hfsplus: b-tree write err: -5, ino 8
============================================
WARNING: possible recursive locking detected
6.3.0-rc4-syzkaller-00199-g7b50567bdcad #0 Not tainted
--------------------------------------------
kworker/u4:0/9 is trying to acquire lock:
ffff88801ca900b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x14a/0x1c0

but task is already holding lock:
ffff88801ca900b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x14a/0x1c0

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&tree->tree_lock/1);
  lock(&tree->tree_lock/1);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

5 locks held by kworker/u4:0/9:
 #0: ffff888017513138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x77e/0x10e0 kernel/workqueue.c:2363
 #1: ffffc900000e7d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7c8/0x10e0 kernel/workqueue.c:2365
 #2: ffff8880774fa988 (&hip->extents_lock){+.+.}-{3:3}, at: hfsplus_ext_write_extent+0x8e/0x1f0 fs/hfsplus/extents.c:149
 #3: ffff88801ca900b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x14a/0x1c0
 #4: ffff8880774f8108 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_extend+0x1d6/0x1b10 fs/hfsplus/extents.c:457

stack backtrace:
CPU: 0 PID: 9 Comm: kworker/u4:0 Not tainted 6.3.0-rc4-syzkaller-00199-g7b50567bdcad #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_deadlock_bug kernel/locking/lockdep.c:2991 [inline]
 check_deadlock kernel/locking/lockdep.c:3034 [inline]
 validate_chain+0x472a/0x58e0 kernel/locking/lockdep.c:3819
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056
 lock_acquire+0x1e1/0x520 kernel/locking/lockdep.c:5669
 __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799
 hfsplus_find_init+0x14a/0x1c0
 hfsplus_ext_read_extent fs/hfsplus/extents.c:216 [inline]
 hfsplus_file_extend+0x40e/0x1b10 fs/hfsplus/extents.c:461
 hfsplus_bmap_reserve+0x105/0x4e0 fs/hfsplus/btree.c:358
 __hfsplus_ext_write_extent+0x2a4/0x5b0 fs/hfsplus/extents.c:104
 hfsplus_ext_write_extent_locked fs/hfsplus/extents.c:139 [inline]
 hfsplus_ext_write_extent+0x16a/0x1f0 fs/hfsplus/extents.c:150
 hfsplus_write_inode+0x22/0x5e0 fs/hfsplus/super.c:154
 write_inode fs/fs-writeback.c:1453 [inline]
 __writeback_single_inode+0x69b/0xfb0 fs/fs-writeback.c:1665
 writeback_sb_inodes+0x8ef/0x11d0 fs/fs-writeback.c:1891
 wb_writeback+0x458/0xc70 fs/fs-writeback.c:2065
 wb_do_writeback fs/fs-writeback.c:2208 [inline]
 wb_workfn+0x400/0xff0 fs/fs-writeback.c:2248
 process_one_work+0x8a0/0x10e0 kernel/workqueue.c:2390
 worker_thread+0xa63/0x1210 kernel/workqueue.c:2537
 kthread+0x270/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>