syzbot


INFO: task hung in wait_on_page_bit_common

Status: closed as dup on 2017/12/12 16:52
Reported-by: syzbot+ef061880e2ff14267d6cbd3720791ee739c73540@syzkaller.appspotmail.com
First crash: 1887d, last: 1820d
Duplicate of (1):
Title Repro Cause bisect Fix bisect Count Last Reported
INFO: task hung in lo_ioctl 47 1761d 1878d

Sample crash report:
IPVS: ftp: loaded support on port[0] = 21
IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready
INFO: task syz-executor2:15931 blocked for more than 120 seconds.
      Not tainted 4.15.0+ #298
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor2   D21744 15931   4131 0x80000006
Call Trace:
 context_switch kernel/sched/core.c:2845 [inline]
 __schedule+0x8eb/0x2060 kernel/sched/core.c:3421
 schedule+0xf5/0x430 kernel/sched/core.c:3480
 io_schedule+0x1c/0x70 kernel/sched/core.c:5096
 wait_on_page_bit_common+0x4b3/0x770 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+0x282/0x430 mm/filemap.c:533
 filemap_fdatawait_range mm/filemap.c:558 [inline]
 filemap_fdatawait include/linux/fs.h:2590 [inline]
 filemap_write_and_wait+0x7a/0xd0 mm/filemap.c:624
 __sync_blockdev fs/block_dev.c:448 [inline]
 sync_blockdev.part.29+0x50/0x70 fs/block_dev.c:457
 sync_blockdev fs/block_dev.c:444 [inline]
 __blkdev_put+0x18b/0x7f0 fs/block_dev.c:1763
 blkdev_put+0x85/0x4f0 fs/block_dev.c:1835
 blkdev_close+0x8b/0xb0 fs/block_dev.c:1842
 __fput+0x327/0x7e0 fs/file_table.c:209
 ____fput+0x15/0x20 fs/file_table.c:243
 task_work_run+0x199/0x270 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x9bb/0x1ad0 kernel/exit.c:865
 do_group_exit+0x149/0x400 kernel/exit.c:968
 get_signal+0x73a/0x16d0 kernel/signal.c:2469
 do_signal+0x90/0x1e90 arch/x86/kernel/signal.c:809
 exit_to_usermode_loop+0x258/0x2f0 arch/x86/entry/common.c:162
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:265 [inline]
 do_syscall_64+0x6ed/0x940 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x26/0x9b
RIP: 0033:0x453299
RSP: 002b:00007efea734cc58 EFLAGS: 00000212 ORIG_RAX: 0000000000000001
RAX: 0000000000003000 RBX: 000000000071bea0 RCX: 0000000000453299
RDX: 00000000fffffef1 RSI: 0000000020d3f000 RDI: 0000000000000014
RBP: 0000000000000654 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f8880
R13: 00000000ffffffff R14: 00007efea734d6d4 R15: 0000000000000000

Showing all locks held in the system:
2 locks held by khungtaskd/756:
 #0:  (rcu_read_lock){....}, at: [<00000000951271ec>] check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline]
 #0:  (rcu_read_lock){....}, at: [<00000000951271ec>] watchdog+0x1c5/0xd60 kernel/hung_task.c:249
 #1:  (tasklist_lock){.+.+}, at: [<000000008dd44379>] debug_show_all_locks+0xd3/0x3d0 kernel/locking/lockdep.c:4470
1 lock held by rsyslogd/3929:
 #0:  (&f->f_pos_lock){+.+.}, at: [<0000000024acb50a>] __fdget_pos+0x12b/0x190 fs/file.c:765
2 locks held by getty/4050:
 #0:  (&tty->ldisc_sem){++++}, at: [<00000000a60e0f93>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000414844e6>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/4051:
 #0:  (&tty->ldisc_sem){++++}, at: [<00000000a60e0f93>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000414844e6>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/4052:
 #0:  (&tty->ldisc_sem){++++}, at: [<00000000a60e0f93>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000414844e6>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/4053:
 #0:  (&tty->ldisc_sem){++++}, at: [<00000000a60e0f93>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000414844e6>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/4054:
 #0:  (&tty->ldisc_sem){++++}, at: [<00000000a60e0f93>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000414844e6>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/4055:
 #0:  (&tty->ldisc_sem){++++}, at: [<00000000a60e0f93>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000414844e6>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
2 locks held by getty/4056:
 #0:  (&tty->ldisc_sem){++++}, at: [<00000000a60e0f93>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000414844e6>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131
3 locks held by kworker/u4:10/11585:
 #0:  ((wq_completion)"writeback"){+.+.}, at: [<00000000441e169d>] process_one_work+0xaaf/0x1af0 kernel/workqueue.c:2084
 #1:  ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: [<00000000532158a4>] process_one_work+0xb01/0x1af0 kernel/workqueue.c:2088
 #2:  (&type->s_umount_key#27){.+.+}, at: [<00000000395cd791>] trylock_super+0x20/0x100 fs/super.c:395
1 lock held by syz-executor2/15931:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<00000000384bcfab>] __blkdev_put+0xbc/0x7f0 fs/block_dev.c:1757
1 lock held by syz-executor2/16117:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<00000000b5035b8c>] __blkdev_get+0x158/0x10e0 fs/block_dev.c:1439
1 lock held by syz-executor2/16118:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<00000000b5035b8c>] __blkdev_get+0x158/0x10e0 fs/block_dev.c:1439

