INFO: task kworker/u8:2:36 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:2    state:D stack:23552 pid:36    tgid:36    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5349 [inline]
 __schedule+0x1665/0x5590 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7044 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7059
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7116
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
 hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28
 hfsplus_cat_write_inode+0x22b/0x8e0 fs/hfsplus/inode.c:650
 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2118
 process_one_work+0x9a5/0x1760 kernel/workqueue.c:3286
 process_scheduled_works kernel/workqueue.c:3377 [inline]
 worker_thread+0xb49/0x1140 kernel/workqueue.c:3458
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/u8:0/12:
 #0: ffff88801c6d3148
 (
(wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x88b/0x1760 kernel/workqueue.c:3258
 #1: 
ffffc90000117c40
 ((work_completion)(&(&wb->dwork)->work)
){+.+.}-{0:0}
, at: process_one_work+0x8b2/0x1760 kernel/workqueue.c:3259
 #2: 
ffff8880332d20e0
 (
&type->s_umount_key
#55
){.+.+}-{4:4}
, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
 #3: 
ffff8880340840b0
 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28
1 lock held by khungtaskd/31:
 #0: ffffffff8e75f2e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #0: ffffffff8e75f2e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #0: ffffffff8e75f2e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:2/36:
 #0: ffff88801c6d3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x88b/0x1760 kernel/workqueue.c:3258
 #1: ffffc90000ac7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x8b2/0x1760 kernel/workqueue.c:3259
 #2: 
ffff8880260020e0
 (
&type->s_umount_key
#55
){.+.+}-{4:4}
, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
 #3: 
ffff8880297560b0
 (
&tree->tree_lock
){+.+.}-{4:4}
, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28
4 locks held by kworker/u8:3/49:
 #0: ffff88801c6d3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x88b/0x1760 kernel/workqueue.c:3258
 #1: ffffc90000b97c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x8b2/0x1760 kernel/workqueue.c:3259
 #2: ffff88802baae0e0 (&type->s_umount_key#55){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
 #3: ffff88807af6a0b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28
4 locks held by kworker/u8:4/59: