syzbot

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BUG: KCSAN: data-race in tick_nohz_next_event / tick_sched_timer

write to 0xffffffff838c2450 of 4 bytes by interrupt on cpu 1:
 tick_sched_do_timer kernel/time/tick-sched.c:191 [inline]
 tick_sched_timer+0x1f5/0x210 kernel/time/tick-sched.c:1414
 __run_hrtimer+0x160/0x480 kernel/time/hrtimer.c:1537
 __hrtimer_run_queues kernel/time/hrtimer.c:1601 [inline]
 hrtimer_interrupt+0x380/0xaf0 kernel/time/hrtimer.c:1663
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline]
 __sysvec_apic_timer_interrupt+0x6f/0x1c0 arch/x86/kernel/apic/apic.c:1106
 sysvec_apic_timer_interrupt+0x64/0x80 arch/x86/kernel/apic/apic.c:1100
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
 native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
 arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
 acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline]
 acpi_idle_do_entry drivers/acpi/processor_idle.c:553 [inline]
 acpi_idle_enter+0x258/0x2e0 drivers/acpi/processor_idle.c:688
 cpuidle_enter_state+0x2b6/0x750 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:158 [inline]
 cpuidle_idle_call kernel/sched/idle.c:239 [inline]
 do_idle+0x1a3/0x240 kernel/sched/idle.c:306
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:403
 secondary_startup_64_no_verify+0xb0/0xbb

read to 0xffffffff838c2450 of 4 bytes by task 0 on cpu 0:
 tick_nohz_next_event+0x217/0x300 kernel/time/tick-sched.c:838
 tick_nohz_get_sleep_length+0x121/0x280 kernel/time/tick-sched.c:1192
 menu_select+0x303/0x1040 drivers/cpuidle/governors/menu.c:283
 cpuidle_select+0x3d/0x50 drivers/cpuidle/cpuidle.c:322
 cpuidle_idle_call kernel/sched/idle.c:232 [inline]
 do_idle+0x16f/0x240 kernel/sched/idle.c:306
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:403
 rest_init+0xee/0x100 init/main.c:719
 arch_call_rest_init+0xa/0xb
 start_kernel+0x5ae/0x633 init/main.c:1125
 secondary_startup_64_no_verify+0xb0/0xbb

value changed: 0xffffffff -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.14.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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