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BUG: KCSAN: data-race in virtqueue_disable_cb / virtqueue_enable_cb_delayed

write to 0xffff8881293bc4f0 of 2 bytes by interrupt on cpu 0:
 virtqueue_enable_cb_delayed_split drivers/virtio/virtio_ring.c:795 [inline]
 virtqueue_enable_cb_delayed+0x274/0x4a0 drivers/virtio/virtio_ring.c:2007
 start_xmit+0xb0f/0xbe0 drivers/net/virtio_net.c:1565
 __netdev_start_xmit include/linux/netdevice.h:4420 [inline]
 netdev_start_xmit include/linux/netdevice.h:4434 [inline]
 xmit_one net/core/dev.c:3280 [inline]
 dev_hard_start_xmit+0xef/0x430 net/core/dev.c:3296
 sch_direct_xmit+0x2b3/0x870 net/sched/sch_generic.c:313
 __dev_xmit_skb net/core/dev.c:3481 [inline]
 __dev_queue_xmit+0x19c6/0x1b60 net/core/dev.c:3842
 dev_queue_xmit+0x21/0x30 net/core/dev.c:3906
 neigh_hh_output include/net/neighbour.h:500 [inline]
 neigh_output include/net/neighbour.h:509 [inline]
 ip_finish_output2+0x83a/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

read to 0xffff8881293bc4f0 of 2 bytes by interrupt on cpu 1:
 virtqueue_disable_cb_split drivers/virtio/virtio_ring.c:740 [inline]
 virtqueue_disable_cb+0xbc/0x130 drivers/virtio/virtio_ring.c:1926
 virtqueue_napi_schedule+0x52/0x60 drivers/net/virtio_net.c:318
 skb_xmit_done+0xac/0x110 drivers/net/virtio_net.c:346
 vring_interrupt drivers/virtio/virtio_ring.c:2047 [inline]
 vring_interrupt+0x1a1/0x1c0 drivers/virtio/virtio_ring.c:2033
 __handle_irq_event_percpu+0x9a/0x430 kernel/irq/handle.c:149
 handle_irq_event_percpu+0x4b/0xe0 kernel/irq/handle.c:189
 handle_irq_event+0x85/0xca kernel/irq/handle.c:206
 handle_edge_irq+0x1a4/0x4a0 kernel/irq/chip.c:830
 generic_handle_irq_desc include/linux/irqdesc.h:156 [inline]
 do_IRQ+0xa1/0x180 arch/x86/kernel/irq.c:250
 ret_from_intr+0x0/0x19
 check_kcov_mode kernel/kcov.c:68 [inline]
 __sanitizer_cov_trace_pc+0x20/0x50 kernel/kcov.c:102
 tomoyo_domain_quota_is_ok+0x220/0x2b0 security/tomoyo/util.c:1069
 tomoyo_supervisor+0x22b/0xd20 security/tomoyo/common.c:2087

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3888 Comm: udevd 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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