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BUG: KCSAN: data-race in ktime_get_seconds / timekeeping_advance

write to 0xffffffff86d972c8 of 280 bytes by interrupt on cpu 1:
 timekeeping_advance+0x88e/0xd80 include/linux/string.h:381
 update_wall_time+0x15/0x20 kernel/time/timekeeping.c:2137
 tick_do_update_jiffies64+0x1e5/0x2a0 kernel/time/tick-sched.c:98
 tick_sched_do_timer+0xc7/0xd0 kernel/time/tick-sched.c:142
 tick_sched_timer+0x3f/0xd0 kernel/time/tick-sched.c:1307
 __run_hrtimer kernel/time/hrtimer.c:1517 [inline]
 __hrtimer_run_queues+0x271/0x600 kernel/time/hrtimer.c:1579
 hrtimer_interrupt+0x226/0x490 kernel/time/hrtimer.c:1641
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1119 [inline]
 smp_apic_timer_interrupt+0xd8/0x270 arch/x86/kernel/apic/apic.c:1144
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 arch_local_irq_restore arch/x86/include/asm/paravirt.h:752 [inline]
 kcsan_setup_watchpoint+0x25a/0x440 kernel/kcsan/core.c:530
 ipt_do_table+0x706/0xe70 net/ipv4/netfilter/ip_tables.c:299
 iptable_security_hook+0x44/0x60 net/ipv4/netfilter/iptable_security.c:43
 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
 nf_hook_slow+0x7c/0x160 net/netfilter/core.c:512
 nf_hook include/linux/netfilter.h:262 [inline]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ip_local_deliver+0x1f2/0x220 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
 run_ksoftirqd+0x41/0x60 kernel/softirq.c:603
 smpboot_thread_fn+0x374/0x4a0 kernel/smpboot.c:165
 kthread+0x1cb/0x1f0 kernel/kthread.c:255
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

read to 0xffffffff86d97340 of 8 bytes by task 7835 on cpu 0:
 ktime_get_seconds+0x42/0x60 kernel/time/timekeeping.c:917
 tcp_store_ts_recent net/ipv4/tcp_input.c:3490 [inline]
 tcp_rcv_established+0xe79/0xee0 net/ipv4/tcp_input.c:5674
 tcp_v4_do_rcv+0x396/0x4f0 net/ipv4/tcp_ipv4.c:1619
 sk_backlog_rcv include/net/sock.h:938 [inline]
 __release_sock+0x130/0x1e0 net/core/sock.c:2437
 release_sock+0x5e/0x160 net/core/sock.c:2953
 tcp_recvmsg+0x68f/0x1cc0 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:1895 [inline]
 new_sync_read+0x416/0x450 fs/read_write.c:414
 __vfs_read+0x9e/0xb0 fs/read_write.c:427
 vfs_read fs/read_write.c:461 [inline]
 vfs_read+0x13e/0x2b0 fs/read_write.c:446
 ksys_read+0x16a/0x1a0 fs/read_write.c:587
 __do_sys_read fs/read_write.c:597 [inline]
 __se_sys_read fs/read_write.c:595 [inline]
 __x64_sys_read+0x49/0x60 fs/read_write.c:595
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7835 Comm: syz-fuzzer Not tainted 5.6.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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