INFO: task syz.1.455:5193 blocked for more than 421 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.455       state:D stack:0     pid:5193  tgid:5193  ppid:3239   task_flags:0x440040 flags:0x00000002
Call Trace:
[<ffffffff8666de56>] context_switch kernel/sched/core.c:5256 [inline]
[<ffffffff8666de56>] __schedule+0x102c/0x451e kernel/sched/core.c:6863
[<ffffffff8667140c>] __schedule_loop kernel/sched/core.c:6945 [inline]
[<ffffffff8667140c>] schedule+0xc4/0x35e kernel/sched/core.c:6960
[<ffffffff8667182a>] io_schedule+0x78/0xd4 kernel/sched/core.c:7789
[<ffffffff86672898>] bit_wait_io+0x12/0xa2 kernel/sched/wait_bit.c:250
[<ffffffff866726bc>] __wait_on_bit_lock+0x12c/0x204 kernel/sched/wait_bit.c:93
[<ffffffff86672862>] out_of_line_wait_on_bit_lock+0xce/0xf2 kernel/sched/wait_bit.c:120
[<ffffffff80db0c18>] wait_on_bit_lock_io include/linux/wait_bit.h:221 [inline]
[<ffffffff80db0c18>] __lock_buffer+0x6a/0x7e fs/buffer.c:71
[<ffffffff811aac96>] lock_buffer include/linux/buffer_head.h:432 [inline]
[<ffffffff811aac96>] do_get_write_access+0x848/0x136a fs/jbd2/transaction.c:968
[<ffffffff811ab97e>] jbd2_journal_get_write_access+0x1c6/0x234 fs/jbd2/transaction.c:1242
[<ffffffff80ffbdaa>] __ext4_journal_get_write_access+0x68/0x316 fs/ext4/ext4_jbd2.c:241
[<ffffffff8107414e>] ext4_reserve_inode_write+0x124/0x266 fs/ext4/inode.c:6290
[<ffffffff810749c0>] __ext4_mark_inode_dirty+0x1c6/0x90c fs/ext4/inode.c:6465
[<ffffffff81084998>] ext4_dirty_inode+0xb6/0x10c fs/ext4/inode.c:6502