============================================
WARNING: possible recursive locking detected
syzkaller #0 Not tainted
--------------------------------------------
syz.1.53/6319 is trying to acquire lock:
ffff8880311b96e8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397

but task is already holding lock:
ffff8880311b9e28 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397

other info that might help us de[  146.584771][ T6319] 
other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&HFS_I(tree->inode)->extents_lock);
  lock(&HFS_I(tree->inode)->extents_lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

5 locks held by syz.1.53/6319:
 #0: ffff888062d32488 (sb_writers#26){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
 #1: ffff8880311ba740 (&type->i_mutex_dir_key#17){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
 #1: ffff8880311ba740 (&type->i_mutex_dir_key#17){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:3804 [inline]
 #1: ffff8880311ba740 (&type->i_mutex_dir_key#17){+.+.}-{4:4}, at: path_openat+0x8e6/0x3840 fs/namei.c:4043
 #2: ffff8880397b80a0 (&tree->tree_lock){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1
 #3: ffff8880311b9e28 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397
 #4: ffff8880239300a0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1

stack backtrace:
CPU: 0 UID: 0 PID: 6319 Comm: syz.1.53 Not tainted syzkaller #0 PREEMPT_{RT,(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/rtmutex_api.c:535 [inline]
 mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:547
 hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397
 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269
 __hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121
 __hfs_ext_cache_extent+0x6b/0x9b0 fs/hfs/extent.c:174
 hfs_ext_read_extent fs/hfs/extent.c:202 [inline]
 hfs_extend_file+0x316/0x1230 fs/hfs/extent.c:401
 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269
 hfs_cat_create+0x1b3/0x640 fs/hfs/catalog.c:104
 hfs_create+0x66/0xe0 fs/hfs/dir.c:202
 lookup_open fs/namei.c:3708 [inline]
 open_last_lookups fs/namei.c:3807 [inline]
 path_openat+0x14fd/0x3840 fs/namei.c:4043
 do_filp_open+0x1fa/0x410 fs/namei.c:4073
 do_sys_openat2+0x121/0x1c0 fs/open.c:1435
 do_sys_open fs/open.c:1450 [inline]
 __do_sys_open fs/open.c:1458 [inline]
 __se_sys_open fs/open.c:1454 [inline]
 __x64_sys_open+0x11e/0x150 fs/open.c:1454
 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: 0033:0x7f0356a5ebe9
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:00007f0354cbe038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f0356c85fa0 RCX: 00007f0356a5ebe9
RDX: 0000000000000000 RSI: 000000000014957e RDI: 0000200000000180
RBP: 00007f0356ae1e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0356c86038 R14: 00007f0356c85fa0 R15: 00007ffc6925e678
 </TASK>
------------[ cut here ]------------
rtmutex deadlock detected
WARNING: CPU: 0 PID: 6319 at kernel/locking/rtmutex.c:1674 rt_mutex_handle_deadlock+0x28/0xb0 kernel/locking/rtmutex.c:1674
Modules linked in:
CPU: 0 UID: 0 PID: 6319 Comm: syz.1.53 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:rt_mutex_handle_deadlock+0x28/0xb0 kernel/locking/rtmutex.c:1674
Code: 90 90 41 57 41 56 41 55 41 54 53 83 ff dd 0f 85 8c 00 00 00 48 89 f7 e8 c6 2c 01 00 90 48 c7 c7 80 08 0b 8b e8 79 98 8a f6 90 <0f> 0b 90 90 4c 8d 3d 00 00 00 00 65 48 8b 1c 25 08 e0 f5 91 4c 8d
RSP: 0018:ffffc90006ad6f50 EFLAGS: 00010246
RAX: 736c97d69eac6c00 RBX: ffffc90006ad6fe0 RCX: ffff888031a98000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90006ad70e8 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed1017104863 R12: 1ffff92000d5adf8
R13: ffffffff8af89119 R14: ffff888023930048 R15: dffffc0000000000
FS:  00007f0354cbe6c0(0000) GS:ffff8881268c2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f183684c000 CR3: 000000003b332000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1734 [inline]
 __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline]
 rt_mutex_slowlock+0x692/0x6e0 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 __mutex_lock_common kernel/locking/rtmutex_api.c:536 [inline]
 mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:547
 hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1
 hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
 hfs_extend_file+0x2ee/0x1230 fs/hfs/extent.c:401
 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269
 __hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121
 __hfs_ext_cache_extent+0x6b/0x9b0 fs/hfs/extent.c:174
 hfs_ext_read_extent fs/hfs/extent.c:202 [inline]
 hfs_extend_file+0x316/0x1230 fs/hfs/extent.c:401
 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269
 hfs_cat_create+0x1b3/0x640 fs/hfs/catalog.c:104
 hfs_create+0x66/0xe0 fs/hfs/dir.c:202
 lookup_open fs/namei.c:3708 [inline]
 open_last_lookups fs/namei.c:3807 [inline]
 path_openat+0x14fd/0x3840 fs/namei.c:4043
 do_filp_open+0x1fa/0x410 fs/namei.c:4073
 do_sys_openat2+0x121/0x1c0 fs/open.c:1435
 do_sys_open fs/open.c:1450 [inline]
 __do_sys_open fs/open.c:1458 [inline]
 __se_sys_open fs/open.c:1454 [inline]
 __x64_sys_open+0x11e/0x150 fs/open.c:1454
 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: 0033:0x7f0356a5ebe9
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:00007f0354cbe038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f0356c85fa0 RCX: 00007f0356a5ebe9
RDX: 0000000000000000 RSI: 000000000014957e RDI: 0000200000000180
RBP: 00007f0356ae1e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0356c86038 R14: 00007f0356c85fa0 R15: 00007ffc6925e678
 </TASK>