syzbot

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BUG: KCSAN: data-race in tick_nohz_stop_tick / tick_sched_timer

write to 0xffffffff88164bd0 of 4 bytes by task 0 on cpu 1:
 tick_nohz_stop_tick+0xa0/0x440 kernel/time/tick-sched.c:789
 __tick_nohz_idle_stop_tick kernel/time/tick-sched.c:981 [inline]
 tick_nohz_idle_stop_tick+0xf2/0x1c0 kernel/time/tick-sched.c:1002
 cpuidle_idle_call kernel/sched/idle.c:209 [inline]
 do_idle+0x1ca/0x2c0 kernel/sched/idle.c:273
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:369
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243

read to 0xffffffff88164bd0 of 4 bytes by interrupt on cpu 0:
 tick_sched_do_timer kernel/time/tick-sched.c:137 [inline]
 tick_sched_timer+0x41/0x230 kernel/time/tick-sched.c:1321
 __run_hrtimer+0x154/0x4b0 kernel/time/hrtimer.c:1524
 __hrtimer_run_queues kernel/time/hrtimer.c:1588 [inline]
 hrtimer_interrupt+0x37c/0xa40 kernel/time/hrtimer.c:1650
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0xa3/0x280 arch/x86/kernel/apic/apic.c:1097
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 __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]
 sysvec_apic_timer_interrupt+0x80/0xd0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
 native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60
 arch_safe_halt arch/x86/include/asm/paravirt.h:150 [inline]
 acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
 acpi_idle_do_entry+0x94/0x120 drivers/acpi/processor_idle.c:517
 acpi_idle_enter+0x22e/0x260 drivers/acpi/processor_idle.c:648
 cpuidle_enter_state+0x2ba/0x840 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:350
 call_cpuidle kernel/sched/idle.c:132 [inline]
 cpuidle_idle_call kernel/sched/idle.c:213 [inline]
 do_idle+0x1e7/0x2c0 kernel/sched/idle.c:273
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:369
 rest_init+0xd8/0xe0 init/main.c:709
 arch_call_rest_init+0xa/0xb
 start_kernel+0x608/0x6d0 init/main.c:1049
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.9.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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