================================================================== BUG: KCSAN: data-race in timer_clear_idle / trigger_dyntick_cpu.isra.0 write to 0xffff88812c11dbe4 of 1 bytes by task 0 on cpu 1: timer_clear_idle+0x3d/0x50 kernel/time/timer.c:1676 tick_nohz_restart_sched_tick kernel/time/tick-sched.c:854 [inline] __tick_nohz_idle_restart_tick+0x32/0x1a0 kernel/time/tick-sched.c:1155 tick_nohz_idle_exit+0x19c/0x1d0 kernel/time/tick-sched.c:1196 do_idle+0xac/0x290 kernel/sched/idle.c:282 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:361 start_secondary+0x164/0x1b0 arch/x86/kernel/smpboot.c:264 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242 read to 0xffff88812c11dbe4 of 1 bytes by interrupt on cpu 0: trigger_dyntick_cpu.isra.0+0x6d/0xf0 kernel/time/timer.c:577 __mod_timer kernel/time/timer.c:1052 [inline] mod_timer+0x50e/0x830 kernel/time/timer.c:1101 sk_reset_timer+0x29/0xc0 net/core/sock.c:2840 tcp_send_delayed_ack+0x1fd/0x280 net/ipv4/tcp_output.c:3734 __tcp_ack_snd_check+0x3bb/0x550 net/ipv4/tcp_input.c:5268 tcp_ack_snd_check net/ipv4/tcp_input.c:5309 [inline] tcp_rcv_established+0x72b/0xee0 net/ipv4/tcp_input.c:5730 tcp_v4_do_rcv+0x396/0x4f0 net/ipv4/tcp_ipv4.c:1619 tcp_v4_rcv+0x1bbf/0x1d80 net/ipv4/tcp_ipv4.c:2001 ip_protocol_deliver_rcu+0x4b/0x410 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0xf3/0x120 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_local_deliver+0x135/0x220 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_sublist_rcv_finish+0xf0/0x140 net/ipv4/ip_input.c:549 ip_list_rcv_finish net/ipv4/ip_input.c:599 [inline] ip_sublist_rcv+0x3f8/0x530 net/ipv4/ip_input.c:607 ip_list_rcv+0x2f3/0x321 net/ipv4/ip_input.c:642 __netif_receive_skb_list_ptype net/core/dev.c:5241 [inline] __netif_receive_skb_list_ptype net/core/dev.c:5230 [inline] __netif_receive_skb_list_core+0x368/0x5c0 net/core/dev.c:5289 __netif_receive_skb_list net/core/dev.c:5341 [inline] netif_receive_skb_list_internal+0x5c7/0x810 net/core/dev.c:5436 gro_normal_list.part.0+0x37/0xa0 net/core/dev.c:5547 gro_normal_list net/core/dev.c:5560 [inline] gro_normal_one+0x14c/0x160 net/core/dev.c:5559 napi_skb_finish net/core/dev.c:5887 [inline] napi_gro_receive+0x27d/0x2f0 net/core/dev.c:5919 receive_buf+0x24e/0x2e20 drivers/net/virtio_net.c:1061 virtnet_receive drivers/net/virtio_net.c:1323 [inline] virtnet_poll+0x343/0x790 drivers/net/virtio_net.c:1428 napi_poll net/core/dev.c:6582 [inline] net_rx_action+0x3ad/0xac0 net/core/dev.c:6650 __do_softirq+0x118/0x34a kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0xb5/0xd0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:546 [inline] do_IRQ+0x7b/0x120 arch/x86/kernel/irq.c:263 ret_from_intr+0x0/0x21 native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60 arch_safe_halt arch/x86/include/asm/paravirt.h:144 [inline] default_idle+0x21/0x170 arch/x86/kernel/process.c:695 cpuidle_idle_call kernel/sched/idle.c:154 [inline] do_idle+0x1b7/0x290 kernel/sched/idle.c:269 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:361 rest_init+0xe4/0xeb init/main.c:632 arch_call_rest_init+0x13/0x2b start_kernel+0xcc2/0xceb init/main.c:971 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.6.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================