syzbot

INFO: task syz-executor.5:24006 blocked for more than 140 seconds.
      Not tainted 4.14.156-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5  D28160 24006   5848 0x80000002
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3499
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3557
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
 blkdev_put+0x27/0x4c0 fs/block_dev.c:1814
 blkdev_close+0x86/0xb0 fs/block_dev.c:1863
 __fput+0x25e/0x710 fs/file_table.c:210
 task_work_run+0x125/0x1a0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x9cb/0x2a20 kernel/exit.c:875
 do_group_exit+0x100/0x2e0 kernel/exit.c:978
 get_signal+0x39f/0x1cc0 kernel/signal.c:2426
 do_signal+0x96/0x15d0 arch/x86/kernel/signal.c:814
 exit_to_usermode_loop+0x11d/0x160 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x3a3/0x520 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a679
RSP: 002b:00007fafa9adccf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000075c078 RCX: 000000000045a679
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000075c078
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000075c07c
R13: 00007ffff3d81b6f R14: 00007fafa9add9c0 R15: 000000000075c07c
INFO: task syz-executor.1:20072 blocked for more than 140 seconds.
      Not tainted 4.14.156-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D25312 20072      1 0x00000004
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3499
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3557
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
 lo_open+0x19/0xb0 drivers/block/loop.c:1624
 __blkdev_get+0x267/0xf90 fs/block_dev.c:1472
 blkdev_get+0x97/0x8b0 fs/block_dev.c:1612
 blkdev_open+0x1cc/0x250 fs/block_dev.c:1770
 do_dentry_open+0x44e/0xe20 fs/open.c:789
 vfs_open+0x105/0x230 fs/open.c:903
 do_last fs/namei.c:3539 [inline]
 path_openat+0xb6c/0x2be0 fs/namei.c:3681
 do_filp_open+0x1a1/0x280 fs/namei.c:3715
 do_sys_open+0x2ca/0x590 fs/open.c:1096
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4143f0
RSP: 002b:00007fffcaa307b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00000000000da77a RCX: 00000000004143f0
RDX: 00007fffcaa3084a RSI: 0000000000000002 RDI: 00007fffcaa30840
RBP: 00000000000002d5 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffcaa307f0 R14: 00000000000da445 R15: 00007fffcaa30800
INFO: task syz-executor.3:25006 blocked for more than 140 seconds.
      Not tainted 4.14.156-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D25312 25006      1 0x00000004
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3499
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3557
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
 lo_open+0x19/0xb0 drivers/block/loop.c:1624
 __blkdev_get+0x267/0xf90 fs/block_dev.c:1472
 blkdev_get+0x97/0x8b0 fs/block_dev.c:1612
 blkdev_open+0x1cc/0x250 fs/block_dev.c:1770
 do_dentry_open+0x44e/0xe20 fs/open.c:789
 vfs_open+0x105/0x230 fs/open.c:903
 do_last fs/namei.c:3539 [inline]
 path_openat+0xb6c/0x2be0 fs/namei.c:3681
 do_filp_open+0x1a1/0x280 fs/namei.c:3715
 do_sys_open+0x2ca/0x590 fs/open.c:1096
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4143f0
RSP: 002b:00007ffe515403b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00000000000da85e RCX: 00000000004143f0
RDX: 00007ffe5154044a RSI: 0000000000000002 RDI: 00007ffe51540440
RBP: 000000000000017f R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe515403f0 R14: 00000000000da524 R15: 00007ffe51540400
INFO: task syz-executor.2:4399 blocked for more than 140 seconds.
      Not tainted 4.14.156-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D29792  4399   2759 0x00000004
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3499
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3557
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
 loop_control_ioctl+0x183/0x310 drivers/block/loop.c:1997
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0xabe/0x1040 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a679
RSP: 002b:00007f389f994c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a679
RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000007
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f389f9956d4
R13: 00000000004c40dc R14: 00000000004d8b58 R15: 00000000ffffffff
INFO: task syz-executor.2:4403 blocked for more than 140 seconds.
      Not tainted 4.14.156-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D30304  4403   2759 0x00000004
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3499
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3557
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
 loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1983
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0xabe/0x1040 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a679
RSP: 002b:00007f389f973c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a679
RDX: 0000000000000000 RSI: 0000000000004c80 RDI: 0000000000000007
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f389f9746d4
R13: 00000000004c40b1 R14: 00000000004d8b28 R15: 00000000ffffffff
INFO: task syz-executor.2:4406 blocked for more than 140 seconds.
