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BUG: KCSAN: data-race in internal_add_timer / timer_clear_idle

write to 0xffff88813bd1bce5 of 1 bytes by task 0 on cpu 1:
 timer_clear_idle+0x1e/0x30 kernel/time/timer.c:1692
 tick_nohz_restart_sched_tick kernel/time/tick-sched.c:868 [inline]
 __tick_nohz_idle_restart_tick+0x20/0x180 kernel/time/tick-sched.c:1169
 tick_nohz_idle_exit+0xfc/0x210 kernel/time/tick-sched.c:1210
 do_idle+0x1f6/0x230 kernel/sched/idle.c:286
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:369
 secondary_startup_64_no_verify+0xb0/0xbb

read to 0xffff88813bd1bce5 of 1 bytes by interrupt on cpu 0:
 trigger_dyntick_cpu kernel/time/timer.c:568 [inline]
 enqueue_timer kernel/time/timer.c:599 [inline]
 internal_add_timer+0x219/0x2a0 kernel/time/timer.c:609
 __mod_timer+0x789/0xbf0 kernel/time/timer.c:1060
 mod_timer+0x1b/0x20 kernel/time/timer.c:1106
 sk_reset_timer+0x1f/0xa0 net/core/sock.c:2933
 tcp_send_delayed_ack+0x23e/0x250 net/ipv4/tcp_output.c:3925
 __tcp_ack_snd_check+0x2f6/0x500 net/ipv4/tcp_input.c:5406
 tcp_rcv_established+0x11bc/0x1450 net/ipv4/tcp_input.c:5835
 tcp_v4_do_rcv+0x278/0x4a0 net/ipv4/tcp_ipv4.c:1652
 tcp_v4_rcv+0x2101/0x2370 net/ipv4/tcp_ipv4.c:2034
 ip_protocol_deliver_rcu+0x1f9/0x3e0 net/ipv4/ip_input.c:204
 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ip_local_deliver+0x1c0/0x280 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:449 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:550 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:600 [inline]
 ip_sublist_rcv+0x4c4/0x590 net/ipv4/ip_input.c:608
 ip_list_rcv+0x262/0x290 net/ipv4/ip_input.c:643
 __netif_receive_skb_list_ptype net/core/dev.c:5358 [inline]
 __netif_receive_skb_list_core+0x34b/0x450 net/core/dev.c:5406
 __netif_receive_skb_list+0x262/0x2e0 net/core/dev.c:5458
 netif_receive_skb_list_internal+0xda/0x330 net/core/dev.c:5568
 gro_normal_list net/core/dev.c:5722 [inline]
 napi_complete_done+0x1b2/0x420 net/core/dev.c:6447
 virtqueue_napi_complete+0x28/0x80 drivers/net/virtio_net.c:334
 virtnet_poll+0x607/0x730 drivers/net/virtio_net.c:1460
 napi_poll+0x178/0x4c0 net/core/dev.c:6763
 net_rx_action+0x17a/0x480 net/core/dev.c:6833
 __do_softirq+0x12c/0x2b1 kernel/softirq.c:298
 asm_call_irq_on_stack+0xf/0x20
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0x32/0x40 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:393 [inline]
 __irq_exit_rcu+0xb2/0xc0 kernel/softirq.c:423
 common_interrupt+0xb5/0x130 arch/x86/kernel/irq.c:239
 asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:622
 native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline]
 arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline]
 acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
 acpi_idle_do_entry drivers/acpi/processor_idle.c:517 [inline]
 acpi_idle_enter+0x25b/0x2e0 drivers/acpi/processor_idle.c:648
 cpuidle_enter_state+0x2bd/0x750 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:132 [inline]
 cpuidle_idle_call kernel/sched/idle.c:213 [inline]
 do_idle+0x193/0x230 kernel/sched/idle.c:273
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:369
 rest_init+0xd7/0xe0 init/main.c:721
 arch_call_rest_init+0xa/0xb
 start_kernel+0x5a0/0x625 init/main.c:1061
 secondary_startup_64_no_verify+0xb0/0xbb

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.10.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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