============================================
WARNING: possible recursive locking detected
6.9.0-rc5-syzkaller #0 Not tainted
--------------------------------------------
syz-executor.1/8097 is trying to acquire lock:
ffff88804c2fc0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x183/0x220 fs/hfs/bfind.c:33

but task is already holding lock:
ffff88804c2fc0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x183/0x220 fs/hfs/bfind.c:33

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&tree->tree_lock/1);
  lock(&tree->tree_lock/1);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

5 locks held by syz-executor.1/8097:
 #0: ffff88804c2fa420 (sb_writers#14){.+.+}-{0:0}, at: do_sys_ftruncate fs/open.c:199 [inline]
 #0: ffff88804c2fa420 (sb_writers#14){.+.+}-{0:0}, at: __do_sys_ftruncate fs/open.c:207 [inline]
 #0: ffff88804c2fa420 (sb_writers#14){.+.+}-{0:0}, at: __se_sys_ftruncate fs/open.c:205 [inline]
 #0: ffff88804c2fa420 (sb_writers#14){.+.+}-{0:0}, at: __x64_sys_ftruncate+0xa9/0x110 fs/open.c:205
 #1: ffff8880434da9a8 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:795 [inline]
 #1: ffff8880434da9a8 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: do_truncate+0x14b/0x220 fs/open.c:63
 #2: ffff8880434da7f8 (&HFS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xa2/0xb10 fs/hfs/extent.c:397
 #3: ffff88804c2fc0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x183/0x220 fs/hfs/bfind.c:33
 #4: ffff8880434d9478 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xa2/0xb10 fs/hfs/extent.c:397

stack backtrace:
CPU: 3 PID: 8097 Comm: syz-executor.1 Not tainted 6.9.0-rc5-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 check_deadlock kernel/locking/lockdep.c:3062 [inline]
 validate_chain kernel/locking/lockdep.c:3856 [inline]
 __lock_acquire+0x20e6/0x3b30 kernel/locking/lockdep.c:5137
 lock_acquire kernel/locking/lockdep.c:5754 [inline]
 lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
 __mutex_lock_common kernel/locking/mutex.c:608 [inline]
 __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
 hfs_find_init+0x183/0x220 fs/hfs/bfind.c:33
 hfs_ext_read_extent+0x19c/0x9e0 fs/hfs/extent.c:200
 hfs_extend_file+0x4e4/0xb10 fs/hfs/extent.c:401
 hfs_bmap_reserve+0x29c/0x380 fs/hfs/btree.c:234
 __hfs_ext_write_extent+0x3cf/0x520 fs/hfs/extent.c:121
 __hfs_ext_cache_extent fs/hfs/extent.c:174 [inline]
 hfs_ext_read_extent+0x809/0x9e0 fs/hfs/extent.c:202
 hfs_extend_file+0x4e4/0xb10 fs/hfs/extent.c:401
 hfs_get_block+0x17f/0x830 fs/hfs/extent.c:353
 __block_write_begin_int+0x4fb/0x16e0 fs/buffer.c:2105
 __block_write_begin fs/buffer.c:2154 [inline]
 block_write_begin+0xb1/0x4a0 fs/buffer.c:2213
 cont_write_begin+0x53d/0x740 fs/buffer.c:2567
 hfs_write_begin+0x87/0x150 fs/hfs/inode.c:53
 cont_expand_zero fs/buffer.c:2494 [inline]
 cont_write_begin+0x333/0x740 fs/buffer.c:2557
 hfs_write_begin+0x87/0x150 fs/hfs/inode.c:53
 hfs_file_truncate+0xc11/0xfc0 fs/hfs/extent.c:494
 hfs_inode_setattr+0x48f/0x5d0 fs/hfs/inode.c:652
 notify_change+0x742/0x11c0 fs/attr.c:497
 do_truncate+0x15c/0x220 fs/open.c:65
 do_ftruncate+0x5e5/0x720 fs/open.c:181
 do_sys_ftruncate fs/open.c:199 [inline]
 __do_sys_ftruncate fs/open.c:207 [inline]
 __se_sys_ftruncate fs/open.c:205 [inline]
 __x64_sys_ftruncate+0xa9/0x110 fs/open.c:205
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc29747dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc2982350c8 EFLAGS: 00000246 ORIG_RAX: 000000000000004d
RAX: ffffffffffffffda RBX: 00007fc2975abf80 RCX: 00007fc29747dea9
RDX: 0000000000000000 RSI: 0000000002007ffb RDI: 0000000000000008
RBP: 00007fc2974ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fc2975abf80 R15: 00007ffcbfb7ce68
 </TASK>