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BUG: KCSAN: data-race in __neigh_event_send / neigh_resolve_output

write to 0xffff8880a604d285 of 1 bytes by interrupt on cpu 0:
 __neigh_event_send+0x186/0x970 net/core/neighbour.c:1128
 neigh_event_send include/net/neighbour.h:445 [inline]
 neigh_resolve_output+0x353/0x480 net/core/neighbour.c:1474
 neigh_output include/net/neighbour.h:511 [inline]
 ip_finish_output2+0x4af/0xe40 net/ipv4/ip_output.c:228
 __ip_finish_output net/ipv4/ip_output.c:308 [inline]
 __ip_finish_output+0x23a/0x490 net/ipv4/ip_output.c:290
 ip_finish_output+0x41/0x160 net/ipv4/ip_output.c:318
 NF_HOOK_COND include/linux/netfilter.h:294 [inline]
 ip_output+0xdf/0x210 net/ipv4/ip_output.c:432
 dst_output include/net/dst.h:436 [inline]
 ip_local_out+0x74/0x90 net/ipv4/ip_output.c:125
 __ip_queue_xmit+0x3a8/0xa40 net/ipv4/ip_output.c:532
 ip_queue_xmit+0x45/0x60 include/net/ip.h:237
 __tcp_transmit_skb+0xe81/0x1d60 net/ipv4/tcp_output.c:1169
 tcp_transmit_skb net/ipv4/tcp_output.c:1185 [inline]
 tcp_xmit_probe_skb+0x19b/0x1d0 net/ipv4/tcp_output.c:3735
 tcp_write_wakeup+0x12e/0x3b0 net/ipv4/tcp_output.c:3788
 tcp_send_probe0+0x3a/0x286 net/ipv4/tcp_output.c:3803
 tcp_probe_timer net/ipv4/tcp_timer.c:381 [inline]
 tcp_write_timer_handler+0x48e/0x510 net/ipv4/tcp_timer.c:602

read to 0xffff8880a604d285 of 1 bytes by interrupt on cpu 1:
 neigh_event_send include/net/neighbour.h:444 [inline]
 neigh_resolve_output+0x91/0x480 net/core/neighbour.c:1474
 neigh_output include/net/neighbour.h:511 [inline]
 ip_finish_output2+0x4af/0xe40 net/ipv4/ip_output.c:228
 __ip_finish_output net/ipv4/ip_output.c:308 [inline]
 __ip_finish_output+0x23a/0x490 net/ipv4/ip_output.c:290
 ip_finish_output+0x41/0x160 net/ipv4/ip_output.c:318
 NF_HOOK_COND include/linux/netfilter.h:294 [inline]
 ip_output+0xdf/0x210 net/ipv4/ip_output.c:432
 dst_output include/net/dst.h:436 [inline]
 ip_local_out+0x74/0x90 net/ipv4/ip_output.c:125
 __ip_queue_xmit+0x3a8/0xa40 net/ipv4/ip_output.c:532
 ip_queue_xmit+0x45/0x60 include/net/ip.h:237
 __tcp_transmit_skb+0xe81/0x1d60 net/ipv4/tcp_output.c:1169
 tcp_transmit_skb net/ipv4/tcp_output.c:1185 [inline]
 tcp_xmit_probe_skb+0x19b/0x1d0 net/ipv4/tcp_output.c:3735
 tcp_write_wakeup+0x12e/0x3b0 net/ipv4/tcp_output.c:3788
 tcp_send_probe0+0x3a/0x286 net/ipv4/tcp_output.c:3803
 tcp_probe_timer net/ipv4/tcp_timer.c:381 [inline]
 tcp_write_timer_handler+0x48e/0x510 net/ipv4/tcp_timer.c:602

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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