------------[ cut here ]------------
WARNING: CPU: 0 PID: 20 at lib/radix-tree.c:572 delete_node+0x1f5/0xa60 lib/radix-tree.c:572
Modules linked in:
CPU: 0 UID: 0 PID: 20 Comm: rcuc/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:delete_node+0x1f5/0xa60 lib/radix-tree.c:572
Code: f8 48 c1 e8 03 0f b6 04 18 84 c0 75 22 41 80 3f 00 0f 85 c7 00 00 00 e8 f9 85 03 f7 4d 89 f7 e9 91 fe ff ff e8 ec 85 03 f7 90 <0f> 0b 90 eb b3 44 89 f9 80 e1 07 38 c1 7c d4 4c 89 ff e8 e4 3c 65
RSP: 0018:ffffc90000197920 EFLAGS: 00010293
RAX: ffffffff8abb3a24 RBX: dffffc0000000000 RCX: ffff88801b6e5a00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 1ffff1102866663a R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1dac5af R12: ffff8881433331d8
R13: 0000000004000004 R14: 0000000000000000 R15: ffff8880484f2698
FS:  0000000000000000(0000) GS:ffff888126df9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000397f4000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 radix_tree_delete_item+0x2b9/0x410 lib/radix-tree.c:1430
 afs_cell_destroy+0x16f/0x2c0 fs/afs/cell.c:523
 rcu_do_batch kernel/rcu/tree.c:2605 [inline]
 rcu_core kernel/rcu/tree.c:2861 [inline]
 rcu_cpu_kthread+0xbf6/0x1b50 kernel/rcu/tree.c:2949
 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>