syzbot

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============================================
WARNING: possible recursive locking detected
6.17.0-rc1-syzkaller-00029-g91325f31afc1 #0 Not tainted
--------------------------------------------
syz-executor175/5862 is trying to acquire lock:
ffff888032fb60b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1

but task is already holding lock:
ffff888032fb60b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1

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-executor175/5862:
 #0: ffff888079436428 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3107 [inline]
 #0: ffff888079436428 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x211/0xb30 fs/read_write.c:682
 #1: ffff8880278f9620 (&sb->s_type->i_mutex_key#15){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
 #1: ffff8880278f9620 (&sb->s_type->i_mutex_key#15){+.+.}-{4:4}, at: generic_file_write_iter+0xeb/0x550 mm/filemap.c:4315
 #2: ffff8880278f9478 (&HFS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397
 #3: ffff888032fb60b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1
 #4: ffff8880278f80f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397

stack backtrace:
CPU: 1 UID: 0 PID: 5862 Comm: syz-executor175 Not tainted 6.17.0-rc1-syzkaller-00029-g91325f31afc1 #0 PREEMPT(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/mutex.c:598 [inline]
 __mutex_lock+0x187/0x1360 kernel/locking/mutex.c:760
 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_get_block+0x3d7/0xbd0 fs/hfs/extent.c:353
 __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2145
 block_write_begin fs/buffer.c:2256 [inline]
 cont_write_begin+0x789/0xb50 fs/buffer.c:2594
 hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:52
 generic_perform_write+0x2c5/0x900 mm/filemap.c:4175
 generic_file_write_iter+0x117/0x550 mm/filemap.c:4318
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x5c9/0xb30 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 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: 0033:0x7f12ae2b1fd9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffde545c718 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f12ae2fb09a RCX: 00007f12ae2b1fd9
RDX: 000000000208e24b RSI: 0000200000000080 RDI: 0000000000000005
RBP: 00007f12ae2fb0a2 R08: 00005555669de4c0 R09: 00005555669de4c0
R10: 00005555669de4c0 R11: 0000000000000246 R12: 00007ffde545c740
R13: 00007ffde545c968 R14: 431bde82d7b634db R15: 00007f12ae2fb03b
 </TASK>