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BUG: KCSAN: data-race in tick_sched_do_timer / tick_sched_do_timer

write to 0xffffffff85cb2790 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: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]
 check_kcov_mode kernel/kcov.c:70 [inline]
 __sanitizer_cov_trace_pc+0x26/0x50 kernel/kcov.c:102
 __nf_ct_ext_find include/net/netfilter/nf_conntrack_extend.h:67 [inline]
 nf_ct_ecache_find include/net/netfilter/nf_conntrack_ecache.h:35 [inline]
 nf_ct_deliver_cached_events+0xe1/0x2a0 net/netfilter/nf_conntrack_ecache.c:192
 nf_conntrack_confirm include/net/netfilter/nf_conntrack_core.h:65 [inline]
 nf_confirm+0x27d/0x2b0 net/netfilter/nf_conntrack_proto.c:154
 ipv4_confirm+0xcf/0x160 net/netfilter/nf_conntrack_proto.c:169
 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]
 NF_HOOK_COND include/linux/netfilter.h:293 [inline]
 ip_output+0x1d3/0x210 net/ipv4/ip_output.c:432
 dst_output include/net/dst.h:436 [inline]
 ip_local_out+0x74/0x90 net/ipv4/ip_output.c:125
 __ip_queue_xmit+0x3a8/0xa40 net/ipv4/ip_output.c:532

read to 0xffffffff85cb2790 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: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
 get_current arch/x86/include/asm/current.h:15 [inline]
 write_comp_data+0x9/0x70 kernel/kcov.c:122
 skb_pull_inline include/linux/skbuff.h:2245 [inline]
 eth_type_trans+0xac/0x3d0 net/ethernet/eth.c:165
 receive_buf+0x265/0x30b0 drivers/net/virtio_net.c:1057
 virtnet_receive drivers/net/virtio_net.c:1323 [inline]
 virtnet_poll+0x436/0x7d0 drivers/net/virtio_net.c:1428
 napi_poll net/core/dev.c:6392 [inline]
 net_rx_action+0x3ae/0xa90 net/core/dev.c:6460
 __do_softirq+0x115/0x33f kernel/softirq.c:292
 run_ksoftirqd+0x46/0x60 kernel/softirq.c:603

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 16 Comm: ksoftirqd/1 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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