================================================================== 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 arch_local_irq_restore arch/x86/include/asm/paravirt.h:759 [inline] kcsan_setup_watchpoint+0x25a/0x440 kernel/kcsan/core.c:542 gro_list_prepare net/core/dev.c:5634 [inline] dev_gro_receive+0x234/0x10f0 net/core/dev.c:5740 napi_gro_receive+0x76/0x2f0 net/core/dev.c:5908 receive_buf+0x24c/0x3420 drivers/net/virtio_net.c:1073 virtnet_receive drivers/net/virtio_net.c:1335 [inline] virtnet_poll+0x343/0x790 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 find_watchpoint kernel/kcsan/core.c:107 [inline] check_access kernel/kcsan/core.c:566 [inline] __tsan_read4+0xa/0x110 kernel/kcsan/core.c:769 virtqueue_kick_prepare_split drivers/virtio/virtio_ring.c:609 [inline] virtqueue_kick_prepare+0x176/0x260 drivers/virtio/virtio_ring.c:1829 start_xmit+0x6a9/0xc00 drivers/net/virtio_net.c:1627 __netdev_start_xmit include/linux/netdevice.h:4533 [inline] netdev_start_xmit include/linux/netdevice.h:4547 [inline] xmit_one net/core/dev.c:3477 [inline] dev_hard_start_xmit+0xeb/0x420 net/core/dev.c:3493 sch_direct_xmit+0x2ae/0x8a0 net/sched/sch_generic.c:313 qdisc_restart net/sched/sch_generic.c:376 [inline] __qdisc_run+0x336/0xe10 net/sched/sch_generic.c:384 qdisc_run include/net/pkt_sched.h:134 [inline] qdisc_run include/net/pkt_sched.h:126 [inline] __dev_xmit_skb net/core/dev.c:3668 [inline] __dev_queue_xmit+0xfa5/0x1810 net/core/dev.c:4021 dev_queue_xmit+0x1e/0x30 net/core/dev.c:4085 neigh_hh_output include/net/neighbour.h:499 [inline] neigh_output include/net/neighbour.h:508 [inline] ip_finish_output2+0x87d/0xed0 net/ipv4/ip_output.c:228 __ip_finish_output net/ipv4/ip_output.c:306 [inline] __ip_finish_output+0x22f/0x460 net/ipv4/ip_output.c:288 ip_finish_output+0x3e/0x160 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip_output+0xf2/0x240 net/ipv4/ip_output.c:430 dst_output include/net/dst.h:435 [inline] ip_local_out+0x70/0x90 net/ipv4/ip_output.c:125 __ip_queue_xmit+0x3a6/0xa40 net/ipv4/ip_output.c:530 ip_queue_xmit+0x3e/0x50 include/net/ip.h:237 __tcp_transmit_skb+0xe0c/0x1d80 net/ipv4/tcp_output.c:1238 __tcp_send_ack+0x22c/0x2f0 net/ipv4/tcp_output.c:3779 tcp_send_ack+0x2d/0x40 net/ipv4/tcp_output.c:3785 tcp_cleanup_rbuf+0x124/0x340 net/ipv4/tcp.c:1575 tcp_recvmsg+0x686/0x1ba0 net/ipv4/tcp.c:2183 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: 8919 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 ==================================================================