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BUG: KCSAN: data-race in tick_sched_do_timer / tick_sched_do_timer

write to 0xffffffff85cb26d0 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+0x274/0x5f0 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
 find_watchpoint kernel/kcsan/core.c:67 [inline]
 check_access kernel/kcsan/core.c:388 [inline]
 __tsan_unaligned_write4+0x51/0x1f0 kernel/kcsan/core.c:529
 arch_atomic_set arch/x86/include/asm/atomic.h:43 [inline]
 atomic_set include/asm-generic/atomic-instrumented.h:58 [inline]
 refcount_set include/linux/refcount.h:32 [inline]
 __build_skb_around+0x79/0x1b0 net/core/skbuff.c:271
 __build_skb+0x63/0x80 net/core/skbuff.c:316
 __napi_alloc_skb+0x18a/0x210 net/core/skbuff.c:523
 napi_alloc_skb include/linux/skbuff.h:2823 [inline]
 page_to_skb+0x8d/0x480 drivers/net/virtio_net.c:384
 receive_mergeable drivers/net/virtio_net.c:924 [inline]
 receive_buf+0x17c7/0x30b0 drivers/net/virtio_net.c:1033
 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:6311 [inline]
 net_rx_action+0x3ae/0xa90 net/core/dev.c:6379
 __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:536 [inline]
 do_IRQ+0xa6/0x180 arch/x86/kernel/irq.c:263
 ret_from_intr+0x0/0x19

read to 0xffffffff85cb26d0 of 4 bytes by interrupt on cpu 0:
 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+0x274/0x5f0 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
 native_safe_halt+0xe/0x10 arch/x86/kernel/paravirt.c:71
 arch_cpu_idle+0x1f/0x30 arch/x86/kernel/process.c:571
 default_idle_call+0x1e/0x40 kernel/sched/idle.c:94
 cpuidle_idle_call kernel/sched/idle.c:154 [inline]
 do_idle+0x1af/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:490
 x86_64_start_kernel+0x72/0x76 arch/x86/kernel/head64.c:471
 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-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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