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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 0:
 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_read2+0x15/0x30 kernel/kcsan/kcsan.c:29
 __netif_receive_skb_core+0x1c3/0x1a90 net/core/dev.c:4847
 __netif_receive_skb_one_core+0x67/0xe0 net/core/dev.c:5002
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5118
 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5208
 napi_skb_finish net/core/dev.c:5671 [inline]
 napi_gro_receive+0x28f/0x330 net/core/dev.c:5704
 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061

write to 0xffffffff85caf310 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: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
 watchpoint_slot kernel/kcsan/encoding.h:82 [inline]
 find_watchpoint kernel/kcsan/core.c:75 [inline]
 __kcsan_check_watchpoint+0x71/0x180 kernel/kcsan/core.c:322
 __tsan_read8+0x15/0x30 kernel/kcsan/kcsan.c:31
 __sk_stream_memory_free include/net/sock.h:1213 [inline]
 __sk_stream_memory_free include/net/sock.h:1208 [inline]
 __sk_stream_is_writeable include/net/sock.h:1225 [inline]
 sk_stream_is_writeable include/net/sock.h:1230 [inline]
 tcp_poll+0x47d/0x6b0 net/ipv4/tcp.c:558
 sock_poll+0xed/0x250 net/socket.c:1256
 vfs_poll include/linux/poll.h:90 [inline]
 ep_item_poll.isra.0+0x90/0x190 fs/eventpoll.c:892
 ep_send_events_proc+0x113/0x5c0 fs/eventpoll.c:1749
 ep_scan_ready_list.constprop.0+0x189/0x500 fs/eventpoll.c:704

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7233 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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