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BUG: KCSAN: data-race in internal_add_timer / timer_clear_idle

write to 0xffff888237d176e5 of 1 bytes by task 0 on cpu 1:
 timer_clear_idle+0x1e/0x30 kernel/time/timer.c:1702
 tick_nohz_idle_retain_tick+0x31/0x40 kernel/time/tick-sched.c:1093
 cpuidle_idle_call kernel/sched/idle.c:237 [inline]
 do_idle+0x1e8/0x250 kernel/sched/idle.c:306
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:403
 secondary_startup_64_no_verify+0xb1/0xbb

read to 0xffff888237d176e5 of 1 bytes by interrupt on cpu 0:
 trigger_dyntick_cpu kernel/time/timer.c:569 [inline]
 enqueue_timer kernel/time/timer.c:601 [inline]
 internal_add_timer+0x22d/0x280 kernel/time/timer.c:611
 add_timer_on+0x262/0x2a0 kernel/time/timer.c:1182
 clocksource_watchdog+0xa74/0xac0 kernel/time/clocksource.c:478
 call_timer_fn+0x2e/0x1d0 kernel/time/timer.c:1421
 expire_timers+0x135/0x240 kernel/time/timer.c:1466
 __run_timers+0x378/0x440 kernel/time/timer.c:1734
 run_timer_softirq+0x19/0x30 kernel/time/timer.c:1747
 __do_softirq+0x12c/0x26e kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu kernel/softirq.c:636 [inline]
 irq_exit_rcu+0x4e/0xa0 kernel/softirq.c:648
 sysvec_apic_timer_interrupt+0x69/0x80 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20
 __tsan_read4+0x0/0x180 kernel/kcsan/core.c:634
 wait_consider_task+0x1bf/0x1a10 kernel/exit.c:1308
 do_wait_thread kernel/exit.c:1397 [inline]
 do_wait+0x182/0x640 kernel/exit.c:1514
 kernel_wait4+0x14b/0x1b0 kernel/exit.c:1677
 __do_sys_wait4 kernel/exit.c:1705 [inline]
 __se_sys_wait4 kernel/exit.c:1701 [inline]
 __x64_sys_wait4+0x90/0x120 kernel/exit.c:1701
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x01 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1121 Comm: syz-executor.0 Tainted: G        W         5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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