syzbot

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BUG: KCSAN: data-race in tick_nohz_idle_stop_tick / tick_sched_do_timer

write to 0xffffffff85caf310 of 4 bytes by interrupt on cpu 0:
 tick_sched_do_timer+0xc0/0xe0 kernel/time/tick-sched.c:132
 tick_sched_timer+0x43/0xe0 kernel/time/tick-sched.c:1289
 __run_hrtimer kernel/time/hrtimer.c:1389 [inline]
 __hrtimer_run_queues+0x288/0x600 kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1509
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0xdc/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830

read to 0xffffffff85caf310 of 4 bytes by task 0 on cpu 1:
 tick_nohz_stop_tick kernel/time/tick-sched.c:757 [inline]
 __tick_nohz_idle_stop_tick kernel/time/tick-sched.c:949 [inline]
 tick_nohz_idle_stop_tick+0x193/0x670 kernel/time/tick-sched.c:970
 cpuidle_idle_call kernel/sched/idle.c:151 [inline]
 do_idle+0x1e0/0x2c0 kernel/sched/idle.c:263
 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:354
 start_secondary+0x207/0x260 arch/x86/kernel/smpboot.c:264
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xf5/0x159 lib/dump_stack.c:113
 panic+0x209/0x639 kernel/panic.c:219
 kcsan_report.cold+0xc/0x1b kernel/kcsan/report.c:303
 __kcsan_setup_watchpoint+0x3ee/0x510 kernel/kcsan/core.c:455
 __tsan_read4 kernel/kcsan/kcsan.c:30 [inline]
 __tsan_read4+0x2c/0x30 kernel/kcsan/kcsan.c:30
 tick_nohz_stop_tick kernel/time/tick-sched.c:757 [inline]
 __tick_nohz_idle_stop_tick kernel/time/tick-sched.c:949 [inline]
 tick_nohz_idle_stop_tick+0x193/0x670 kernel/time/tick-sched.c:970
 cpuidle_idle_call kernel/sched/idle.c:151 [inline]
 do_idle+0x1e0/0x2c0 kernel/sched/idle.c:263
 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:354
 start_secondary+0x207/0x260 arch/x86/kernel/smpboot.c:264
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241
Kernel Offset: disabled
Rebooting in 86400 seconds..