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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
 __sanitizer_cov_trace_pc+0x0/0x50
 __should_failslab+0xee/0x130 mm/failslab.c:33
 should_failslab+0x9/0x14 mm/slab_common.c:1740
 slab_pre_alloc_hook mm/slab.h:503 [inline]
 slab_alloc mm/slab.c:3305 [inline]
 kmem_cache_alloc+0x29/0x5d0 mm/slab.c:3483
 skb_clone+0xf9/0x280 net/core/skbuff.c:1448
 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
 __tsan_read8+0xd/0x30 kernel/kcsan/kcsan.c:31
 ipt_do_table+0x22f/0xe40 net/ipv4/netfilter/ip_tables.c:264
 ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:56 [inline]
 iptable_mangle_hook+0x132/0x260 net/ipv4/netfilter/iptable_mangle.c:81
 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

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7212 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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