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BUG: KCSAN: data-race in tick_do_update_jiffies64 / tick_do_update_jiffies64

write to 0xffffffff86042008 of 8 bytes by interrupt on cpu 0:
 tick_do_update_jiffies64+0x105/0x260 kernel/time/tick-sched.c:73
 tick_sched_do_timer+0xd4/0xe0 kernel/time/tick-sched.c:138
 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
 should_watch kernel/kcsan/core.c:188 [inline]
 __kcsan_setup_watchpoint+0xc3/0x510 kernel/kcsan/core.c:348
 __tsan_write4 kernel/kcsan/kcsan.c:30 [inline]
 __tsan_write4+0x32/0x40 kernel/kcsan/kcsan.c:30
 skb_reserve include/linux/skbuff.h:2323 [inline]
 __napi_alloc_skb+0xed/0x210 net/core/skbuff.c:535
 napi_alloc_skb include/linux/skbuff.h:2807 [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:6392 [inline]
 net_rx_action+0x3ae/0xa90 net/core/dev.c:6460

read to 0xffffffff86042008 of 8 bytes by interrupt on cpu 1:
 tick_do_update_jiffies64+0x2b/0x260 kernel/time/tick-sched.c:62
 tick_sched_do_timer+0xd4/0xe0 kernel/time/tick-sched.c:138
 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]
 arch_atomic64_read arch/x86/include/asm/atomic64_64.h:22 [inline]
 atomic64_read include/asm-generic/atomic-instrumented.h:925 [inline]
 atomic_long_read include/asm-generic/atomic-long.h:28 [inline]
 find_watchpoint kernel/kcsan/core.c:85 [inline]
 __kcsan_check_watchpoint+0xbb/0x180 kernel/kcsan/core.c:307
 __tsan_read4+0x15/0x30 kernel/kcsan/kcsan.c:30
 tcp_rcv_rtt_measure net/ipv4/tcp_input.c:560 [inline]
 tcp_event_data_recv+0x195/0x990 net/ipv4/tcp_input.c:684
 tcp_rcv_established+0xbfe/0xf50 net/ipv4/tcp_input.c:5662
 tcp_v4_do_rcv+0x381/0x4e0 net/ipv4/tcp_ipv4.c:1561
 sk_backlog_rcv include/net/sock.h:945 [inline]
 __release_sock+0x135/0x1e0 net/core/sock.c:2435

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7155 Comm: syz-fuzzer 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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