      Not tainted 4.14.156-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D28368  4406   2759 0x00000004
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3499
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3557
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
 loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1983
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0xabe/0x1040 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a679
RSP: 002b:00007f389f952c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 000000000045a679
RDX: 0000000000000000 RSI: 0000000000004c82 RDI: 0000000000000007
RBP: 000000000075c118 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f389f9536d4
R13: 00000000004c40c4 R14: 00000000004d8b40 R15: 00000000ffffffff
INFO: task syz-executor.0:4393 blocked for more than 140 seconds.
      Not tainted 4.14.156-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D28560  4393  27265 0x00000004
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3499
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3557
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
 blkdev_reread_part+0x1b/0x40 block/ioctl.c:192
 loop_reread_partitions+0x7f/0x90 drivers/block/loop.c:614
 loop_set_status+0xbff/0x11f0 drivers/block/loop.c:1183
 loop_set_status64+0xa5/0x100 drivers/block/loop.c:1301
 lo_ioctl+0xd1/0x1a30 drivers/block/loop.c:1431
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x8d0/0x1870 block/ioctl.c:594
 block_ioctl+0xd9/0x120 fs/block_dev.c:1881
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0xabe/0x1040 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a4e7
RSP: 002b:00007f7667c889f8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7667c896d4 RCX: 000000000045a4e7
RDX: 00007f7667c88ab0 RSI: 0000000000004c04 RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000202 R12: 0000000000000004
R13: 0000000000000004 R14: 0000000000000005 R15: 00000000ffffffff
INFO: task syz-executor.5:4401 blocked for more than 140 seconds.
      Not tainted 4.14.156-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5  D28592  4401   5848 0x00000004
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3499
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3557
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
 loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1983
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0xabe/0x1040 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a679
RSP: 002b:00007fafa9afdc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a679
RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000007
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fafa9afe6d4
R13: 00000000004c40dc R14: 00000000004d8b58 R15: 00000000ffffffff
INFO: task syz-executor.5:4404 blocked for more than 140 seconds.
      Not tainted 4.14.156-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5  D28368  4404   5848 0x00000004
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3499
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3557
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
 loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1983
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0xabe/0x1040 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a679
RSP: 002b:00007fafa9adcc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 000000000045a679
RDX: 0000000000000000 RSI: 0000000000004c82 RDI: 0000000000000007
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fafa9add6d4
R13: 00000000004c40c4 R14: 00000000004d8b40 R15: 00000000ffffffff
INFO: task syz-executor.4:4402 blocked for more than 140 seconds.
      Not tainted 4.14.156-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4  D29792  4402  24496 0x00000004
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3499
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3557
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
 loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1983
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0xabe/0x1040 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a679
RSP: 002b:00007f8fe3ae3c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a679
RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000007
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8fe3ae46d4
R13: 00000000004c40dc R14: 00000000004d8b58 R15: 00000000ffffffff

Showing all locks held in the system:
1 lock held by khungtaskd/23:
 #0:  (tasklist_lock){.+.+}, at: [<000000005f844ae6>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4544
1 lock held by rsyslogd/1633:
 #0:  (&f->f_pos_lock){+.+.}, at: [<00000000cf949270>] __fdget_pos+0xb5/0xd0 fs/file.c:769
2 locks held by getty/1761:
 #0:  (&tty->ldisc_sem){++++}, at: [<00000000e5060216>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000f85fc739>] n_tty_read+0x1f7/0x1700 drivers/tty/n_tty.c:2156
1 lock held by syz-executor.5/24006:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<00000000e1167608>] blkdev_put+0x27/0x4c0 fs/block_dev.c:1814
2 locks held by syz-executor.1/20072:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<00000000574caf37>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457
