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BUG: KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb

read to 0xffff8881016c6088 of 2 bytes by interrupt on cpu 1:
 virtqueue_disable_cb_split drivers/virtio/virtio_ring.c:1089 [inline]
 virtqueue_disable_cb+0x4c/0x2c0 drivers/virtio/virtio_ring.c:3151
 skb_xmit_done+0x67/0x1a0 drivers/net/virtio_net.c:774
 vring_interrupt+0x2d7/0x310 drivers/virtio/virtio_ring.c:3297
 __handle_irq_event_percpu+0x8b/0x480 kernel/irq/handle.c:209
 handle_irq_event_percpu kernel/irq/handle.c:246 [inline]
 handle_irq_event+0x64/0xf0 kernel/irq/handle.c:263
 handle_edge_irq+0x155/0x440 kernel/irq/chip.c:859
 generic_handle_irq_desc include/linux/irqdesc.h:188 [inline]
 handle_irq arch/x86/kernel/irq.c:209 [inline]
 call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
 __common_interrupt+0x60/0xb0 arch/x86/kernel/irq.c:280
 common_interrupt+0x7e/0x90 arch/x86/kernel/irq.c:273
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:665
 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
 pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
 arch_safe_halt arch/x86/kernel/process.c:767 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:768
 default_idle_call+0x3b/0x60 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x183/0x2d0 kernel/sched/idle.c:355
 cpu_startup_entry+0x24/0x30 kernel/sched/idle.c:454
 start_secondary+0x95/0xa0 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x157

write to 0xffff8881016c6088 of 2 bytes by interrupt on cpu 0:
 virtqueue_disable_cb_split drivers/virtio/virtio_ring.c:1090 [inline]
 virtqueue_disable_cb+0x75/0x2c0 drivers/virtio/virtio_ring.c:3151
 start_xmit+0x107/0x1a80 drivers/net/virtio_net.c:3350
 __netdev_start_xmit include/linux/netdevice.h:5397 [inline]
 netdev_start_xmit include/linux/netdevice.h:5406 [inline]
 xmit_one net/core/dev.c:3889 [inline]
 dev_hard_start_xmit+0x10c/0x380 net/core/dev.c:3905
 sch_direct_xmit+0x199/0x580 net/sched/sch_generic.c:372
 __dev_xmit_skb net/core/dev.c:4214 [inline]
 __dev_queue_xmit+0xda4/0x1e90 net/core/dev.c:4836
 dev_queue_xmit include/linux/netdevice.h:3448 [inline]
 neigh_hh_output include/net/neighbour.h:544 [inline]
 neigh_output include/net/neighbour.h:558 [inline]
 ip_finish_output2+0x752/0x8a0 net/ipv4/ip_output.c:236
 __ip_finish_output net/ipv4/ip_output.c:-1 [inline]
 ip_finish_output+0x112/0x290 net/ipv4/ip_output.c:324
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 ip_output+0xbd/0x1c0 net/ipv4/ip_output.c:437
 dst_output include/net/dst.h:471 [inline]
 ip_local_out net/ipv4/ip_output.c:131 [inline]
 __ip_queue_xmit+0xb4c/0xb80 net/ipv4/ip_output.c:533
 ip_queue_xmit+0x39/0x50 net/ipv4/ip_output.c:547
 __tcp_transmit_skb+0x1c4f/0x20f0 net/ipv4/tcp_output.c:1717
 tcp_transmit_skb net/ipv4/tcp_output.c:1734 [inline]
 tcp_write_xmit+0x17f7/0x3630 net/ipv4/tcp_output.c:3062
 __tcp_push_pending_frames+0x6d/0x1b0 net/ipv4/tcp_output.c:3245
 tcp_push_pending_frames include/net/tcp.h:2337 [inline]
 tcp_data_snd_check net/ipv4/tcp_input.c:6108 [inline]
 tcp_rcv_established+0xdbf/0x1340 net/ipv4/tcp_input.c:6591
 tcp_v4_do_rcv+0x3b1/0xa20 net/ipv4/tcp_ipv4.c:1854
 tcp_v4_rcv+0x190e/0x1c50 net/ipv4/tcp_ipv4.c:2248
 ip_protocol_deliver_rcu+0x38c/0x7a0 net/ipv4/ip_input.c:207
 ip_local_deliver_finish+0x1f0/0x2e0 net/ipv4/ip_input.c:241
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ip_local_deliver+0xe8/0x1e0 net/ipv4/ip_input.c:262
 dst_input include/net/dst.h:481 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:623 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:675 [inline]
 ip_sublist_rcv+0x587/0x680 net/ipv4/ip_input.c:683
 ip_list_rcv+0x261/0x290 net/ipv4/ip_input.c:717
 __netif_receive_skb_list_ptype net/core/dev.c:6256 [inline]
 __netif_receive_skb_list_core+0x4ef/0x520 net/core/dev.c:6302
 __netif_receive_skb_list net/core/dev.c:6354 [inline]
 netif_receive_skb_list_internal+0x471/0x5e0 net/core/dev.c:6445
 gro_normal_list include/net/gro.h:523 [inline]
 gro_flush_normal include/net/gro.h:531 [inline]
 napi_complete_done+0x19c/0x3f0 net/core/dev.c:6813
 virtqueue_napi_complete drivers/net/virtio_net.c:740 [inline]
 virtnet_poll+0x1b16/0x1fb0 drivers/net/virtio_net.c:3027
 __napi_poll+0x61/0x300 net/core/dev.c:7735
 napi_poll net/core/dev.c:7798 [inline]
 net_rx_action+0x456/0x930 net/core/dev.c:7955
 handle_softirqs+0xb9/0x280 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x42/0xd0 kernel/softirq.c:735
 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:273
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:665
 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
 pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
 arch_safe_halt arch/x86/kernel/process.c:767 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:768
 default_idle_call+0x3b/0x60 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x183/0x2d0 kernel/sched/idle.c:355
 cpu_startup_entry+0x24/0x30 kernel/sched/idle.c:454
 rest_init+0xee/0xf0 init/main.c:717
 start_kernel+0x49f/0x4d0 init/main.c:1175
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0xfc/0x100 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x157

value changed: 0x0000 -> 0x0001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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