07e .config console log report ci-upstream-kasan-gce
2018/04/04 05:52 upstream f2d285669aae 676bd07e .config console log report ci-upstream-kasan-gce
2018/04/04 02:58 upstream f2d285669aae 676bd07e .config console log report ci-upstream-kasan-gce
2018/04/03 16:43 upstream 642e7fd23353 676bd07e .config console log report ci-upstream-kasan-gce-root
2018/03/31 23:38 upstream 10b84daddbec 0174c6c8 .config console log report ci-upstream-kasan-gce
2018/03/31 05:41 upstream 9dd2326890d8 8fbce0e4 .config console log report ci-upstream-kasan-gce
2018/03/30 13:41 upstream c2a9838452a4 d47f0ed6 .config console log report ci-upstream-kasan-gce
2018/03/30 00:43 upstream 0b412605ef5f d47f0ed6 .config console log report ci-upstream-kasan-gce
2018/03/28 04:53 upstream 3eb2ce825ea1 bf5e585c .config console log report ci-upstream-kasan-gce
2018/03/26 12:35 upstream 3eb2ce825ea1 e033c1f1 .config console log report ci-upstream-kasan-gce
2018/03/26 09:12 upstream 3eb2ce825ea1 e033c1f1 .config console log report ci-upstream-kasan-gce
2018/03/26 02:08 upstream cb6416592bc2 e033c1f1 .config console log report ci-upstream-kasan-gce
2018/03/25 21:21 upstream cb6416592bc2 e033c1f1 .config console log report ci-upstream-kasan-gce
2018/03/25 18:35 upstream cb6416592bc2 e033c1f1 .config console log report ci-upstream-kasan-gce
2018/03/25 03:14 upstream bcfc1f455466 2e9d9054 .config console log report ci-upstream-kasan-gce
2018/03/24 18:16 upstream bcfc1f455466 2e9d9054 .config console log report ci-upstream-kasan-gce
2018/03/24 16:24 upstream 99fec39e7725 2e9d9054 .config console log report ci-upstream-kasan-gce
2018/03/24 10:37 upstream 99fec39e7725 2e9d9054 .config console log report ci-upstream-kasan-gce
2018/03/24 06:25 upstream 99fec39e7725 2e9d9054 .config console log report ci-upstream-kasan-gce
2018/03/23 16:19 upstream f36b7534b833 2e9d9054 .config console log report ci-upstream-kasan-gce
2018/03/21 02:23 upstream 1b5f3ba415fe 113a43ff .config console log report ci-upstream-kasan-gce
2018/03/20 11:52 upstream 1b5f3ba415fe 72c33b66 .config console log report ci-upstream-kasan-gce
2018/03/15 05:26 upstream 3032f8c504d2 08dacaa0 .config console log report ci-upstream-kasan-gce
2018/03/05 11:14 upstream 661e50bc8532 2c6f473e .config console log report ci-upstream-kasan-gce
2018/03/05 06:07 upstream e64b9562ba28 2c6f473e .config console log report ci-upstream-kasan-gce
2018/03/04 04:51 upstream 58bdf601c2de 2c6f473e .config console log report ci-upstream-kasan-gce
2018/02/28 23:17 upstream c02be2334e75 05b5a32c .config console log report ci-upstream-kasan-gce
2018/02/25 19:53 upstream 3664ce2d9309 9fe8aa42 .config console log report ci-upstream-kasan-gce
2018/02/25 19:49 upstream 3664ce2d9309 9fe8aa42 .config console log report ci-upstream-kasan-gce
2018/04/10 01:21 upstream f2d285669aae b9f65507 .config console log report ci-upstream-kasan-gce-386
2018/04/05 22:43 upstream f2d285669aae a932eae6 .config console log report ci-upstream-kasan-gce-386
2018/04/05 13:38 upstream f2d285669aae 5e1ccffc .config console log report ci-upstream-kasan-gce-386
2018/04/05 07:03 upstream f2d285669aae 676bd07e .config console log report ci-upstream-kasan-gce-386
2018/04/05 02:59 upstream f2d285669aae 676bd07e .config console log report ci-upstream-kasan-gce-386
2018/04/04 22:29 upstream f2d285669aae 676bd07e .config console log report ci-upstream-kasan-gce-386
2018/03/28 15:43 upstream 3eb2ce825ea1 bf5e585c .config console log report ci-upstream-kasan-gce-386
2018/03/28 12:58 upstream 3eb2ce825ea1 bf5e585c .config console log report ci-upstream-kasan-gce-386
2018/03/19 11:05 upstream c698ca527893 7e7d7ed2 .config console log report ci-upstream-kasan-gce-386
2018/03/14 22:08 upstream 3032f8c504d2 08dacaa0 .config console log report ci-upstream-kasan-gce-386
2018/02/27 03:25 upstream 4a3928c6f8a5 b370d4a7 .config console log report ci-upstream-kasan-gce-386
2018/01/19 09:37 mmots 216435561218 161c1d64 .config console log report ci-upstream-mmots-kasan-gce
2018/01/13 14:06 linux-next 3e53c7415294 c9e7aeae .config console log report ci-upstream-next-kasan-gce
* Struck through repros no longer work on HEAD.