syzbot

============================================
WARNING: possible recursive locking detected
6.7.0-rc4-syzkaller #0 Not tainted
--------------------------------------------
kworker/u4:8/2472 is trying to acquire lock:
ffff888020c640b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x16e/0x200 fs/hfsplus/bfind.c:33

but task is already holding lock:
ffff888020c640b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x16e/0x200 fs/hfsplus/bfind.c:33

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/u4:8/2472:
 #0: ffff88814424b938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x789/0x15d0 kernel/workqueue.c:2605
 #1: ffffc9000a24fd80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7eb/0x15d0 kernel/workqueue.c:2606
 #2: ffff88806d328848 (&hip->extents_lock){+.+.}-{3:3}, at: hfsplus_ext_write_extent+0x82/0x200 fs/hfsplus/extents.c:149
 #3: ffff888020c640b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x16e/0x200 fs/hfsplus/bfind.c:33
 #4: ffff88806ccdb588 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_extend+0x1c1/0x1090 fs/hfsplus/extents.c:457

stack backtrace:
CPU: 1 PID: 2472 Comm: kworker/u4:8 Not tainted 6.7.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 check_deadlock kernel/locking/lockdep.c:3062 [inline]
 validate_chain kernel/locking/lockdep.c:3856 [inline]
 __lock_acquire+0x20f8/0x3b20 kernel/locking/lockdep.c:5137
 lock_acquire kernel/locking/lockdep.c:5754 [inline]
 lock_acquire+0x1ae/0x520 kernel/locking/lockdep.c:5719
 __mutex_lock_common kernel/locking/mutex.c:603 [inline]
 __mutex_lock+0x175/0x9d0 kernel/locking/mutex.c:747
 hfsplus_find_init+0x16e/0x200 fs/hfsplus/bfind.c:33
 hfsplus_ext_read_extent+0x18f/0x240 fs/hfsplus/extents.c:216
 hfsplus_file_extend+0x695/0x1090 fs/hfsplus/extents.c:461
 hfsplus_bmap_reserve+0x318/0x410 fs/hfsplus/btree.c:358
 __hfsplus_ext_write_extent+0x470/0x5e0 fs/hfsplus/extents.c:104
 hfsplus_ext_write_extent_locked fs/hfsplus/extents.c:139 [inline]
 hfsplus_ext_write_extent_locked fs/hfsplus/extents.c:129 [inline]
 hfsplus_ext_write_extent+0x1c5/0x200 fs/hfsplus/extents.c:150
 hfsplus_write_inode+0x22/0x4f0 fs/hfsplus/super.c:154
 write_inode fs/fs-writeback.c:1473 [inline]
 __writeback_single_inode+0xa91/0xe90 fs/fs-writeback.c:1690
 writeback_sb_inodes+0x599/0x1080 fs/fs-writeback.c:1916
 wb_writeback+0x2a5/0xaa0 fs/fs-writeback.c:2092
 wb_do_writeback fs/fs-writeback.c:2239 [inline]
 wb_workfn+0x29c/0xfe0 fs/fs-writeback.c:2279
 process_one_work+0x886/0x15d0 kernel/workqueue.c:2630
 process_scheduled_works kernel/workqueue.c:2703 [inline]
 worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784
 kthread+0x2c6/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>