============================================
WARNING: possible recursive locking detected
syzkaller #0 Not tainted
--------------------------------------------
syz.7.609/9917 is trying to acquire lock:
ffff8880634be278 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_get_block+0x3a0/0x1670 fs/hfsplus/extents.c:262

but task is already holding lock:
ffff8880634bdaf8 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x21b/0x1dc0 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

6 locks held by syz.7.609/9917:
 #0: ffff888040092480 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
 #1: ffff8880634bce58 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline]
 #1: ffff8880634bce58 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: open_last_lookups fs/namei.c:4608 [inline]
 #1: ffff8880634bce58 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: path_openat+0xb5e/0x38a0 fs/namei.c:4855
 #2: ffff8880408d4178 (&sbi->vh_mutex){+.+.}-{4:4}, at: hfsplus_mknod+0x85/0x3f0 fs/hfsplus/dir.c:527
 #3: ffff88802414a0a0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28
 #4: ffff8880634bdaf8 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x21b/0x1dc0 fs/hfsplus/extents.c:455
 #5: ffff8880408d40e8 (&sbi->alloc_mutex){+.+.}-{4:4}, at: hfsplus_block_allocate+0xa7/0xce0 fs/hfsplus/bitmap.c:35

stack backtrace:
CPU: 0 UID: 0 PID: 9917 Comm: syz.7.609 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_deadlock_bug+0x279/0x290 kernel/locking/lockdep.c:3041
 check_deadlock kernel/locking/lockdep.c:3093 [inline]
 validate_chain kernel/locking/lockdep.c:3895 [inline]
 __lock_acquire+0x253f/0x2cf0 kernel/locking/lockdep.c:5237
 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
 __mutex_lock_common kernel/locking/rtmutex_api.c:534 [inline]
 mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:553
 hfsplus_get_block+0x3a0/0x1670 fs/hfsplus/extents.c:262
 block_read_full_folio+0x29f/0x830 fs/buffer.c:2310
 filemap_read_folio+0x137/0x3b0 mm/filemap.c:2501
 do_read_cache_folio+0x2bf/0x560 mm/filemap.c:4106
 do_read_cache_page mm/filemap.c:4172 [inline]
 read_cache_page+0x5d/0x170 mm/filemap.c:4181
 read_mapping_page include/linux/pagemap.h:1011 [inline]
 hfsplus_block_allocate+0xf3/0xce0 fs/hfsplus/bitmap.c:37
 hfsplus_file_extend+0xb21/0x1dc0 fs/hfsplus/extents.c:466
 hfsplus_bmap_reserve+0x183/0x5b0 fs/hfsplus/btree.c:510
 hfsplus_create_cat+0x1eb/0x11f0 fs/hfsplus/catalog.c:272
 hfsplus_mknod+0x186/0x3f0 fs/hfsplus/dir.c:538
 lookup_open fs/namei.c:4511 [inline]
 open_last_lookups fs/namei.c:4611 [inline]
 path_openat+0x13b4/0x38a0 fs/namei.c:4855
 do_file_open+0x23e/0x4a0 fs/namei.c:4887
 do_sys_openat2+0x113/0x200 fs/open.c:1364
 do_sys_open fs/open.c:1370 [inline]
 __do_sys_openat fs/open.c:1386 [inline]
 __se_sys_openat fs/open.c:1381 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1381
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2fcda7c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2fcbcd6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f2fcdcf5fa0 RCX: 00007f2fcda7c819
RDX: 0000000000080042 RSI: 0000200000000ac0 RDI: ffffffffffffff9c
RBP: 00007f2fcdb12c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000010 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2fcdcf6038 R14: 00007f2fcdcf5fa0 R15: 00007ffcd9f25648
 </TASK>