loop0: detected capacity change from 0 to 1024
============================================
WARNING: possible recursive locking detected
6.16.0-rc5-syzkaller-gec4801305969 #0 Not tainted
--------------------------------------------
syz.0.38/6809 is trying to acquire lock:
ffff0000d12b1548 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_get_block+0x2bc/0x1154 fs/hfsplus/extents.c:260

but task is already holding lock:
ffff0000d12b07c8 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1b8/0x1388 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

5 locks held by syz.0.38/6809:
 #0: ffff0000d0c400e0 (&type->s_umount_key#58/1){+.+.}-{4:4}, at: alloc_super+0x1a0/0x80c fs/super.c:345
 #1: ffff0000ce6a4998 (&sbi->vh_mutex){+.+.}-{4:4}, at: hfsplus_fill_super+0xf64/0x1714 fs/hfsplus/super.c:554
 #2: ffff0000d08880b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x144/0x1bc fs/hfsplus/bfind.c:28
 #3: ffff0000d12b07c8 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1b8/0x1388 fs/hfsplus/extents.c:458
 #4: ffff0000ce6a48f8 (&sbi->alloc_mutex){+.+.}-{4:4}, at: hfsplus_block_allocate+0x88/0x70c fs/hfsplus/bitmap.c:35

stack backtrace:
CPU: 0 UID: 0 PID: 6809 Comm: syz.0.38 Not tainted 6.16.0-rc5-syzkaller-gec4801305969 #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)
 __dump_stack+0x30/0x40 lib/dump_stack.c:94
 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
 dump_stack+0x1c/0x28 lib/dump_stack.c:129
 print_deadlock_bug+0x2e8/0x2f0 kernel/locking/lockdep.c:3044
 check_deadlock kernel/locking/lockdep.c:3096 [inline]
 validate_chain kernel/locking/lockdep.c:3898 [inline]
 __lock_acquire+0x2940/0x30a4 kernel/locking/lockdep.c:5240
 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5871
 __mutex_lock_common+0x1d0/0x2190 kernel/locking/mutex.c:602
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799
 hfsplus_get_block+0x2bc/0x1154 fs/hfsplus/extents.c:260
 block_read_full_folio+0x2ec/0x824 fs/buffer.c:2427
 hfsplus_read_folio+0x28/0x38 fs/hfsplus/inode.c:28
 filemap_read_folio+0xec/0x2f8 mm/filemap.c:2412
 do_read_cache_folio+0x364/0x5bc mm/filemap.c:3894
 do_read_cache_page mm/filemap.c:3960 [inline]
 read_cache_page+0x6c/0x160 mm/filemap.c:3969
 read_mapping_page include/linux/pagemap.h:966 [inline]
 hfsplus_block_allocate+0xdc/0x70c fs/hfsplus/bitmap.c:37
 hfsplus_file_extend+0x770/0x1388 fs/hfsplus/extents.c:469
 hfsplus_bmap_reserve+0xe8/0x494 fs/hfsplus/btree.c:358
 hfsplus_create_cat+0x170/0xdc8 fs/hfsplus/catalog.c:272
 hfsplus_fill_super+0xfbc/0x1714 fs/hfsplus/super.c:561
 get_tree_bdev_flags+0x360/0x414 fs/super.c:1681
 get_tree_bdev+0x2c/0x3c fs/super.c:1704
 hfsplus_get_tree+0x28/0x38 fs/hfsplus/super.c:640
 vfs_get_tree+0x90/0x28c fs/super.c:1804
 do_new_mount+0x228/0x814 fs/namespace.c:3902
 path_mount+0x5b4/0xde0 fs/namespace.c:4226
 do_mount fs/namespace.c:4239 [inline]
 __do_sys_mount fs/namespace.c:4450 [inline]
 __se_sys_mount fs/namespace.c:4427 [inline]
 __arm64_sys_mount+0x3e8/0x468 fs/namespace.c:4427
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x58/0x180 arch/arm64/kernel/entry-common.c:879
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596