hfs: new node 0 already hashed?
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1
WARNING: fs/hfs/bnode.c:520 at hfs_bnode_create.cold+0x41/0x49 fs/hfs/bnode.c:520, CPU#0: kworker/u8:0/13586
Modules linked in:
CPU: 0 UID: 0 PID: 13586 Comm: kworker/u8:0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: writeback wb_workfn (flush-7:3)
RIP: 0010:hfs_bnode_create.cold+0x41/0x49 fs/hfs/bnode.c:520
Code: 0d 99 6a 0a e9 bf 86 d0 01 e8 93 58 e1 00 4c 89 f7 e8 fb 98 6a 0a e8 86 58 e1 00 89 ee 48 c7 c7 00 7c d1 8b e8 e8 e3 fa ff 90 <0f> 0b 90 e9 c1 89 d0 01 e8 6a 58 e1 00 e8 15 fb 4d 00 e9 1d 8c d0
RSP: 0018:ffffc9000e4e7030 EFLAGS: 00010282
RAX: 000000000000001f RBX: ffff888028f64300 RCX: 0000000000000000
RDX: 000000000000001f RSI: ffffffff81e7aae9 RDI: fffff52001c9cdf7
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000000 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888035dea000 R14: ffff888035dea0e0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88812433f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff4e95456b8 CR3: 000000007c991000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 hfs_bmap_alloc+0x5a7/0x6b0 fs/hfs/btree.c:326
 hfs_btree_inc_height.isra.0+0xff/0x820 fs/hfs/brec.c:490
 hfs_brec_insert+0x8ba/0xc20 fs/hfs/brec.c:148
 __hfs_ext_write_extent+0x3ef/0x510 fs/hfs/extent.c:124
 hfs_ext_write_extent+0x1b7/0x200 fs/hfs/extent.c:144
 hfs_write_inode+0xce/0xab0 fs/hfs/inode.c:459
 write_inode fs/fs-writeback.c:1582 [inline]
 __writeback_single_inode+0xd00/0x13c0 fs/fs-writeback.c:1813
 writeback_sb_inodes+0x766/0x1c70 fs/fs-writeback.c:2042
 wb_writeback+0x1c0/0xbe0 fs/fs-writeback.c:2227
 wb_do_writeback fs/fs-writeback.c:2374 [inline]
 wb_workfn+0x142/0xc00 fs/fs-writeback.c:2414
 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
 process_scheduled_works kernel/workqueue.c:3359 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>