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BUG: KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb

read to 0xffff8881033d0a88 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:3181
 skb_xmit_done+0x67/0x1a0 drivers/net/virtio_net.c:770
 vring_interrupt+0x2d7/0x310 drivers/virtio/virtio_ring.c:3335
 __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
 finish_task_switch+0x12b/0x340 kernel/sched/core.c:5434
 context_switch kernel/sched/core.c:5586 [inline]
 __schedule+0x7a9/0xd40 kernel/sched/core.c:7382
 __schedule_loop kernel/sched/core.c:7459 [inline]
 schedule+0x5b/0xa0 kernel/sched/core.c:7474
 do_nanosleep+0xc5/0x390 kernel/time/hrtimer.c:2441
 hrtimer_nanosleep+0xf2/0x290 kernel/time/hrtimer.c:2487
 common_nsleep+0x62/0x80 kernel/time/posix-timers.c:1373
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1419 [inline]
 __se_sys_clock_nanosleep+0x223/0x260 kernel/time/posix-timers.c:1396
 __x64_sys_clock_nanosleep+0x55/0x70 kernel/time/posix-timers.c:1396
 x64_sys_call+0x244d/0x2550 arch/x86/include/generated/asm/syscalls_64.h:231
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff8881033d0a88 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:3181
 start_xmit+0x104/0x1bf0 drivers/net/virtio_net.c:3371
 __netdev_start_xmit include/linux/netdevice.h:5455 [inline]
 netdev_start_xmit include/linux/netdevice.h:5464 [inline]
 xmit_one net/core/dev.c:4068 [inline]
 dev_hard_start_xmit+0x10c/0x380 net/core/dev.c:4084
 sch_direct_xmit+0x19e/0x350 net/sched/sch_generic.c:380
 __dev_xmit_skb net/core/dev.c:4405 [inline]
 __dev_queue_xmit+0xda5/0x1ec0 net/core/dev.c:5044
 dev_queue_xmit include/linux/netdevice.h:3483 [inline]
 neigh_hh_output include/net/neighbour.h:538 [inline]
 neigh_output include/net/neighbour.h:552 [inline]
 ip_finish_output2+0x807/0x8e0 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:314 [inline]
 ip_output+0xbd/0x1c0 net/ipv4/ip_output.c:437
 dst_output include/net/dst.h:472 [inline]
 ip_local_out net/ipv4/ip_output.c:131 [inline]
 __ip_queue_xmit+0xb7c/0xbb0 net/ipv4/ip_output.c:533
 ip_queue_xmit+0x39/0x50 net/ipv4/ip_output.c:547
 __tcp_transmit_skb+0x1c5e/0x2110 net/ipv4/tcp_output.c:1773
 tcp_transmit_skb net/ipv4/tcp_output.c:1790 [inline]
 tcp_write_xmit+0x17fd/0x3590 net/ipv4/tcp_output.c:3126
 __tcp_push_pending_frames+0x6d/0x1b0 net/ipv4/tcp_output.c:3309
 tcp_push_pending_frames include/net/tcp.h:2381 [inline]
 tcp_data_snd_check net/ipv4/tcp_input.c:6158 [inline]
 tcp_rcv_established+0xdc8/0x1330 net/ipv4/tcp_input.c:6643
 tcp_v4_do_rcv+0x3b1/0xa20 net/ipv4/tcp_ipv4.c:1859
 tcp_v4_rcv+0x190e/0x1c50 net/ipv4/tcp_ipv4.c:2253
 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:325 [inline]
 ip_local_deliver+0xe8/0x1e0 net/ipv4/ip_input.c:262
 dst_input include/net/dst.h:482 [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:6477 [inline]
 __netif_receive_skb_list_core+0x4ef/0x520 net/core/dev.c:6523
 __netif_receive_skb_list net/core/dev.c:6575 [inline]
 netif_receive_skb_list_internal+0x471/0x5e0 net/core/dev.c:6666
 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:7034
 virtqueue_napi_complete drivers/net/virtio_net.c:736 [inline]
 virtnet_poll+0x1b41/0x1fe0 drivers/net/virtio_net.c:3048
 __napi_poll+0x61/0x300 net/core/dev.c:7966
 napi_poll net/core/dev.c:8029 [inline]
 net_rx_action+0x456/0x930 net/core/dev.c:8186
 handle_softirqs+0x109/0x310 kernel/softirq.c:669
 __do_softirq kernel/softirq.c:703 [inline]
 invoke_softirq kernel/softirq.c:542 [inline]
 __irq_exit_rcu+0x40/0xf0 kernel/softirq.c:786
 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:273
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:665
 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:123 [inline]
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:211 [inline]
 _raw_spin_unlock_irqrestore+0x1a/0x30 kernel/locking/spinlock.c:221
 spin_unlock_irqrestore include/linux/spinlock.h:425 [inline]
 __uart_port_unlock_irqrestore include/linux/serial_core.h:622 [inline]
 univ8250_console_device_unlock+0x36/0x40 drivers/tty/serial/8250/8250_core.c:420
 nbcon_emit_one kernel/printk/nbcon.c:1165 [inline]
 nbcon_kthread_func+0x5e0/0x6d0 kernel/printk/nbcon.c:1271
 kthread+0x223/0x270 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x0000 -> 0x0001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 30 Comm: pr/ttyS0 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026
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