INFO: task kworker/u8:5:779 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:5    state:D stack:0     pid:779   tgid:779   ppid:2      task_flags:0x4208060 flags:0x00000010
Workqueue: writeback wb_workfn (flush-7:2)
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:741 (T)
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x13b0/0x2864 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:7026
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7083
 rwsem_down_write_slowpath+0x6b4/0x10f4 kernel/locking/rwsem.c:1185
 __down_write_common kernel/locking/rwsem.c:1317 [inline]
 __down_write kernel/locking/rwsem.c:1326 [inline]
 down_write+0xb4/0xc0 kernel/locking/rwsem.c:1591
 f2fs_down_write fs/f2fs/f2fs.h:2294 [inline]
 f2fs_balance_fs+0x4b8/0x6ec fs/f2fs/segment.c:464
 f2fs_write_inode+0x3a8/0x684 fs/f2fs/inode.c:820
 write_inode fs/fs-writeback.c:1564 [inline]
 __writeback_single_inode+0x5ac/0x13e8 fs/fs-writeback.c:1784
 writeback_sb_inodes+0x55c/0xe40 fs/fs-writeback.c:2015
 __writeback_inodes_wb+0xec/0x228 fs/fs-writeback.c:2086
 wb_writeback+0x3e0/0xd70 fs/fs-writeback.c:2197
 wb_check_old_data_flush fs/fs-writeback.c:2301 [inline]
 wb_do_writeback fs/fs-writeback.c:2354 [inline]
 wb_workfn+0xa08/0xdc0 fs/fs-writeback.c:2382
 process_one_work+0x7e8/0x155c kernel/workqueue.c:3263
 process_scheduled_works kernel/workqueue.c:3346 [inline]
 worker_thread+0x958/0xed8 kernel/workqueue.c:3427
 kthread+0x5fc/0x75c kernel/kthread.c:463
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844

Showing all locks held in the system:
1 lock held by khungtaskd/32:
 #0: ffff80008f76b560 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330
4 locks held by kworker/u8:5/779:
 #0: ffff0000c1f7b148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3237
 #1: ffff80009d8b7be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3237
 #2: ffff0000d8d660e0 (&type->s_umount_key#55){++++}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:562
 #3: ffff0000c5b7d478 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2294 [inline]
 #3: ffff0000c5b7d478 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x4b8/0x6ec fs/f2fs/segment.c:464
1 lock held by klogd/6181:
2 locks held by getty/6333:
 #0: ffff0000cd1dd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80009bb2b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfa4 drivers/tty/n_tty.c:2222
5 locks held by syz.2.104/7220:

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