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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
 is_atomic kernel/kcsan/core.c:169 [inline]
 should_watch kernel/kcsan/core.c:194 [inline]
 __kcsan_setup_watchpoint+0x57/0x510 kernel/kcsan/core.c:363
 __tsan_read1 kernel/kcsan/kcsan.c:28 [inline]
 __tsan_read1+0x2c/0x30 kernel/kcsan/kcsan.c:28
 skb_gro_incr_csum_unnecessary include/linux/netdevice.h:2744 [inline]
 tcp4_gro_receive+0x41a/0x4b0 net/ipv4/tcp_offload.c:310
 inet_gro_receive+0x7b5/0x800 net/ipv4/af_inet.c:1516
 dev_gro_receive+0xa05/0x1190 net/core/dev.c:5571
 napi_gro_receive+0x7c/0x330 net/core/dev.c:5704
 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061
 virtnet_receive drivers/net/virtio_net.c:1323 [inline]
 virtnet_poll+0x436/0x7d0 drivers/net/virtio_net.c:1428

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
 copy_user_enhanced_fast_string+0xe/0x20 arch/x86/lib/copy_user_64.S:204
 _copy_to_iter+0x170/0xa20 lib/iov_iter.c:610
 copy_to_iter include/linux/uio.h:138 [inline]
 simple_copy_to_iter+0x3f/0x60 net/core/datagram.c:515
 __skb_datagram_iter+0x28a/0x470 net/core/datagram.c:445
 skb_copy_datagram_iter+0x66/0x170 net/core/datagram.c:529
 skb_copy_datagram_msg include/linux/skbuff.h:3426 [inline]
 tcp_recvmsg+0x106c/0x1a30 net/ipv4/tcp.c:2132
 inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7397 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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