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BUG: KCSAN: data-race in tick_sched_do_timer / 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
 find_watchpoint kernel/kcsan/core.c:84 [inline]
 __kcsan_check_watchpoint+0x95/0x180 kernel/kcsan/core.c:322
 __tsan_read8+0x15/0x30 kernel/kcsan/kcsan.c:31
 nf_inet_addr_cmp include/linux/netfilter.h:31 [inline]
 __nf_ct_tuple_src_equal include/net/netfilter/nf_conntrack_tuple.h:127 [inline]
 nf_ct_tuple_equal include/net/netfilter/nf_conntrack_tuple.h:143 [inline]
 nf_ct_key_equal net/netfilter/nf_conntrack_core.c:695 [inline]
 ____nf_conntrack_find net/netfilter/nf_conntrack_core.c:752 [inline]
 __nf_conntrack_find_get+0x166/0x870 net/netfilter/nf_conntrack_core.c:778
 resolve_normal_ct net/netfilter/nf_conntrack_core.c:1548 [inline]
 nf_conntrack_in+0x2ef/0xaa0 net/netfilter/nf_conntrack_core.c:1710
 ipv4_conntrack_local+0xbe/0x130 net/netfilter/nf_conntrack_proto.c:200
 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
 nf_hook_slow+0x83/0x160 net/netfilter/core.c:512
 nf_hook include/linux/netfilter.h:260 [inline]
 __ip_local_out+0x1f7/0x2b0 net/ipv4/ip_output.c:114
 ip_local_out+0x31/0x90 net/ipv4/ip_output.c:123

read to 0xffffffff85caf310 of 4 bytes by interrupt on cpu 1:
 tick_sched_do_timer+0x33/0xe0 kernel/time/tick-sched.c:128
 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
 __sanitizer_cov_trace_const_cmp8+0x7/0x20 kernel/kcov.c:196
 select_estimate_accuracy+0x71/0x200 fs/select.c:87
 do_select+0xad7/0x1020 fs/select.c:502
 core_sys_select+0x38b/0x520 fs/select.c:677
 do_pselect fs/select.c:759 [inline]
 __do_sys_pselect6 fs/select.c:784 [inline]
 __se_sys_pselect6 fs/select.c:769 [inline]
 __x64_sys_pselect6+0x22a/0x280 fs/select.c:769
 do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7111 Comm: syz-fuzzer Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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