INFO: task kworker/u4:1:144 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:1    state:D
 stack:21080 pid:  144 ppid:     2 flags:0x00004000
Workqueue: writeback wb_workfn
 (flush-7:0)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 hfsplus_find_init+0x150/0x1c0 fs/hfsplus/bfind.c:28
 hfsplus_cat_write_inode+0x21c/0x870 fs/hfsplus/inode.c:613
 write_inode fs/fs-writeback.c:1505 [inline]
 __writeback_single_inode+0x6c3/0xda0 fs/fs-writeback.c:1715
 writeback_sb_inodes+0xa4e/0x1680 fs/fs-writeback.c:1940
 __writeback_inodes_wb+0x12a/0x3f0 fs/fs-writeback.c:2011
 wb_writeback+0x46f/0xbe0 fs/fs-writeback.c:2116
 wb_check_background_flush fs/fs-writeback.c:2182 [inline]
 wb_do_writeback fs/fs-writeback.c:2270 [inline]
 wb_workfn+0xbd6/0xf20 fs/fs-writeback.c:2298
 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/u4:0/9:
 #0: ffff888018fc3938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc90000ce7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffff888024b460e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:418
 #3: ffff888025ab60b0 (&tree->tree_lock){+.+.}-{3:3}, at: hfsplus_find_init+0x150/0x1c0 fs/hfsplus/bfind.c:28
2 locks held by kworker/0:1/13:
1 lock held by khungtaskd/27:
 #0: ffffffff8c31f320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
4 locks held by kworker/u4:1/144:
 #0: ffff888018fc3938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9000173fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffff8880761ee0e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:418
 #3: ffff88807b03a0b0 (&tree->tree_lock){+.+.}-{3:3}, at: hfsplus_find_init+0x150/0x1c0 fs/hfsplus/bfind.c:28
4 locks held by kworker/u4:2/154:
 #0: ffff888018fc3938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc90002057d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffff888059c900e0 (
&type->s_umount_key
#54
){.+.+}-{3:3}
, at: trylock_super+0x1c/0xf0 fs/super.c:418
 #3: 
ffff888059c960b0
 (
&tree->tree_lock
){+.+.}-{3:3}
, at: hfsplus_find_init+0x150/0x1c0 fs/hfsplus/bfind.c:28
4 locks held by kworker/u4:4/1240:
 #0: ffff888018fc3938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: 
ffffc90004d77d00
 (
(work_completion)(&(&wb->dwork)->work)
){+.+.}-{0:0}
, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffff888078e2a0e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:418
 #3: 
ffff888073c180b0 (&tree->tree_lock){+.+.}-{3:3}, at: hfsplus_find_init+0x150/0x1c0 fs/hfsplus/bfind.c:28
2 locks held by getty/3949:
 #0: ffff88814cea6098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: 
ffffc900025e62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
3 locks held by kworker/1:11/4267:
 #0: 
ffff888016c70938
 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9000347fd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: 
ffffffff8d43dbc8
 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74
6 locks held by syz.0.17/5059:
6 locks held by syz.1.18/5074:
4 locks held by kworker/u4:6/5086:
 #0: 
ffff888018fc3938
 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9000304fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffff88801b1ec0e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:418
 #3: 
ffff8880751080b0
 (
&tree->tree_lock
){+.+.}-{3:3}
, at: hfsplus_find_init+0x150/0x1c0 fs/hfsplus/bfind.c:28
6 locks held by syz.2.19/5093:
4 locks held by kworker/u4:7/5109:
 #0: 
ffff888018fc3938
 (
(wq_completion)writeback
){+.+.}-{0:0}
, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9000310fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: 
ffff88802aa380e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:418
 #3: 
ffff8880259fc0b0
 (&tree->tree_lock){+.+.}-{3:3}
, at: hfsplus_find_init+0x150/0x1c0 fs/hfsplus/bfind.c:28
3 locks held by kworker/u4:8/5111:
6 locks held by syz.3.20/5118:
6 locks held by syz.4.21/5143:
3 locks held by kworker/u4:10/5173:
 #0: ffff888016c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9000335fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: 
ffffffff8d43dbc8
 (
rtnl_mutex
){+.+.}-{3:3}
, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
6 locks held by syz.5.22/5175:
2 locks held by syz-executor/5177:
 #0: 
ffffffff8d43dbc8
 (
rtnl_mutex
){+.+.}-{3:3}
, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
, at: rtnetlink_rcv_msg+0x7ee/0xf30 net/core/rtnetlink.c:5684
 #1: 
ffffffff8c323da8
 (