------------[ cut here ]------------
ODEBUG: activate active (active state 0) object: ffff8880347deed8 object type: rcu_head hint: 0x0
WARNING: CPU: 2 PID: 0 at lib/debugobjects.c:612 debug_print_object+0x1a2/0x2b0 lib/debugobjects.c:612
Modules linked in:
CPU: 2 UID: 0 PID: 0 Comm: swapper/2 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:debug_print_object+0x1a2/0x2b0 lib/debugobjects.c:612
Code: fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 54 41 56 48 8b 14 dd a0 22 d0 8b 4c 89 e6 48 c7 c7 20 17 d0 8b e8 3f b0 d1 fc 90 <0f> 0b 90 90 58 83 05 56 5a b7 0b 01 48 83 c4 18 5b 5d 41 5c 41 5d
RSP: 0018:ffffc90000648ad8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000003 RCX: ffffffff8179bd78
RDX: ffff88801d6cc900 RSI: ffffffff8179bd85 RDI: 0000000000000001
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8bd01d40
R13: ffffffff8b6ec6a0 R14: 0000000000000000 R15: ffffc90000648b98
FS:  0000000000000000(0000) GS:ffff8880d7085000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000009000 CR3: 000000006496b000 CR4: 0000000000352ef0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 debug_object_activate+0x2bc/0x4c0 lib/debugobjects.c:842
 debug_rcu_head_queue kernel/rcu/rcu.h:236 [inline]
 __call_rcu_common.constprop.0+0x35/0xa10 kernel/rcu/tree.c:3108
 radix_tree_node_free lib/radix-tree.c:310 [inline]
 delete_node+0x1fc/0x8d0 lib/radix-tree.c:573
 __radix_tree_delete+0x193/0x3d0 lib/radix-tree.c:1379
 radix_tree_delete_item+0xea/0x230 lib/radix-tree.c:1430
 afs_cell_destroy+0x1db/0x310 fs/afs/cell.c:523
 rcu_do_batch kernel/rcu/tree.c:2605 [inline]
 rcu_core+0x799/0x1530 kernel/rcu/tree.c:2861
 handle_softirqs+0x219/0x8e0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: ae 60 02 e9 d3 09 03 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d 13 2e 1e 00 fb f4 <c3> cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000187df8 EFLAGS: 00000286
RAX: 0000000000e45eab RBX: 0000000000000002 RCX: ffffffff8b4bda89
RDX: 0000000000000000 RSI: ffffffff8d820d97 RDI: ffffffff8bd011c0
RBP: ffffed1003ad9920 R08: 0000000000000001 R09: ffffed100d506655
R10: ffff88806a8332ab R11: 0000000000000000 R12: 0000000000000002
R13: ffff88801d6cc900 R14: ffffffff905f3590 R15: 0000000000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:757
 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:190 [inline]
 do_idle+0x38d/0x500 kernel/sched/idle.c:330
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428
 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315
 common_startup_64+0x13e/0x148
 </TASK>
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	02 e9                	add    %cl,%ch
   2:	d3 09                	rorl   %cl,(%rcx)
   4:	03 00                	add    (%rax),%eax
   6:	0f 1f 00             	nopl   (%rax)
   9:	90                   	nop
   a:	90                   	nop
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	f3 0f 1e fa          	endbr64
  1d:	eb 07                	jmp    0x26
  1f:	0f 00 2d 13 2e 1e 00 	verw   0x1e2e13(%rip)        # 0x1e2e39
  26:	fb                   	sti
  27:	f4                   	hlt
* 28:	c3                   	ret <-- trapping instruction
  29:	cc                   	int3
  2a:	cc                   	int3
  2b:	cc                   	int3
  2c:	cc                   	int3
  2d:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
  34:	00 00 00
  37:	66 90                	xchg   %ax,%ax
  39:	90                   	nop
  3a:	90                   	nop
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop