INFO: task kworker/u4:2:148 blocked for more than 144 seconds.
      Not tainted 5.15.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:2    state:D stack:    0 pid:  148 ppid:     2 flags:0x00000008
Workqueue: writeback wb_workfn (flush-7:4)
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0xf10/0x1e48 kernel/sched/core.c:6373
 schedule+0x11c/0x1c8 kernel/sched/core.c:6456
 rwsem_down_write_slowpath+0xd94/0x17e0 kernel/locking/rwsem.c:1165
 __down_write_common kernel/locking/rwsem.c:1292 [inline]
 __down_write kernel/locking/rwsem.c:1301 [inline]
 down_write+0xe8/0x12c kernel/locking/rwsem.c:1552
 f2fs_balance_fs+0x3e8/0x6a0 fs/f2fs/segment.c:528
 f2fs_write_inode+0x42c/0x4a0 fs/f2fs/inode.c:736
 write_inode fs/fs-writeback.c:1495 [inline]
 __writeback_single_inode+0x584/0x13a4 fs/fs-writeback.c:1705
 writeback_sb_inodes+0x94c/0x1654 fs/fs-writeback.c:1930
 __writeback_inodes_wb+0x110/0x39c fs/fs-writeback.c:2001
 wb_writeback+0x410/0xfc8 fs/fs-writeback.c:2106
 wb_check_background_flush fs/fs-writeback.c:2172 [inline]
 wb_do_writeback fs/fs-writeback.c:2260 [inline]
 wb_workfn+0xc44/0x1070 fs/fs-writeback.c:2288
 process_one_work+0x790/0x11b8 kernel/workqueue.c:2310
 worker_thread+0x910/0x1034 kernel/workqueue.c:2457
 kthread+0x37c/0x45c kernel/kthread.c:334
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870

Showing all locks held in the system:
3 locks held by kworker/1:1/25:
1 lock held by khungtaskd/27:
 #0: ffff800014c917e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311
2 locks held by kworker/u4:1/136:
4 locks held by kworker/u4:2/148:
 #0: ffff0000c0df4938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff80001d787c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff0000d9ce20e0 (&type->s_umount_key#50){++++}-{3:3}, at: trylock_super+0x28/0xf8 fs/super.c:418
 #3: ffff0000c4dad108 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x3e8/0x6a0 fs/f2fs/segment.c:528
1 lock held by udevd/3639:
2 locks held by getty/3784:
 #0: ffff0000d3616098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff80001d60e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158
4 locks held by kworker/u4:9/4149:
 #0: ffff0000c03f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff800020367c00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff800016be7090 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf4/0x9bc net/core/net_namespace.c:561
 #3: ffff0000e3f693e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_destruct+0x11c/0x2dc drivers/net/wireguard/device.c:233
2 locks held by kworker/u4:10/4178:
7 locks held by syz.4.62/4366:
2 locks held by kworker/0:7/5780:
 #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff800020047c00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
1 lock held by syz.0.581/6231:
 #0: ffff0000c815e898 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
 #0: ffff0000c815e898 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x15c/0x2b4 mm/util.c:549
2 locks held by syz.0.581/6232:

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