option from the mount to silence this warning.
=======================================================
hfsplus: xattr search failed
hfsplus: xattr searching failed
hfsplus: xattr searching failed
hfsplus: xattr searching failed
hfsplus: xattr searching failed
======================================================
WARNING: possible circular locking dependency detected
6.4.0-rc3-syzkaller-00015-g27e462c8fad4 #0 Not tainted
------------------------------------------------------
syz-executor226/4994 is trying to acquire lock:
ffff88807cdfe0b0 (&tree->tree_lock){+.+.}-{3:3}, at: hfsplus_file_truncate+0x811/0xb40 fs/hfsplus/extents.c:595

but task is already holding lock:
ffff888079102988 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_truncate+0x2da/0xb40 fs/hfsplus/extents.c:576

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}:
       lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5691
       __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603
       __mutex_lock kernel/locking/mutex.c:747 [inline]
       mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799
       hfsplus_file_extend+0x1d6/0x1b10 fs/hfsplus/extents.c:457
       hfsplus_bmap_reserve+0x105/0x4e0 fs/hfsplus/btree.c:358
       hfsplus_create_cat+0x1ad/0x1bb0 fs/hfsplus/catalog.c:272
       hfsplus_mknod+0x16a/0x2a0 fs/hfsplus/dir.c:494
       lookup_open fs/namei.c:3492 [inline]
       open_last_lookups fs/namei.c:3560 [inline]
       path_openat+0x13df/0x3170 fs/namei.c:3788
       do_filp_open+0x234/0x490 fs/namei.c:3818
       do_sys_openat2+0x13f/0x500 fs/open.c:1356
       do_sys_open fs/open.c:1372 [inline]
       __do_sys_openat fs/open.c:1388 [inline]
       __se_sys_openat fs/open.c:1383 [inline]
       __x64_sys_openat+0x247/0x290 fs/open.c:1383
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (&tree->tree_lock){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3108 [inline]
       check_prevs_add kernel/locking/lockdep.c:3227 [inline]
       validate_chain+0x166b/0x58e0 kernel/locking/lockdep.c:3842
       __lock_acquire+0x1295/0x2000 kernel/locking/lockdep.c:5074
       lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5691
       __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603
       __mutex_lock kernel/locking/mutex.c:747 [inline]
       mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799
       hfsplus_file_truncate+0x811/0xb40 fs/hfsplus/extents.c:595
       hfsplus_setattr+0x1bd/0x280 fs/hfsplus/inode.c:269
       notify_change+0xc8b/0xf40 fs/attr.c:483
       do_truncate+0x220/0x300 fs/open.c:66
       vfs_truncate+0x2e1/0x3a0 fs/open.c:112
       do_sys_truncate+0xde/0x190 fs/open.c:135
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&HFSPLUS_I(inode)->extents_lock);
                               lock(&tree->tree_lock);
                               lock(&HFSPLUS_I(inode)->extents_lock);
  lock(&tree->tree_lock);

 *** DEADLOCK ***

3 locks held by syz-executor226/4994:
 #0: ffff88807d522460 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:394
 #1: ffff888079102b80 (&sb->s_type->i_mutex_key#14){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
 #1: ffff888079102b80 (&sb->s_type->i_mutex_key#14){+.+.}-{3:3}, at: do_truncate+0x20c/0x300 fs/open.c:64
 #2: ffff888079102988 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_truncate+0x2da/0xb40 fs/hfsplus/extents.c:576

stack backtrace:
CPU: 0 PID: 4994 Comm: syz-executor226 Not tainted 6.4.0-rc3-syzkaller-00015-g27e462c8fad4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 check_noncircular+0x2fe/0x3b0 kernel/locking/lockdep.c:2188
 check_prev_add kernel/locking/lockdep.c:3108 [inline]
 check_prevs_add kernel/locking/lockdep.c:3227 [inline]
 validate_chain+0x166b/0x58e0 kernel/locking/lockdep.c:3842
 __lock_acquire+0x1295/0x2000 kernel/locking/lockdep.c:5074
 lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5691
 __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799
 hfsplus_file_truncate+0x811/0xb40 fs/hfsplus/extents.c:595
 hfsplus_setattr+0x1bd/0x280 fs/hfsplus/inode.c:269
 notify_change+0xc8b/0xf40 fs/attr.c:483
 do_truncate+0x220/0x300 fs/open.c:66
 vfs_truncate+0x2e1/0x3a0 fs/open.c:112
 do_sys_truncate+0xde/0x190 fs/open.c:135
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fca3e3ca7b9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 14 00 00 90 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002