rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (10500 ticks this GP) idle=5da/1/0x4000000000000000 softirq=17176/17176 fqs=5238 
	(t=10502 jiffies g=20689 q=549)
NMI backtrace for cpu 0
CPU: 0 PID: 13844 Comm: syz-executor.1 Not tainted 5.10.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x1e3/0x21e kernel/rcu/tree_stall.h:331
 print_cpu_stall kernel/rcu/tree_stall.h:563 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:637 [inline]
 rcu_pending kernel/rcu/tree.c:3694 [inline]
 rcu_sched_clock_irq.cold+0x472/0xee8 kernel/rcu/tree.c:2567
 update_process_times+0x77/0xd0 kernel/time/timer.c:1709
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176
 tick_sched_timer+0x1d1/0x2a0 kernel/time/tick-sched.c:1328
 __run_hrtimer kernel/time/hrtimer.c:1519 [inline]
 __hrtimer_run_queues+0x1ce/0xea0 kernel/time/hrtimer.c:1583
 hrtimer_interrupt+0x334/0x940 kernel/time/hrtimer.c:1645
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x540 arch/x86/kernel/apic/apic.c:1097
 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:91 [inline]
 sysvec_apic_timer_interrupt+0x48/0x100 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631
RIP: 0010:nf_conntrack_icmpv6_error+0x155/0x4e0 net/netfilter/nf_conntrack_proto_icmpv6.c:149
Code: e8 20 73 3b fa 4c 89 ea 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 08 03 00 00 45 8b 7d 00 <31> ff 44 89 fe e8 41 6b 3b fa 45 85 ff 75 78 e8 e7 72 3b fa 49 8d
RSP: 0018:ffffc90000007808 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 1ffff92000000f04 RCX: ffffffff873490fe
RDX: 1ffff92000000f62 RSI: ffffffff87349150 RDI: ffff88802c1fa488
RBP: ffff88802c1fa3c0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000001 R12: 0000000000000028
R13: ffffc90000007b10 R14: ffff88801adc1838 R15: 0000000000000003
 nf_conntrack_handle_icmp net/netfilter/nf_conntrack_core.c:1723 [inline]
 nf_conntrack_in.cold+0x128/0x176 net/netfilter/nf_conntrack_core.c:1818
 nf_hook_entry_hookfn include/linux/netfilter.h:136 [inline]
 nf_hook_slow+0xc5/0x1e0 net/netfilter/core.c:589
 nf_hook include/linux/netfilter.h:256 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ndisc_send_skb+0xb92/0x1720 net/ipv6/ndisc.c:508
 ndisc_send_rs+0x12e/0x700 net/ipv6/ndisc.c:702
 addrconf_rs_timer+0x3f2/0x820 net/ipv6/addrconf.c:3873
 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1410
 expire_timers kernel/time/timer.c:1455 [inline]
 __run_timers.part.0+0x67c/0xa50 kernel/time/timer.c:1747
 __run_timers kernel/time/timer.c:1728 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1760
 __do_softirq+0x2a0/0x9f6 kernel/softirq.c:298
 asm_call_irq_on_stack+0xf/0x20
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0xaa/0xd0 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:393 [inline]
 __irq_exit_rcu kernel/softirq.c:423 [inline]
 irq_exit_rcu+0x132/0x200 kernel/softirq.c:435
 sysvec_apic_timer_interrupt+0x4d/0x100 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631
RIP: 0010:rcu_read_unlock_special kernel/rcu/tree_plugin.h:641 [inline]
RIP: 0010:__rcu_read_unlock+0x1d3/0x470 kernel/rcu/tree_plugin.h:399
Code: ff a4 7e 81 e2 00 00 0f 00 0f 85 0b 02 00 00 4d 85 ed 74 62 84 c0 74 5e bf 09 00 00 00 e8 d5 7f e5 ff e8 00 d3 18 00 41 54 9d <e9> a5 fe ff ff 0f 0b 5b 5d 41 5c 41 5d 41 5e c3 e8 78 91 54 00 e9
RSP: 0018:ffffc90016b97768 EFLAGS: 00000246
RAX: 000000000103ded3 RBX: ffff8880b9e35780 RCX: ffffffff8155a917
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffffff8b33f980 R08: 0000000000000001 R09: ffffffff8ebb0677
R10: fffffbfff1d760ce R11: 0000000000000000 R12: 0000000000000246
R13: 0000000000000200 R14: 0000000000000001 R15: 000000000052b000
 rcu_read_unlock include/linux/rcupdate.h:694 [inline]
 __unlock_page_memcg mm/memcontrol.c:2191 [inline]
 unlock_page_memcg+0xa4/0x160 mm/memcontrol.c:2202
 zap_pte_range mm/memory.c:1253 [inline]
 zap_pmd_range mm/memory.c:1357 [inline]
 zap_pud_range mm/memory.c:1386 [inline]
 zap_p4d_range mm/memory.c:1407 [inline]
 unmap_page_range+0xe30/0x2640 mm/memory.c:1428
 unmap_single_vma+0x198/0x300 mm/memory.c:1473
 unmap_vmas+0x168/0x2e0 mm/memory.c:1505
 exit_mmap+0x2b1/0x530 mm/mmap.c:3220
 __mmput+0x122/0x470 kernel/fork.c:1079
 mmput+0x53/0x60 kernel/fork.c:1100
 exit_mm kernel/exit.c:486 [inline]
 do_exit+0xa72/0x29b0 kernel/exit.c:796
 do_group_exit+0x125/0x310 kernel/exit.c:906
 get_signal+0x42a/0x1f10 kernel/signal.c:2758
 arch_do_signal+0x82/0x2390 arch/x86/kernel/signal.c:811
 exit_to_user_mode_loop kernel/entry/common.c:161 [inline]
 exit_to_user_mode_prepare+0x100/0x1a0 kernel/entry/common.c:191
 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:279
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631
RIP: 0033:0x40ca29
Code: Unable to access opcode bytes at RIP 0x40c9ff.
RSP: 002b:00007f4bddf3fd00 EFLAGS: 00000207
RAX: 0000000000000001 RBX: 000000000119c0d8 RCX: 000000000045e159
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 000000000119c0dc
RBP: 000000000119c0d0 R08: 0000000000000009 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 000000000119c0dc
R13: 00007fff006fa44f R14: 00007f4bddf409c0 R15: 000000000119c0dc