rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (10500 ticks this GP) idle=1ee/1/0x4000000000000002 softirq=132584/132593 fqs=5249 
rcu: 	 (t=10502 jiffies g=179937 q=3316)
NMI backtrace for cpu 1
CPU: 1 PID: 32467 Comm: syz-executor4 Not tainted 4.19.0+ #311
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+0x244/0x39d lib/dump_stack.c:113
 nmi_cpu_backtrace.cold.1+0x5c/0xa1 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1b3/0x1ed lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:162 [inline]
 rcu_dump_cpu_stacks+0x16f/0x1bc kernel/rcu/tree.c:1195
 print_cpu_stall.cold.67+0x1f3/0x3c7 kernel/rcu/tree.c:1334
 check_cpu_stall kernel/rcu/tree.c:1408 [inline]
 rcu_pending kernel/rcu/tree.c:2961 [inline]
 rcu_check_callbacks+0xf3b/0x13f0 kernel/rcu/tree.c:2506
 update_process_times+0x2d/0x70 kernel/time/timer.c:1636
 tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:164
 tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1274
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0x41c/0x10d0 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x313/0x780 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1034 [inline]
 smp_apic_timer_interrupt+0x1a1/0x760 arch/x86/kernel/apic/apic.c:1059
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:801
 </IRQ>
RIP: 0010:arch_local_irq_enable arch/x86/include/asm/paravirt.h:771 [inline]
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x56/0x80 kernel/locking/spinlock.c:192
Code: 51 89 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 32 48 83 3d c3 d7 84 01 00 74 1f fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 40 6e 88 f9 65 8b 05 39 cb 34 78 85 c0 74 05 5b
RSP: 0018:ffff88017fc8fa00 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: ffff8801d2e18a48 RCX: 0000000000000000
RDX: 1ffffffff12a3f48 RSI: 0000000000000001 RDI: ffffffff8951fa40
RBP: ffff88017fc8fa08 R08: ffff88018355e440 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff8801d2e18300 R14: dffffc0000000000 R15: 0000000000000007
 spin_unlock_irq include/linux/spinlock.h:379 [inline]
 get_signal+0xf73/0x1980 kernel/signal.c:2520
 do_signal+0x9c/0x21c0 arch/x86/kernel/signal.c:816
 exit_to_usermode_loop+0x2e5/0x380 arch/x86/entry/common.c:162
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x401cf0
Code: 24 18 64 48 33 34 25 28 00 00 00 48 8d 04 11 75 11 48 83 c4 28 c3 bf 31 c2 4b 00 31 c0 e8 d8 f8 ff ff e8 33 94 05 00 0f 1f 00 <53> 48 8b 76 10 89 fb 64 8b 04 25 d0 ff ff ff 85 c0 74 3d 48 8d 86
RSP: 002b:00007f43a71043b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000119
RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000457569
RDX: 00007f43a71043c0 RSI: 00007f43a71044f0 RDI: 0000000000000007
RBP: 000000000072bf00 R08: 00000000200000c0 R09: 0000000000000008
R10: ffffffffffffffff R11: 0000000000000246 R12: 00007f43a71236d4
R13: 00000000004bdbb4 R14: 00000000004cc9d8 R15: 00000000ffffffff
sched: RT throttling activated