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BUG: KCSAN: data-race in tick_sched_do_timer / tick_sched_do_timer

write to 0xffffffff8764e210 of 4 bytes by interrupt on cpu 1:
 tick_sched_do_timer+0xb4/0xd0 kernel/time/tick-sched.c:141
 tick_sched_timer+0x3f/0xd0 kernel/time/tick-sched.c:1313
 __run_hrtimer kernel/time/hrtimer.c:1520 [inline]
 __hrtimer_run_queues+0x271/0x600 kernel/time/hrtimer.c:1584
 hrtimer_interrupt+0x226/0x490 kernel/time/hrtimer.c:1646
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1113 [inline]
 smp_apic_timer_interrupt+0xd8/0x270 arch/x86/kernel/apic/apic.c:1138
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 find_watchpoint kernel/kcsan/core.c:127 [inline]
 check_access kernel/kcsan/core.c:566 [inline]
 __tsan_read4+0x61/0x110 kernel/kcsan/core.c:769
 virtqueue_add_split drivers/virtio/virtio_ring.c:502 [inline]
 virtqueue_add+0x89c/0x1ab0 drivers/virtio/virtio_ring.c:1706
 virtqueue_add_inbuf_ctx+0x4c/0x64 drivers/virtio/virtio_ring.c:1809
 add_recvbuf_mergeable drivers/net/virtio_net.c:1213 [inline]
 try_fill_recv+0x69a/0xe60 drivers/net/virtio_net.c:1235
 virtnet_receive drivers/net/virtio_net.c:1347 [inline]
 virtnet_poll+0x62d/0x790 drivers/net/virtio_net.c:1440
 napi_poll net/core/dev.c:6571 [inline]
 net_rx_action+0x3ad/0xac0 net/core/dev.c:6639
 __do_softirq+0x118/0x34a kernel/softirq.c:292
 run_ksoftirqd+0x41/0x60 kernel/softirq.c:604
 smpboot_thread_fn+0x374/0x4a0 kernel/smpboot.c:165
 kthread+0x203/0x230 kernel/kthread.c:268
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

read to 0xffffffff8764e210 of 4 bytes by interrupt on cpu 0:
 tick_sched_do_timer+0x2e/0xd0 kernel/time/tick-sched.c:137
 tick_sched_timer+0x3f/0xd0 kernel/time/tick-sched.c:1313
 __run_hrtimer kernel/time/hrtimer.c:1520 [inline]
 __hrtimer_run_queues+0x271/0x600 kernel/time/hrtimer.c:1584
 hrtimer_interrupt+0x226/0x490 kernel/time/hrtimer.c:1646
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1113 [inline]
 smp_apic_timer_interrupt+0xd8/0x270 arch/x86/kernel/apic/apic.c:1138
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 is_atomic kernel/kcsan/core.c:229 [inline]
 should_watch kernel/kcsan/core.c:257 [inline]
 check_access kernel/kcsan/core.c:581 [inline]
 __tsan_read4+0xac/0x110 kernel/kcsan/core.c:769
 skb_try_coalesce+0x26d/0xb90 net/core/skbuff.c:5149
 tcp_try_coalesce net/ipv4/tcp_input.c:4443 [inline]
 tcp_try_coalesce+0x219/0x430 net/ipv4/tcp_input.c:4422
 tcp_queue_rcv+0x9b/0x380 net/ipv4/tcp_input.c:4697
 tcp_rcv_established+0xba3/0xee0 net/ipv4/tcp_input.c:5682
 tcp_v4_do_rcv+0x396/0x4f0 net/ipv4/tcp_ipv4.c:1621
 sk_backlog_rcv include/net/sock.h:996 [inline]
 __release_sock+0x130/0x1e0 net/core/sock.c:2460
 release_sock+0x5e/0x160 net/core/sock.c:2976
 tcp_recvmsg+0x68e/0x1ba0 net/ipv4/tcp.c:2185
 inet_recvmsg+0xc1/0x250 net/ipv4/af_inet.c:838
 sock_recvmsg_nosec net/socket.c:886 [inline]
 sock_recvmsg net/socket.c:904 [inline]
 sock_recvmsg+0x8e/0xb0 net/socket.c:900
 sock_read_iter+0x185/0x230 net/socket.c:982
 call_read_iter include/linux/fs.h:1901 [inline]
 new_sync_read+0x416/0x450 fs/read_write.c:415
 __vfs_read+0x9e/0xb0 fs/read_write.c:428
 vfs_read fs/read_write.c:462 [inline]
 vfs_read+0x13e/0x2b0 fs/read_write.c:447
 ksys_read+0x16a/0x1a0 fs/read_write.c:588
 __do_sys_read fs/read_write.c:598 [inline]
 __se_sys_read fs/read_write.c:596 [inline]
 __x64_sys_read+0x49/0x60 fs/read_write.c:596
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8903 Comm: syz-fuzzer Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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