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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
 __tsan_read4+0x1/0x30 kernel/kcsan/kcsan.c:30
 napi_poll net/core/dev.c:6352 [inline]
 net_rx_action+0x3ae/0xa50 net/core/dev.c:6418
 __do_softirq+0x115/0x33f kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0xbb/0xe0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:537 [inline]
 do_IRQ+0xdf/0x150 arch/x86/kernel/irq.c:259
 ret_from_intr+0x0/0x19
 is_atomic kernel/kcsan/core.c:165 [inline]
 should_watch kernel/kcsan/core.c:194 [inline]
 __kcsan_setup_watchpoint+0x3c/0x510 kernel/kcsan/core.c:363
 __tsan_write8 kernel/kcsan/kcsan.c:31 [inline]
 __tsan_write8+0x32/0x40 kernel/kcsan/kcsan.c:31

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
 find_watchpoint kernel/kcsan/core.c:94 [inline]
 __kcsan_check_watchpoint+0xed/0x180 kernel/kcsan/core.c:322
 __tsan_read8+0x15/0x30 kernel/kcsan/kcsan.c:31
 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+0x3d7/0xe40 net/ipv4/netfilter/ip_tables.c:284
 iptable_filter_hook+0x4a/0x60 net/ipv4/netfilter/iptable_filter.c:37
 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

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7294 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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