syzbot

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BUG: KCSAN: data-race in tick_nohz_next_event / tick_nohz_stop_tick

write to 0xffffffff86fc18d0 of 4 bytes by task 0 on cpu 1:
 tick_nohz_stop_tick+0x99/0x410 kernel/time/tick-sched.c:789
 __tick_nohz_idle_stop_tick kernel/time/tick-sched.c:981 [inline]
 tick_nohz_idle_stop_tick+0x148/0x2e0 kernel/time/tick-sched.c:1002
 cpuidle_idle_call kernel/sched/idle.c:209 [inline]
 do_idle+0x176/0x230 kernel/sched/idle.c:273
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:369
 secondary_startup_64_no_verify+0xb0/0xbb

read to 0xffffffff86fc18d0 of 4 bytes by task 0 on cpu 0:
 tick_nohz_next_event+0x217/0x300 kernel/time/tick-sched.c:754
 tick_nohz_get_sleep_length+0x121/0x270 kernel/time/tick-sched.c:1107
 menu_select+0x2fa/0xf40 drivers/cpuidle/governors/menu.c:283
 cpuidle_select+0x3d/0x50 drivers/cpuidle/cpuidle.c:322
 cpuidle_idle_call kernel/sched/idle.c:206 [inline]
 do_idle+0x15f/0x230 kernel/sched/idle.c:273
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:369
 rest_init+0xd7/0xe0 init/main.c:721
 arch_call_rest_init+0xa/0xb
 start_kernel+0x5a0/0x625 init/main.c:1061
 secondary_startup_64_no_verify+0xb0/0xbb

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.10.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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