INFO: task syz-executor:5607 blocked in I/O wait for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22152 pid:5607  tgid:5607  ppid:5606   task_flags:0x440100 flags:0x00080800
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5533 [inline]
 __schedule+0x17db/0x58f0 kernel/sched/core.c:7284
 __schedule_loop kernel/sched/core.c:7361 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7376
 io_schedule+0x7f/0xd0 kernel/sched/core.c:8220
 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:258
 __wait_on_bit_lock+0xc9/0x5a0 kernel/sched/wait_bit.c:93
 out_of_line_wait_on_bit_lock+0x13b/0x190 kernel/sched/wait_bit.c:120
 lock_buffer include/linux/buffer_head.h:430 [inline]
 do_get_write_access+0x1bc/0x1070 fs/jbd2/transaction.c:969
 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
 __ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249
 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6514
 __ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6699
 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736
 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2744
 generic_update_time fs/inode.c:2252 [inline]
 file_update_time_flags+0x399/0x440 fs/inode.c:2482
 ext4_page_mkwrite+0x224/0x1140 fs/ext4/inode.c:6902
 do_page_mkwrite+0x147/0x310 mm/memory.c:3816
 wp_page_shared mm/memory.c:4217 [inline]
 do_wp_page+0x1a9c/0x4b80 mm/memory.c:4440
 handle_pte_fault mm/memory.c:6582 [inline]
 __handle_mm_fault mm/memory.c:6707 [inline]
 handle_mm_fault+0x15d7/0x3750 mm/memory.c:6876
 do_user_addr_fault+0xa4f/0x1340 arch/x86/mm/fault.c:1343
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7f4fc8e75b4d
RSP: 002b:00007ffe0d5fe240 EFLAGS: 00010246
RAX: 00007f4fc5c00000 RBX: 00000000000000b0 RCX: 0000000000000000
RDX: 00000000000000b0 RSI: 00007f4fc5ffff50 RDI: 0000000000000003
RBP: 00000000000000b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000000b0
R13: 000055555ec1fea0 R14: 00007ffe0d5fe7d0 R15: 00007f4fc5ffff50
 </TASK>

Showing all locks held in the system:
locks held by kthreadd/2: 1, last CPU#1:
 #0: ffffffff8eeac630 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:198 [inline]
 #0: ffffffff8eeac630 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60 include/linux/srcu.h:305
locks held by kworker/u8:0/12: 6, last CPU#0:
 #0: ffff888020ac8140 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffff888020ac8140 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffff888020ac8140 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #0: ffff888020ac8140 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479