loop0: detected capacity change from 0 to 1024
============================================
WARNING: possible recursive locking detected
6.15.0-rc1-syzkaller-00333-g5aaaedb0cb54 #0 Not tainted
--------------------------------------------
syz.0.0/5322 is trying to acquire lock:
ffff88803eeac108 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x21d/0x1b70 fs/hfsplus/extents.c:458

but task is already holding lock:
ffff88803eeae988 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x21d/0x1b70 fs/hfsplus/extents.c:458

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

       CPU0
       ----
  lock(&HFSPLUS_I(inode)->extents_lock);
  lock(&HFSPLUS_I(inode)->extents_lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

3 locks held by syz.0.0/5322:
 #0: ffff88803eeaeb78 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
 #0: ffff88803eeaeb78 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: generic_file_write_iter+0xe2/0x5e0 mm/filemap.c:4242
 #1: ffff88803eeae988 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x21d/0x1b70 fs/hfsplus/extents.c:458
 #2: ffff8880443020b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfsplus_find_init+0x14f/0x1d0 fs/hfsplus/bfind.c:28

stack backtrace:
CPU: 0 UID: 0 PID: 5322 Comm: syz.0.0 Not tainted 6.15.0-rc1-syzkaller-00333-g5aaaedb0cb54 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_deadlock_bug+0x2be/0x2d0 kernel/locking/lockdep.c:3042
 check_deadlock kernel/locking/lockdep.c:3094 [inline]
 validate_chain+0x928/0x24e0 kernel/locking/lockdep.c:3896
 __lock_acquire+0xad5/0xd80 kernel/locking/lockdep.c:5235
 lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866
 __mutex_lock_common kernel/locking/mutex.c:601 [inline]
 __mutex_lock+0x1a5/0x10c0 kernel/locking/mutex.c:746
 hfsplus_file_extend+0x21d/0x1b70 fs/hfsplus/extents.c:458
 hfsplus_bmap_reserve+0x105/0x4e0 fs/hfsplus/btree.c:358
 __hfsplus_ext_write_extent+0x2a4/0x5c0 fs/hfsplus/extents.c:104
 __hfsplus_ext_cache_extent+0x84/0xe10 fs/hfsplus/extents.c:186
 hfsplus_ext_read_extent fs/hfsplus/extents.c:218 [inline]
 hfsplus_file_extend+0x48e/0x1b70 fs/hfsplus/extents.c:462
 hfsplus_get_block+0x408/0x14f0 fs/hfsplus/extents.c:245
 __block_write_begin_int+0x691/0x1930 fs/buffer.c:2116
 block_write_begin fs/buffer.c:2227 [inline]
 cont_write_begin+0x781/0xb40 fs/buffer.c:2566
 hfsplus_write_begin+0x68/0xb0 fs/hfsplus/inode.c:46
 generic_perform_write+0x329/0xa10 mm/filemap.c:4102
 generic_file_write_iter+0x10e/0x5e0 mm/filemap.c:4245
 aio_write+0x56d/0x7d0 fs/aio.c:1633
 __io_submit_one fs/aio.c:-1 [inline]
 io_submit_one+0x8a9/0x18b0 fs/aio.c:2052
 __do_sys_io_submit fs/aio.c:2111 [inline]
 __se_sys_io_submit+0x17a/0x2e0 fs/aio.c:2081
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f39d4b8d169
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f39d5aae038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1
RAX: ffffffffffffffda RBX: 00007f39d4da5fa0 RCX: 00007f39d4b8d169
RDX: 0000200000000540 RSI: 000000000000003b RDI: 00007f39d5a64000
RBP: 00007f39d4c0e990 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f39d4da5fa0 R15: 00007ffce2070848
 </TASK>