INFO: task kworker/u8:4:130 blocked for more than 163 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:4    state:D stack:0     pid:130   tgid:130   ppid:2      task_flags:0x4208060 flags:0x00000010
Workqueue: writeback wb_workfn (flush-7:0)
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:742 (T)
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1250/0x2a7c kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:6960
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7017
 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:2313 [inline]
 f2fs_balance_fs+0x4c0/0x6d8 fs/f2fs/segment.c:464
 __writeback_inodes_wb+0xec/0x228 fs/fs-writeback.c:2107
      Not tainted syzkaller #0
Call trace:
 write_inode fs/fs-writeback.c:1582 [inline]
 __writeback_single_inode+0x6b0/0x16b8 fs/fs-writeback.c:1802
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844
      Not tainted syzkaller #0
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1250/0x2a7c kernel/sched/core.c:6863
 f2fs_down_write fs/f2fs/f2fs.h:2313 [inline]
 f2fs_balance_fs+0x4c0/0x6d8 fs/f2fs/segment.c:464
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x958/0xed8 kernel/workqueue.c:3421
 #2: ffff0000e1f5a0e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563
 #1: ffff800099ef7be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #1: ffff8000a1267be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #1: ffff8000a33a7be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #1: ffff8000a4287be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff0000d5a220e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563
 #2: ffff0000d3dd60e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563
1 lock held by syslogd/6196:
3 locks held by syz.0.17/6765:
 #1: ffff80009d4d7be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
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