syz-executor1 (10629) used greatest stack depth: 23000 bytes left
INFO: task syz-executor2:10558 blocked for more than 140 seconds.
      Not tainted 4.9.125+ #37
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor2   D25832 10558   7174 0x00000004
 ffff8801bc2297c0 ffff8801b56af900 ffff8801c77cee00 ffff8801d58a0000
 ffff8801db621018 ffff880187377290 ffffffff8277d092 ffff8801bc22a070
 1ffff10030e6ee46 ffffffff83a1ecd0 0000000041b58ab3 ffff8801db6218f0
Call Trace:
 [<ffffffff8277e5bf>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff82788be5>] schedule_timeout+0x735/0xe20 kernel/time/timer.c:1768
 [<ffffffff8277c85a>] io_schedule_timeout+0x1ba/0x390 kernel/sched/core.c:5176
 [<ffffffff815b2094>] io_schedule include/linux/sched.h:460 [inline]
 [<ffffffff815b2094>] dio_await_one fs/direct-io.c:461 [inline]
 [<ffffffff815b2094>] dio_await_completion fs/direct-io.c:515 [inline]
 [<ffffffff815b2094>] do_blockdev_direct_IO fs/direct-io.c:1331 [inline]
 [<ffffffff815b2094>] __blockdev_direct_IO+0x8b54/0xbd10 fs/direct-io.c:1360
 [<ffffffff816b41d8>] ext4_direct_IO_write fs/ext4/inode.c:3507 [inline]
 [<ffffffff816b41d8>] ext4_direct_IO+0x978/0x29c0 fs/ext4/inode.c:3663
 [<ffffffff813fa494>] generic_file_direct_write+0x284/0x510 mm/filemap.c:2655
 [<ffffffff813fa93f>] __generic_file_write_iter+0x21f/0x540 mm/filemap.c:2835
 [<ffffffff8168914d>] ext4_file_write_iter+0x63d/0xd70 fs/ext4/file.c:165
 [<ffffffff814e87a7>] new_sync_write fs/read_write.c:496 [inline]
 [<ffffffff814e87a7>] __vfs_write+0x3d7/0x580 fs/read_write.c:509
 [<ffffffff814eaff7>] vfs_write+0x187/0x520 fs/read_write.c:557
 [<ffffffff814eee29>] SYSC_write fs/read_write.c:604 [inline]
 [<ffffffff814eee29>] SyS_write+0xd9/0x1c0 fs/read_write.c:596
 [<ffffffff8100554f>] do_syscall_64+0x19f/0x480 arch/x86/entry/common.c:282
 [<ffffffff8278c193>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/24:
 #0:  (rcu_read_lock){......}, at: [<ffffffff81309cb0>] rcu_read_unlock include/linux/rcupdate.h:927 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff81309cb0>] rcu_lock_break kernel/hung_task.c:143 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff81309cb0>] check_hung_uninterruptible_tasks kernel/hung_task.c:177 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff81309cb0>] watchdog+0x310/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff813e68fc>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
1 lock held by rsyslogd/2150:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8154c11c>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/2277:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff8278a262>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff81cdd442>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
1 lock held by syz-executor3/25187:
 #0:  (sb_writers#4){.+.+.+}, at: [<ffffffff814ee170>] file_start_write include/linux/fs.h:2640 [inline]
 #0:  (sb_writers#4){.+.+.+}, at: [<ffffffff814ee170>] do_sendfile+0xa80/0xc30 fs/read_write.c:1392
3 locks held by syz-executor2/10558:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8154c11c>] __fdget_pos+0xac/0xd0 fs/file.c:781
 #1:  (sb_writers#4){.+.+.+}, at: [<ffffffff814eb25b>] file_start_write include/linux/fs.h:2640 [inline]
 #1:  (sb_writers#4){.+.+.+}, at: [<ffffffff814eb25b>] vfs_write+0x3eb/0x520 fs/read_write.c:556
 #2:  (&sb->s_type->i_mutex_key#10){++++++}, at: [<ffffffff81688c32>] inode_lock include/linux/fs.h:766 [inline]
 #2:  (&sb->s_type->i_mutex_key#10){++++++}, at: [<ffffffff81688c32>] ext4_file_write_iter+0x122/0xd70 fs/ext4/file.c:100
2 locks held by syz-executor2/10632:
 #0:  (sb_writers#4){.+.+.+}, at: [<ffffffff81553a3f>] sb_start_write include/linux/fs.h:1573 [inline]
 #0:  (sb_writers#4){.+.+.+}, at: [<ffffffff81553a3f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&sb->s_type->i_mutex_key#10){++++++}, at: [<ffffffff814e37d8>] inode_lock include/linux/fs.h:766 [inline]
 #1:  (&sb->s_type->i_mutex_key#10){++++++}, at: [<ffffffff814e37d8>] do_truncate2+0x128/0x1f0 fs/open.c:61
2 locks held by syz-executor2/10633:
 #0:  (sb_writers#4){.+.+.+}, at: [<ffffffff814e174e>] sb_start_write include/linux/fs.h:1573 [inline]
 #0:  (sb_writers#4){.+.+.+}, at: [<ffffffff814e174e>] vfs_fallocate+0x2fe/0x620 fs/open.c:328
 #1:  (&sb->s_type->i_mutex_key#10){++++++}, at: [<ffffffff8175f776>] inode_lock include/linux/fs.h:766 [inline]
 #1:  (&sb->s_type->i_mutex_key#10){++++++}, at: [<ffffffff8175f776>] ext4_fallocate+0x366/0x1e80 fs/ext4/extents.c:4974
1 lock held by syz-executor2/10634:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8154c11c>] __fdget_pos+0xac/0xd0 fs/file.c:781

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

NMI backtrace for cpu 1
CPU: 1 PID: 24 Comm: khungtaskd Not tainted 4.9.125+ #37
 ffff8801d94a7d08 ffffffff81af0ae9 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810967d0 ffff8801d94a7d40
 ffffffff81afb849 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81af0ae9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81af0ae9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81afb849>] nmi_cpu_backtrace.cold.0+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81afb7dc>] nmi_trigger_cpumask_backtrace+0x12c/0x151 lib/nmi_backtrace.c:60
 [<ffffffff810968d4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff8130a04d>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff8130a04d>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff8130a04d>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff8130a04d>] watchdog+0x6ad/0xa20 kernel/hung_task.c:239
 [<ffffffff8113d9ad>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff8278c35c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at pc 0xffffffff8278ada6