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

NMI backtrace for cpu 0
CPU: 0 PID: 756 Comm: khungtaskd Not tainted 4.15.0+ #298
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:429
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54

Crashes (800):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci-upstream-kasan-gce 2018/02/06 09:03 upstream 2deb41b24532 a1bc9d40 .config console log report
ci-upstream-kasan-gce 2018/02/05 02:58 upstream 35277995e179 a1bc9d40 .config console log report
ci-upstream-kasan-gce 2018/02/04 23:16 upstream 617aebe6a97e a1bc9d40 .config console log report
ci-upstream-kasan-gce 2018/02/04 17:55 upstream 617aebe6a97e a1bc9d40 .config console log report
ci-upstream-kasan-gce 2018/02/04 17:47 upstream 617aebe6a97e a1bc9d40 .config console log report
ci-upstream-kasan-gce 2018/02/04 17:44 upstream 617aebe6a97e a1bc9d40 .config console log report
ci-upstream-kasan-gce 2018/02/04 15:58 upstream 617aebe6a97e a1bc9d40 .config console log report
ci-upstream-kasan-gce 2018/02/04 08:24 upstream 23c35f48f5fb 632a8c2c .config console log report
ci-upstream-kasan-gce 2018/02/04 07:32 upstream 23c35f48f5fb 632a8c2c .config console log report
ci-upstream-kasan-gce 2018/02/04 05:13 upstream 23c35f48f5fb 632a8c2c .config console log report
ci-upstream-kasan-gce 2018/02/04 03:27 upstream 23c35f48f5fb 632a8c2c .config console log report
ci-upstream-kasan-gce 2018/02/04 02:57 upstream 23c35f48f5fb 632a8c2c .config console log report
ci-upstream-kasan-gce 2018/02/03 22:20 upstream 23c35f48f5fb 632a8c2c .config console log report
ci-upstream-kasan-gce 2018/02/03 18:21 upstream b89e32ccd1be 632a8c2c .config console log report
ci-upstream-kasan-gce 2018/02/03 17:37 upstream b89e32ccd1be 632a8c2c .config console log report
ci-upstream-kasan-gce 2018/02/03 17:22 upstream b89e32ccd1be 632a8c2c .config console log report
ci-upstream-kasan-gce 2018/02/03 15:27 upstream b89e32ccd1be 632a8c2c .config console log report
ci-upstream-kasan-gce 2018/02/03 13:04 upstream b89e32ccd1be 632a8c2c .config console log report
ci-upstream-kasan-gce 2018/02/03 09:36 upstream b89e32ccd1be 632a8c2c .config console log report
ci-upstream-kasan-gce 2018/02/03 08:06 upstream 03f51d4efa22 632a8c2c .config console log report
ci-upstream-kasan-gce 2018/02/02 13:09 upstream 4bf772b14675 826b35d6 .config console log report
ci-upstream-kasan-gce 2018/02/02 06:03 upstream 4bf772b14675 826b35d6 .config console log report
ci-upstream-kasan-gce 2018/02/02 00:20 upstream 7109a04eae81 67bd3383 .config console log report
ci-upstream-kasan-gce 2018/02/01 22:23 upstream 7109a04eae81 67bd3383 .config console log report
ci-upstream-kasan-gce 2018/02/01 02:03 upstream 3da90b159b14 02553e22 .config console log report
ci-upstream-kasan-gce 2018/01/31 19:47 upstream 3da90b159b14 02553e22 .config console log report
ci-upstream-kasan-gce 2018/01/31 14:35 upstream 3da90b159b14 02553e22 .config console log report
ci-upstream-kasan-gce 2018/01/31 06:51 upstream 72906f38934a 02553e22 .config console log report
ci-upstream-kasan-gce 2018/01/31 05:45 upstream 72906f38934a 02553e22 .config console log report
ci-upstream-kasan-gce 2018/01/30 20:02 upstream 6304672b7f0a a899be78 .config console log report
ci-upstream-kasan-gce 2018/01/30 17:23 upstream 6304672b7f0a a899be78 .config console log report
ci-upstream-kasan-gce 2018/01/30 09:23 upstream 6304672b7f0a 08d47756 .config console log report
ci-upstream-kasan-gce 2018/01/30 06:14 upstream 6304672b7f0a 08d47756 .config console log report
ci-upstream-kasan-gce 2018/01/30 02:24 upstream d8a5b80568a9 08d47756 .config console log report
ci-upstream-kasan-gce 2018/01/30 02:20 upstream d8a5b80568a9 08d47756 .config console log report
ci-upstream-kasan-gce 2018/01/30 00:25 upstream d8a5b80568a9 08d47756 .config console log report
ci-upstream-kasan-gce 2018/01/29 18:42 upstream d8a5b80568a9 08d47756 .config console log report
ci-upstream-kasan-gce 2018/01/29 16:35 upstream d8a5b80568a9 08d47756 .config console log report
ci-upstream-kasan-gce 2018/01/29 15:42 upstream d8a5b80568a9 08d47756 .config console log report
ci-upstream-kasan-gce 2018/01/29 15:20 upstream d8a5b80568a9 08d47756 .config console log report
* Struck through repros no longer work on HEAD.