 #1:  (loop_index_mutex){+.+.}, at: [<000000004d1abad8>] lo_open+0x19/0xb0 drivers/block/loop.c:1624
2 locks held by syz-executor.3/25006:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<00000000574caf37>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457
 #1:  (loop_index_mutex){+.+.}, at: [<000000004d1abad8>] lo_open+0x19/0xb0 drivers/block/loop.c:1624
2 locks held by syz-executor.2/4399:
 #0:  (loop_index_mutex){+.+.}, at: [<00000000a38060b1>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1983
 #1:  (&lo->lo_ctl_mutex#2){+.+.}, at: [<000000000af3bd27>] loop_control_ioctl+0x183/0x310 drivers/block/loop.c:1997
1 lock held by syz-executor.2/4403:
 #0:  (loop_index_mutex){+.+.}, at: [<00000000a38060b1>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1983
1 lock held by syz-executor.2/4406:
 #0:  (loop_index_mutex){+.+.}, at: [<00000000a38060b1>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1983
2 locks held by syz-executor.0/4393:
 #0:  (&lo->lo_ctl_mutex/1){+.+.}, at: [<00000000708e35a7>] lo_ioctl+0x86/0x1a30 drivers/block/loop.c:1404
 #1:  (&bdev->bd_mutex){+.+.}, at: [<00000000137c192c>] blkdev_reread_part+0x1b/0x40 block/ioctl.c:192
1 lock held by syz-executor.5/4401:
 #0:  (loop_index_mutex){+.+.}, at: [<00000000a38060b1>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1983
1 lock held by syz-executor.5/4404:
 #0:  (loop_index_mutex){+.+.}, at: [<00000000a38060b1>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1983
1 lock held by syz-executor.4/4402:
 #0:  (loop_index_mutex){+.+.}, at: [<00000000a38060b1>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1983
1 lock held by syz-executor.4/4405:
 #0:  (loop_index_mutex){+.+.}, at: [<00000000a38060b1>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1983
1 lock held by syz-executor.4/4409:
 #0:  (loop_index_mutex){+.+.}, at: [<00000000a38060b1>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1983
2 locks held by blkid/4400:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<00000000574caf37>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457
 #1:  (loop_index_mutex){+.+.}, at: [<000000004d1abad8>] lo_open+0x19/0xb0 drivers/block/loop.c:1624
2 locks held by blkid/4437:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<00000000574caf37>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457
 #1:  (loop_index_mutex){+.+.}, at: [<000000004d1abad8>] lo_open+0x19/0xb0 drivers/block/loop.c:1624

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

NMI backtrace for cpu 0
CPU: 0 PID: 23 Comm: khungtaskd Not tainted 4.14.156-syzkaller #0
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xe5/0x154 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x47/0x86 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x119/0x147 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x629/0xbe0 kernel/hung_task.c:274
 kthread+0x31f/0x430 kernel/kthread.c:232
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 1631 Comm: rs:main Q:Reg Not tainted 4.14.156-syzkaller #0
task: 000000001e007aae task.stack: 00000000a4cd9d3b
RIP: 0010:static_key_false include/linux/jump_label.h:203 [inline]
RIP: 0010:trace_writeback_single_inode include/trace/events/writeback.h:693 [inline]
RIP: 0010:__writeback_single_inode+0x370/0x10a0 fs/fs-writeback.c:1430
RSP: 0018:ffff8881d456f990 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff8881cf78b280 RCX: ffffffff988037fa
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff9aa32f68
RBP: ffff8881d456fa60 R08: 0000000000000001 R09: fffffbfff35465ee
R10: fffffbfff35465ed R11: ffffffff9aa32f6b R12: 0000000000000000
R13: 0000000000000000 R14: ffff8881cf78b2a8 R15: ffff8881cf78b308
FS:  00007f0c1a7da700(0000) GS:ffff8881dbb00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000cb4000 CR3: 00000001d489a002 CR4: 00000000001606a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 writeback_single_inode+0x1ff/0x370 fs/fs-writeback.c:1480
 sync_inode fs/fs-writeback.c:2508 [inline]
 sync_inode_metadata+0xb8/0xf0 fs/fs-writeback.c:2528
 __generic_file_fsync+0x121/0x190 fs/libfs.c:992
 ext4_sync_file+0x3ac/0x1250 fs/ext4/fsync.c:120
 vfs_fsync_range+0x106/0x260 fs/sync.c:196
 generic_write_sync include/linux/fs.h:2713 [inline]
 ext4_file_write_iter+0x883/0xdb0 fs/ext4/file.c:279
 call_write_iter include/linux/fs.h:1798 [inline]
 new_sync_write fs/read_write.c:471 [inline]
 __vfs_write+0x401/0x5a0 fs/read_write.c:484
 vfs_write+0x17f/0x4d0 fs/read_write.c:546
 SYSC_write fs/read_write.c:594 [inline]
 SyS_write+0x102/0x250 fs/read_write.c:586
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7f0c1c23819d
RSP: 002b:00007f0c1a7d8f90 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000400 RCX: 00007f0c1c23819d
RDX: 0000000000000400 RSI: 0000000000c99a90 RDI: 0000000000000005
RBP: 0000000000c99a90 R08: 0000000000c99e80 R09: 00007f0c1bbb57e7
R10: 302038312079614d R11: 0000000000000293 R12: 0000000000000000
R13: 00007f0c1a7d9410 R14: 0000000000cba910 R15: 0000000000c99890
Code: ef d0 ff 8b 44 24 18 85 c0 0f 85 82 00 00 00 e8 b7 ef d0 ff be 04 00 00 00 48 c7 c7 68 2f a3 9a e8 76 9a f3 ff 8b 05 68 f7 22 02 <85> c0 0f 8f 5d 02 00 00 e8 93 ef d0 ff 65 8b 05 1c 49 81 67 89