hfs: new node 0 already hashed?
------------[ cut here ]------------
WARNING: CPU: 0 PID: 37 at fs/hfs/bnode.c:520 hfs_bnode_create+0x461/0x4f0 fs/hfs/bnode.c:520
Modules linked in:
CPU: 0 UID: 0 PID: 37 Comm: kworker/u8:2 Tainted: G        W           6.16.0-syzkaller-12063-g37816488247d #0 PREEMPT_{RT,(full)} 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: writeback wb_workfn (flush-7:0)
RIP: 0010:hfs_bnode_create+0x461/0x4f0 fs/hfs/bnode.c:520
Code: 21 8b 89 ee e8 a0 fc 97 fe e9 cf fc ff ff e8 c6 07 2f ff 4c 89 ef e8 be 5e 68 08 48 c7 c7 20 5a 21 8b 89 ee e8 80 fc 97 fe 90 <0f> 0b 90 eb b0 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c d6 fb ff ff
RSP: 0018:ffffc90000ae6ba0 EFLAGS: 00010246
RAX: 000000000000001f RBX: ffff8880342b4000 RCX: bbc9f33ca1797000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff5200015cd19 R12: 0000000000000000
R13: ffff8880342b40d0 R14: ffff888024d9ac00 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881268cb000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6ddd637c00 CR3: 0000000010de4000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 hfs_bmap_alloc+0x5bb/0x640 fs/hfs/btree.c:326
 hfs_btree_inc_height+0xf6/0xac0 fs/hfs/brec.c:471
 hfs_brec_insert+0x743/0xbd0 fs/hfs/brec.c:148
 __hfs_ext_write_extent+0x2a1/0x470 fs/hfs/extent.c:124
 hfs_ext_write_extent+0x161/0x1e0 fs/hfs/extent.c:144
 hfs_write_inode+0x91/0x7d0 fs/hfs/inode.c:429
 write_inode fs/fs-writeback.c:1525 [inline]
 __writeback_single_inode+0x6f1/0x1000 fs/fs-writeback.c:1745
 writeback_sb_inodes+0x6b7/0xf60 fs/fs-writeback.c:1976
 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2047
 wb_writeback+0x44f/0xaf0 fs/fs-writeback.c:2158
 wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
 wb_do_writeback fs/fs-writeback.c:2315 [inline]
 wb_workfn+0xaf4/0xf00 fs/fs-writeback.c:2343
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>