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BUG: KCSAN: data-race in tick_sched_do_timer / tick_sched_do_timer

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:84 [inline]
 __kcsan_check_watchpoint+0xa3/0x180 kernel/kcsan/core.c:322
 __tsan_read8+0x15/0x30 kernel/kcsan/kcsan.c:31
 __copy_skb_header+0xac/0x2c0 net/core/skbuff.c:935
 __skb_clone+0x79/0x380 net/core/skbuff.c:987
 skb_clone+0x128/0x280 net/core/skbuff.c:1455
 skb_share_check include/linux/skbuff.h:1675 [inline]
 packet_rcv_spkt+0x2e2/0x350 net/packet/af_packet.c:1816
 deliver_skb net/core/dev.c:1969 [inline]
 deliver_ptype_list_skb net/core/dev.c:1984 [inline]
 __netif_receive_skb_core+0xe13/0x1a90 net/core/dev.c:4962
 __netif_receive_skb_one_core+0x67/0xe0 net/core/dev.c:5002

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
 ipv4_mtu+0x1/0x250 net/ipv4/route.c:1303
 ip_finish_output+0x41/0x160 net/ipv4/ip_output.c:318
 NF_HOOK_COND include/linux/netfilter.h:294 [inline]
 ip_output+0xdf/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
 ip_queue_xmit+0x45/0x60 include/net/ip.h:236
 __tcp_transmit_skb+0xdeb/0x1cd0 net/ipv4/tcp_output.c:1158

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7286 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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