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ODEBUG: activate active (active state 0) object: ffff88806ac9e118 object type: rcu_head hint: 0x0
WARNING: lib/debugobjects.c:612 at debug_print_object+0x18e/0x2a0 lib/debugobjects.c:612, CPU#0: syz.2.303/7393
Modules linked in:
CPU: 0 UID: 0 PID: 7393 Comm: syz.2.303 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
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+0x19b/0x2a0 lib/debugobjects.c:612
Code: b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 4f 48 8d 3d b2 e4 df 0b 41 56 48 8b 14 dd 60 c6 f2 8b 4c 89 e6 <67> 48 0f b9 3a 58 83 05 dc 6d d6 0b 01 48 83 c4 18 5b 5d 41 5c 41
RSP: 0018:ffffc90000007ad8 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: ffffffff8bf2c5a0 RSI: ffffffff8bf2c100 RDI: ffffffff90929320
RBP: 0000000000000001 R08: ffff88806ac9e118 R09: ffffffff8b8f2ac0
R10: ffffffff9088ebd7 R11: ffffffff9aeab110 R12: ffffffff8bf2c100
R13: ffffffff8b8f2b00 R14: 0000000000000000 R15: ffffc90000007b98
FS:  0000000000000000(0000) GS:ffff8880976fc000(0063) knlGS:00000000f5435b40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f73a9154 CR3: 000000005f6cd000 CR4: 0000000000352ef0
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:3104
 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:580
 rcu_do_batch kernel/rcu/tree.c:2605 [inline]
 rcu_core+0x79c/0x15f0 kernel/rcu/tree.c:2857
 handle_softirqs+0x219/0x950 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:1056 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 96 27 21 f6 48 89 df e8 4e 7a 21 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 55 7d 11 f6 65 8b 05 2e d9 39 08 85 c0 74 16 5b
RSP: 0018:ffffc90003447808 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffff88804e85aa40 RCX: 0000000000000006
RDX: 0000000000000000 RSI: ffffffff8dacaa85 RDI: ffffffff8bf2b500
RBP: 0000000000000282 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff9088ebd7 R11: 0000000000000000 R12: ffff88804e85a890
R13: ffff88804e85aa80 R14: ffff88804e85a3e8 R15: ffff88804ea95540
 __unix_dgram_recvmsg+0x315/0xc30 net/unix/af_unix.c:2601
 unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2675
 sock_recvmsg_nosec net/socket.c:1078 [inline]
 ____sys_recvmsg+0x5f9/0x6b0 net/socket.c:2810
 ___sys_recvmsg+0x114/0x1a0 net/socket.c:2854
 do_recvmmsg+0x55d/0x750 net/socket.c:2941
 __sys_recvmmsg+0x21c/0x280 net/socket.c:3023
 __do_compat_sys_recvmmsg_time32 net/compat.c:418 [inline]
 __se_compat_sys_recvmmsg_time32 net/compat.c:414 [inline]
 __ia32_compat_sys_recvmmsg_time32+0xc4/0x160 net/compat.c:414
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xe8/0x680 arch/x86/entry/syscall_32.c:307
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:332
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f62579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f543555c EFLAGS: 00000296 ORIG_RAX: 0000000000000151
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000800000c0
RDX: 0000000000010106 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess):
   0:	b8 00 00 00 00       	mov    $0x0,%eax
   5:	00 fc                	add    %bh,%ah
   7:	ff                   	(bad)
   8:	df 48 89             	fisttps -0x77(%rax)
   b:	fa                   	cli
   c:	48 c1 ea 03          	shr    $0x3,%rdx
  10:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
  14:	75 4f                	jne    0x65
  16:	48 8d 3d b2 e4 df 0b 	lea    0xbdfe4b2(%rip),%rdi        # 0xbdfe4cf
  1d:	41 56                	push   %r14
  1f:	48 8b 14 dd 60 c6 f2 	mov    -0x740d39a0(,%rbx,8),%rdx
  26:	8b
  27:	4c 89 e6             	mov    %r12,%rsi
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	58                   	pop    %rax
  30:	83 05 dc 6d d6 0b 01 	addl   $0x1,0xbd66ddc(%rip)        # 0xbd66e13
  37:	48 83 c4 18          	add    $0x18,%rsp
  3b:	5b                   	pop    %rbx
  3c:	5d                   	pop    %rbp
  3d:	41 5c                	pop    %r12
  3f:	41                   	rex.B