rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10499 ticks this GP) idle=1e2/1/0x4000000000000000 softirq=12500/12500 fqs=53 
	(t=10500 jiffies g=11073 q=1475)
rcu: rcu_preempt kthread starved for 10378 jiffies! g11073 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:29176 pid:   13 ppid:     2 flags:0x00004000
Call Trace:
 context_switch kernel/sched/core.c:4327 [inline]
 __schedule+0x90c/0x21a0 kernel/sched/core.c:5078
 schedule+0xcf/0x270 kernel/sched/core.c:5157
 schedule_timeout+0x148/0x250 kernel/time/timer.c:1878
 rcu_gp_fqs_loop kernel/rcu/tree.c:1940 [inline]
 rcu_gp_kthread+0xbbe/0x1d70 kernel/rcu/tree.c:2113
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
NMI backtrace for cpu 1
CPU: 1 PID: 10040 Comm: syz-executor.0 Not tainted 5.11.0-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:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 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+0x1f4/0x230 kernel/rcu/tree_stall.h:337
 print_cpu_stall kernel/rcu/tree_stall.h:569 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:643 [inline]
 rcu_pending kernel/rcu/tree.c:3751 [inline]
 rcu_sched_clock_irq.cold+0x48e/0xedf kernel/rcu/tree.c:2580
 update_process_times+0x16d/0x200 kernel/time/timer.c:1782
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226
 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1369
 __run_hrtimer kernel/time/hrtimer.c:1519 [inline]
 __hrtimer_run_queues+0x1c0/0xe40 kernel/time/hrtimer.c:1583
 hrtimer_interrupt+0x334/0x940 kernel/time/hrtimer.c:1645
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x540 arch/x86/kernel/apic/apic.c:1106
 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:1100
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:629
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:197
Code: 00 00 00 4d 8b 0b 48 0f bd c8 49 8b 14 24 48 63 c9 e9 66 ff ff ff 4c 01 ca 49 89 13 e9 00 fd ff ff 66 0f 1f 84 00 00 00 00 00 <65> 8b 05 19 1b 8f 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b
RSP: 0018:ffffc90000db0998 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff88801c29b780 RDI: 0000000000000003
RBP: ffff8880247e1140 R08: 0000000000000000 R09: 0000000000000001
R10: ffffffff87adcd1f R11: 0000000000000002 R12: ffff88801d274780
R13: ffff888076a2b100 R14: ffff88801d2747d8 R15: ffff88801985e480
 rcu_read_lock include/linux/rcupdate.h:646 [inline]
 ip6_mtu+0x17f/0x470 net/ipv6/route.c:3103
 dst_mtu include/net/dst.h:198 [inline]
 ip6_skb_dst_mtu include/net/ip6_route.h:271 [inline]
 __ip6_finish_output net/ipv6/ip6_output.c:173 [inline]
 __ip6_finish_output+0x26e/0xe10 net/ipv6/ip6_output.c:161
 ip6_finish_output+0x35/0x200 net/ipv6/ip6_output.c:192
 NF_HOOK_COND include/linux/netfilter.h:290 [inline]
 ip6_output+0x1db/0x520 net/ipv6/ip6_output.c:215
 dst_output include/net/dst.h:441 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ndisc_send_skb+0xa90/0x1750 net/ipv6/ndisc.c:508
 ndisc_send_rs+0x12e/0x700 net/ipv6/ndisc.c:702
 addrconf_rs_timer+0x3f2/0x820 net/ipv6/addrconf.c:3875
 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1417
 expire_timers kernel/time/timer.c:1462 [inline]
 __run_timers.part.0+0x67c/0xa50 kernel/time/timer.c:1731
 __run_timers kernel/time/timer.c:1712 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1744
 __do_softirq+0x29b/0x9f6 kernel/softirq.c:343
 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:226 [inline]
 __irq_exit_rcu kernel/softirq.c:420 [inline]
 irq_exit_rcu+0x134/0x200 kernel/softirq.c:432
 sysvec_apic_timer_interrupt+0x4d/0x100 arch/x86/kernel/apic/apic.c:1100
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:629
RIP: 0010:get_lock_parent_ip include/linux/ftrace.h:846 [inline]
RIP: 0010:preempt_latency_start kernel/sched/core.c:4714 [inline]
RIP: 0010:preempt_latency_start kernel/sched/core.c:4711 [inline]
RIP: 0010:preempt_count_add+0xb6/0x140 kernel/sched/core.c:4739
Code: 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 81 00 00 00 48 89 9d 80 13 00 00 5b 5d c3 31 ff 31 db e8 0a 7e 0b 00 <eb> c0 e8 93 f2 ac 07 85 c0 74 93 48 c7 c0 18 bb a3 8d 48 ba 00 00
RSP: 0018:ffffc9000200fe00 EFLAGS: 00000217
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff1f7e6cc
RDX: 0000000000000000 RSI: ffffffff81c51efe RDI: 0000000000000000
RBP: ffff88801d2b5930 R08: 0000000000000000 R09: ffff8880170ab267
R10: ffffffff81c51ee4 R11: 0000000000000001 R12: ffff88801d2b5900
R13: 0000000000040000 R14: ffff88801d2b5930 R15: ffff88801d2b5980
 __raw_spin_lock include/linux/spinlock_api_smp.h:141 [inline]
 _raw_spin_lock+0xe/0x40 kernel/locking/spinlock.c:151
 spin_lock include/linux/spinlock.h:354 [inline]
 setfl fs/fcntl.c:79 [inline]
 do_fcntl+0x696/0x1070 fs/fcntl.c:347
 __do_sys_fcntl fs/fcntl.c:463 [inline]
 __se_sys_fcntl fs/fcntl.c:448 [inline]
 __x64_sys_fcntl+0x165/0x1e0 fs/fcntl.c:448
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x465d99
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fdc7ea3b188 EFLAGS: 00000246 ORIG_RAX: 0000000000000048
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465d99
RDX: 0000000000042000 RSI: 0000000000000004 RDI: 0000000000000003
RBP: 00000000004bcf27 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffd7aade8cf R14: 00007fdc7ea3b300 R15: 0000000000022000