syzbot

============================================
WARNING: possible recursive locking detected
6.1.30-syzkaller #0 Not tainted
--------------------------------------------
kworker/u4:1/11 is trying to acquire lock:
ffff88807b65c0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x146/0x1c0

but task is already holding lock:
ffff88807b65c0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x146/0x1c0

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/u4:1/11:
 #0: ffff888015686938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x77a/0x11f0
 #1: ffffc90000107d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7bd/0x11f0 kernel/workqueue.c:2264
 #2: ffff88807deea988 (&hip->extents_lock){+.+.}-{3:3}, at: hfsplus_ext_write_extent+0x8a/0x1f0 fs/hfsplus/extents.c:149
 #3: ffff88807b65c0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x146/0x1c0
 #4: ffff88807dee8108 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_extend+0x1d2/0x1b10 fs/hfsplus/extents.c:457

stack backtrace:
CPU: 0 PID: 11 Comm: kworker/u4:1 Not tainted 6.1.30-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_deadlock_bug kernel/locking/lockdep.c:2991 [inline]
 check_deadlock kernel/locking/lockdep.c:3034 [inline]
 validate_chain+0x4726/0x58e0 kernel/locking/lockdep.c:3819
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
 __mutex_lock_common+0x1d4/0x2520 kernel/locking/mutex.c:603
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799
 hfsplus_find_init+0x146/0x1c0
 hfsplus_ext_read_extent fs/hfsplus/extents.c:216 [inline]
 hfsplus_file_extend+0x40a/0x1b10 fs/hfsplus/extents.c:461
 hfsplus_bmap_reserve+0x101/0x4e0 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+0x166/0x1f0 fs/hfsplus/extents.c:150
 hfsplus_write_inode+0x1e/0x5c0 fs/hfsplus/super.c:154
 write_inode fs/fs-writeback.c:1443 [inline]
 __writeback_single_inode+0x67d/0x11e0 fs/fs-writeback.c:1655
 writeback_sb_inodes+0xc21/0x1ac0 fs/fs-writeback.c:1881
 wb_writeback+0x49d/0xe10 fs/fs-writeback.c:2055
 wb_do_writeback fs/fs-writeback.c:2198 [inline]
 wb_workfn+0x427/0x1020 fs/fs-writeback.c:2238
 process_one_work+0x8aa/0x11f0 kernel/workqueue.c:2289
 worker_thread+0xa5f/0x1210 kernel/workqueue.c:2436
 kthread+0x26e/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>