======================================================= ============================================ 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: 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