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BUG: KCSAN: data-race in tick_nohz_next_event / tick_sched_do_timer

write to 0xffffffff85cb2790 of 4 bytes by interrupt on cpu 1:
 tick_sched_do_timer+0xc0/0xe0 kernel/time/tick-sched.c:132
 tick_sched_timer+0x43/0xe0 kernel/time/tick-sched.c:1292
 __run_hrtimer kernel/time/hrtimer.c:1514 [inline]
 __hrtimer_run_queues+0x288/0x600 kernel/time/hrtimer.c:1576
 hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1638
 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_once_size include/linux/compiler.h:227 [inline]
 arch_atomic64_read arch/x86/include/asm/atomic64_64.h:22 [inline]
 atomic64_read include/asm-generic/atomic-instrumented.h:850 [inline]
 atomic_long_read include/asm-generic/atomic-long.h:28 [inline]
 find_watchpoint kernel/kcsan/core.c:64 [inline]
 __kcsan_check_watchpoint+0xba/0x180 kernel/kcsan/core.c:266
 __tsan_read8+0x15/0x30 kernel/kcsan/kcsan.c:36
 ifname_compare_aligned include/linux/netfilter/x_tables.h:411 [inline]
 ip_packet_match net/ipv4/netfilter/ip_tables.c:59 [inline]
 ipt_do_table+0x3e4/0xe60 net/ipv4/netfilter/ip_tables.c:284
 iptable_raw_hook+0x4a/0x60 net/ipv4/netfilter/iptable_raw.c:44
 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
 __ip_queue_xmit+0x3a8/0xa40 net/ipv4/ip_output.c:532

read to 0xffffffff85cb2790 of 4 bytes by task 0 on cpu 0:
 tick_nohz_next_event+0x1a4/0x380 kernel/time/tick-sched.c:725
 __tick_nohz_idle_stop_tick kernel/time/tick-sched.c:943 [inline]
 tick_nohz_idle_stop_tick+0x3c2/0x670 kernel/time/tick-sched.c:973
 cpuidle_idle_call kernel/sched/idle.c:151 [inline]
 do_idle+0x1a5/0x280 kernel/sched/idle.c:263
 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:355
 rest_init+0xec/0xf6 init/main.c:452
 arch_call_rest_init+0x17/0x37
 start_kernel+0x838/0x85e init/main.c:786
 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:472
 x86_64_start_kernel+0x72/0x76 arch/x86/kernel/head64.c:453
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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