rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=6a6/1/0x4000000000000000 softirq=9991/9992 fqs=3087 
	(t=10501 jiffies g=10949 q=35980)
NMI backtrace for cpu 0
CPU: 0 PID: 8132 Comm: syz-executor609 Not tainted 5.9.0-rc2-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+0x18f/0x20d lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x194/0x1cf kernel/rcu/tree_stall.h:318
 print_cpu_stall kernel/rcu/tree_stall.h:551 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:625 [inline]
 rcu_pending kernel/rcu/tree.c:3637 [inline]
 rcu_sched_clock_irq.cold+0x5b3/0xccd kernel/rcu/tree.c:2519
 update_process_times+0x25/0xa0 kernel/time/timer.c:1710
 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:1524 [inline]
 __hrtimer_run_queues+0x1d5/0xfc0 kernel/time/hrtimer.c:1588
 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1650
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0x142/0x5e0 arch/x86/kernel/apic/apic.c:1097
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline]
 sysvec_apic_timer_interrupt+0x4c/0xf0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
RIP: 0010:dst_alloc+0x94/0x641 net/core/dst.c:93
Code: 00 00 e8 4f 08 35 fb 48 8d 7b 78 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 16 05 00 00 48 8b 7b 78 <be> 20 0a 00 00 e8 12 c1 74 fb 48 85 c0 49 89 c4 0f 84 74 04 00 00
RSP: 0018:ffffc900000079b0 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffff8880938f0bc0 RCX: ffffffff863f3b13
RDX: 1ffff1101271e187 RSI: ffffffff863f36c1 RDI: ffff88821569af00
RBP: 0000000000000000 R08: 0000000000000000 R09: ffff888091354aa0
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff86ec1bf0
R13: ffff888083f7c000 R14: 0000000000000001 R15: 00000000ffffffff
 ip6_dst_alloc+0x2e/0x100 net/ipv6/route.c:356
 icmp6_dst_alloc+0x6d/0x6c0 net/ipv6/route.c:3166
 ndisc_send_skb+0x1207/0x1720 net/ipv6/ndisc.c:486
 ndisc_send_rs+0x12e/0x700 net/ipv6/ndisc.c:700
 addrconf_rs_timer+0x2ec/0x7c0 net/ipv6/addrconf.c:3873
 call_timer_fn+0x1ac/0x760 kernel/time/timer.c:1413
 expire_timers kernel/time/timer.c:1458 [inline]
 __run_timers.part.0+0x67c/0xaa0 kernel/time/timer.c:1755
 __run_timers kernel/time/timer.c:1736 [inline]
 run_timer_softirq+0xae/0x1a0 kernel/time/timer.c:1768
 __do_softirq+0x2de/0xa24 kernel/softirq.c:298
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline]
 do_softirq_own_stack+0x9d/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+0x1f3/0x230 kernel/softirq.c:435
 sysvec_apic_timer_interrupt+0x51/0xf0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x4b/0x80 kernel/locking/spinlock.c:199
Code: c0 d8 3b b6 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 31 48 83 3d 46 16 c0 01 00 74 25 fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 db 8d 59 f9 65 8b 05 d4 d8 0b 78 85 c0 74 02 5d
RSP: 0018:ffffc90009e675b0 EFLAGS: 00000286
RAX: 1ffffffff136c77b RBX: ffff8880913541c0 RCX: 1ffffffff1563f41
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff87f6256f
RBP: ffff8880ae635e00 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880ae635e00
R13: ffff8880a9630240 R14: 0000000000000000 R15: 0000000000000001
 finish_lock_switch kernel/sched/core.c:3517 [inline]
 finish_task_switch+0x147/0x750 kernel/sched/core.c:3617
 context_switch kernel/sched/core.c:3781 [inline]
 __schedule+0x8ed/0x21e0 kernel/sched/core.c:4527
 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:4683
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:40
 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:183
 spin_unlock include/linux/spinlock.h:394 [inline]
 zap_pte_range mm/memory.c:1147 [inline]
 zap_pmd_range mm/memory.c:1195 [inline]
 zap_pud_range mm/memory.c:1224 [inline]
 zap_p4d_range mm/memory.c:1245 [inline]
 unmap_page_range+0x1602/0x2b20 mm/memory.c:1266
 unmap_single_vma+0x198/0x300 mm/memory.c:1311
 unmap_vmas+0x168/0x2e0 mm/memory.c:1343
 exit_mmap+0x2b1/0x530 mm/mmap.c:3183
 __mmput+0x122/0x470 kernel/fork.c:1076
 mmput+0x53/0x60 kernel/fork.c:1097
 exit_mm kernel/exit.c:483 [inline]
 do_exit+0xa8b/0x29f0 kernel/exit.c:793
 do_group_exit+0x125/0x310 kernel/exit.c:903
 get_signal+0x428/0x1f00 kernel/signal.c:2757
 arch_do_signal+0x82/0x2520 arch/x86/kernel/signal.c:811
 exit_to_user_mode_loop kernel/entry/common.c:136 [inline]
 exit_to_user_mode_prepare+0x15d/0x1c0 kernel/entry/common.c:167
 syscall_exit_to_user_mode+0x59/0x2b0 kernel/entry/common.c:242
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x444499
Code: Bad RIP value.
RSP: 002b:00007ffe8843c418 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: 0000000000000004 RBX: 0000000000000003 RCX: 0000000000444499
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000040
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000400326777
R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000000002
R13: 0000000000405190 R14: 0000000000000000 R15: 0000000000000000