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BUG: KCSAN: data-race in virtqueue_disable_cb / vring_interrupt

write to 0xffff88810291fe8a of 1 bytes by interrupt on cpu 1:
 vring_interrupt+0x132/0x180 drivers/virtio/virtio_ring.c:2148
 __handle_irq_event_percpu+0x93/0x3f0 kernel/irq/handle.c:156
 handle_irq_event_percpu kernel/irq/handle.c:196 [inline]
 handle_irq_event+0xb6/0x170 kernel/irq/handle.c:213
 handle_edge_irq+0x17e/0x600 kernel/irq/chip.c:819
 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
 handle_irq arch/x86/kernel/irq.c:231 [inline]
 __common_interrupt+0x38/0xb0 arch/x86/kernel/irq.c:250
 common_interrupt+0x39/0x90 arch/x86/kernel/irq.c:240
 asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629

read to 0xffff88810291fe8a of 1 bytes by interrupt on cpu 0:
 virtqueue_disable_cb+0x19/0x160 drivers/virtio/virtio_ring.c:2012
 start_xmit+0xc0/0xb10 drivers/net/virtio_net.c:1699
 __netdev_start_xmit include/linux/netdevice.h:4944 [inline]
 netdev_start_xmit include/linux/netdevice.h:4958 [inline]
 xmit_one+0xf9/0x270 net/core/dev.c:3658
 dev_hard_start_xmit+0x72/0x120 net/core/dev.c:3674
 sch_direct_xmit+0x1a8/0x5c0 net/sched/sch_generic.c:342
 __dev_xmit_skb net/core/dev.c:3874 [inline]
 __dev_queue_xmit+0xe9a/0x1c10 net/core/dev.c:4241
 dev_queue_xmit+0x13/0x20 net/core/dev.c:4306
 neigh_hh_output include/net/neighbour.h:499 [inline]
 neigh_output include/net/neighbour.h:508 [inline]
 ip_finish_output2+0xa93/0xb10 net/ipv4/ip_output.c:230
 __ip_finish_output net/ipv4/ip_output.c:252 [inline]
 ip_finish_output+0x2fa/0x490 net/ipv4/ip_output.c:318
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0xf3/0x1a0 net/ipv4/ip_output.c:432
 dst_output include/net/dst.h:448 [inline]
 ip_local_out+0x164/0x220 net/ipv4/ip_output.c:126
 __ip_queue_xmit+0x97f/0x9a0 net/ipv4/ip_output.c:533
 ip_queue_xmit+0x34/0x40 net/ipv4/ip_output.c:547
 __tcp_transmit_skb+0x140a/0x19e0 net/ipv4/tcp_output.c:1405
 __tcp_send_ack+0x20a/0x300 net/ipv4/tcp_output.c:3970
 tcp_send_ack+0x23/0x30 net/ipv4/tcp_output.c:3976
 __tcp_ack_snd_check+0x2d8/0x510 net/ipv4/tcp_input.c:5421
 tcp_rcv_established+0x119b/0x1320 net/ipv4/tcp_input.c:5855
 tcp_v4_do_rcv+0x261/0x4f0 net/ipv4/tcp_ipv4.c:1694
 tcp_v4_rcv+0x217c/0x2480 net/ipv4/tcp_ipv4.c:2087
 ip_protocol_deliver_rcu+0x20e/0x410 net/ipv4/ip_input.c:204
 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ip_local_deliver+0x1d1/0x290 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:458 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:551 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:601 [inline]
 ip_sublist_rcv+0x3e4/0x4a0 net/ipv4/ip_input.c:609
 ip_list_rcv+0x262/0x290 net/ipv4/ip_input.c:644
 __netif_receive_skb_list_ptype net/core/dev.c:5529 [inline]
 __netif_receive_skb_list_core+0x34b/0x450 net/core/dev.c:5577
 __netif_receive_skb_list+0x262/0x2e0 net/core/dev.c:5629
 netif_receive_skb_list_internal+0xd5/0x330 net/core/dev.c:5739
 gro_normal_list net/core/dev.c:5893 [inline]
 napi_complete_done+0x1b2/0x3b0 net/core/dev.c:6599
 virtqueue_napi_complete drivers/net/virtio_net.c:337 [inline]
 virtnet_poll+0x6a3/0x9b0 drivers/net/virtio_net.c:1546
 __napi_poll+0x65/0x3a0 net/core/dev.c:7019
 napi_poll net/core/dev.c:7086 [inline]
 net_rx_action+0x29f/0x680 net/core/dev.c:7173
 __do_softirq+0x12c/0x26e kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x9a/0xb0 kernel/softirq.c:636
 common_interrupt+0x3e/0x90 arch/x86/kernel/irq.c:240
 asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1757 Comm: syz-fuzzer Not tainted 5.14.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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