loop3: detected capacity change from 0 to 1024
============================================
WARNING: possible recursive locking detected
6.16.0-next-20250808-syzkaller #0 Not tainted
--------------------------------------------
syz.3.94/6377 is trying to acquire lock:
ffff888053d79548 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_get_block+0x39e/0x1530 fs/hfsplus/extents.c:260

but task is already holding lock:
ffff888053d787c8 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1fc/0x1990 fs/hfsplus/extents.c:455

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

5 locks held by syz.3.94/6377:
 #0: ffff888029d420e0 (&type->s_umount_key#64/1){+.+.}-{4:4}, at: alloc_super+0x204/0x970 fs/super.c:345
 #1: ffff88806defe198 (&sbi->vh_mutex){+.+.}-{4:4}, at: hfsplus_fill_super+0x1278/0x1b50 fs/hfsplus/super.c:552
 #2: ffff888053dd60b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x15a/0x1d0 fs/hfsplus/bfind.c:28
 #3: ffff888053d787c8 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1fc/0x1990 fs/hfsplus/extents.c:455
 #4: ffff88806defe0f8 (&sbi->alloc_mutex){+.+.}-{4:4}, at: hfsplus_block_allocate+0x94/0x9b0 fs/hfsplus/bitmap.c:35

stack backtrace:
CPU: 0 UID: 0 PID: 6377 Comm: syz.3.94 Not tainted 6.16.0-next-20250808-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_deadlock_bug+0x28b/0x2a0 kernel/locking/lockdep.c:3041
 check_deadlock kernel/locking/lockdep.c:3093 [inline]
 validate_chain+0x1a3f/0x2140 kernel/locking/lockdep.c:3895
 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
 __mutex_lock_common kernel/locking/mutex.c:598 [inline]
 __mutex_lock+0x187/0x1360 kernel/locking/mutex.c:760
 hfsplus_get_block+0x39e/0x1530 fs/hfsplus/extents.c:260
 block_read_full_folio+0x29c/0x830 fs/buffer.c:2420
 filemap_read_folio+0x114/0x380 mm/filemap.c:2413
 do_read_cache_folio+0x350/0x590 mm/filemap.c:3958
 do_read_cache_page mm/filemap.c:4024 [inline]
 read_cache_page+0x5d/0x170 mm/filemap.c:4033
 read_mapping_page include/linux/pagemap.h:991 [inline]
 hfsplus_block_allocate+0xe4/0x9b0 fs/hfsplus/bitmap.c:37
 hfsplus_file_extend+0xae3/0x1990 fs/hfsplus/extents.c:466
 hfsplus_bmap_reserve+0x122/0x500 fs/hfsplus/btree.c:358
 hfsplus_create_cat+0x183/0x1000 fs/hfsplus/catalog.c:272
 hfsplus_fill_super+0x12f5/0x1b50 fs/hfsplus/super.c:559
 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1692
 vfs_get_tree+0x8f/0x2b0 fs/super.c:1815
 do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805
 do_mount fs/namespace.c:4133 [inline]
 __do_sys_mount fs/namespace.c:4344 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4321
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f630ef9038a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f630fe72e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f630fe72ef0 RCX: 00007f630ef9038a
RDX: 0000200000000100 RSI: 0000200000002900 RDI: 00007f630fe72eb0
RBP: 0000200000000100 R08: 00007f630fe72ef0 R09: 0000000002804410
R10: 0000000002804410 R11: 0000000000000246 R12: 0000200000002900
R13: 00007f630fe72eb0 R14: 00000000000006e3 R15: 0000200000000c00
 </TASK>