INFO: task syz-executor0:8713 blocked for more than 120 seconds.
      Not tainted 4.9.69-g3f1d77c #108
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor0   D26288  8713   3579 0x00000004
 ffff8801d1c86000 ffff8801ccf8aa00 ffff8801c48dda40 ffff8801d1c83000
 ffff8801db221418 ffff8801c6617400 ffffffff8389932b ffffffff81239480
 ffff8801c66174b8 00ffffff81d29572 ffff8801db221ce8 ffff8801db221d10
Call Trace:
 [<ffffffff8389a8cf>] schedule+0x7f/0x1b0 kernel/sched/core.c:3550
 [<ffffffff838a6b03>] schedule_timeout+0x643/0x1220 kernel/time/timer.c:1770
 [<ffffffff83898ade>] io_schedule_timeout+0x1be/0x390 kernel/sched/core.c:5172
 [<ffffffff8389c23e>] do_wait_for_common kernel/sched/completion.c:75 [inline]
 [<ffffffff8389c23e>] __wait_for_common kernel/sched/completion.c:93 [inline]
 [<ffffffff8389c23e>] wait_for_common_io kernel/sched/completion.c:107 [inline]
 [<ffffffff8389c23e>] wait_for_completion_io+0x20e/0x2e0 kernel/sched/completion.c:155
 [<ffffffff81cd719b>] submit_bio_wait+0x11b/0x180 block/bio.c:885
 [<ffffffff81d0a527>] blkdev_issue_flush+0x157/0x220 block/blk-flush.c:518
 [<ffffffff816267e5>] blkdev_fsync+0x85/0xb0 fs/block_dev.c:378
 [<ffffffff8161214a>] vfs_fsync_range+0x10a/0x250 fs/sync.c:195
 [<ffffffff81629396>] generic_write_sync include/linux/fs.h:2586 [inline]
 [<ffffffff81629396>] blkdev_write_iter+0x2a6/0x380 fs/block_dev.c:1720
 [<ffffffff8156a140>] vfs_iter_write+0x2e0/0x450 fs/read_write.c:393
 [<ffffffff8160f0c5>] iter_file_splice_write+0x5b5/0xb60 fs/splice.c:768
 [<ffffffff81609f05>] do_splice_from fs/splice.c:870 [inline]
 [<ffffffff81609f05>] direct_splice_actor+0x125/0x180 fs/splice.c:1037
 [<ffffffff8160b4cc>] splice_direct_to_actor+0x2cc/0x800 fs/splice.c:992
 [<ffffffff8160bba7>] do_splice_direct+0x1a7/0x270 fs/splice.c:1080
 [<ffffffff8156eddb>] do_sendfile+0x54b/0xd30 fs/read_write.c:1401
 [<ffffffff81570d31>] SYSC_sendfile64 fs/read_write.c:1456 [inline]
 [<ffffffff81570d31>] SyS_sendfile64+0xd1/0x160 fs/read_write.c:1448
 [<ffffffff838aab05>] entry_SYSCALL_64_fastpath+0x23/0xc6

Showing all locks held in the system:
3 locks held by kworker/u4:2/45:
 #0:  ("writeback"){++++.+}, at: [<ffffffff81187729>] __write_once_size include/linux/compiler.h:272 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff81187729>] atomic64_set arch/x86/include/asm/atomic64_64.h:33 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff81187729>] atomic_long_set include/asm-generic/atomic-long.h:56 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff81187729>] set_work_data kernel/workqueue.c:616 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff81187729>] set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff81187729>] process_one_work+0x6a9/0x15f0 kernel/workqueue.c:2084
 #1:  ((&(&wb->dwork)->work)){+.+.+.}, at: [<ffffffff8118775b>] process_one_work+0x6db/0x15f0 kernel/workqueue.c:2088
 #2:  (&type->s_umount_key#22){.+.+..}, at: [<ffffffff81575e50>] trylock_super+0x20/0x100 fs/super.c:393
2 locks held by khungtaskd/514:
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136fe15>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136fe15>] watchdog+0x125/0xa70 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.?..}, at: [<ffffffff812355e0>] debug_show_all_locks+0x70/0x280 kernel/locking/lockdep.c:4336
1 lock held by rsyslogd/3166:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815cfb1f>] __fdget_pos+0x9f/0xc0 fs/file.c:781
2 locks held by getty/3297:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff838a8cf2>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff82002084>] n_tty_read+0x1f4/0x16c0 drivers/tty/n_tty.c:2133

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

NMI backtrace for cpu 1
CPU: 1 PID: 514 Comm: khungtaskd Not tainted 4.9.69-g3f1d77c #108
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d9b57d00 ffffffff81d90a29 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810ba1a0 ffff8801d9b57d38
 ffffffff81d9bb4d 0000000000000001 0000000000000000 ffff8801ce41cc18
Call Trace:
 [<ffffffff81d90a29>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d90a29>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81d9bb4d>] nmi_cpu_backtrace+0xfd/0x120 lib/nmi_backtrace.c:99
 [<ffffffff81d9bc87>] nmi_trigger_cpumask_backtrace+0x117/0x190 lib/nmi_backtrace.c:60
 [<ffffffff810ba294>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff813703e0>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff813703e0>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff813703e0>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff813703e0>] watchdog+0x6f0/0xa70 kernel/hung_task.c:239
 [<ffffffff811985ed>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff838aadaa>] ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:433
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at pc 0xffffffff838a9766