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BUG: KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb

read to 0xffff888103663488 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:3305
 __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
 kcsan_setup_watchpoint+0x42b/0x4a0 kernel/kcsan/core.c:713
 bpf_map_update_value+0x4d6/0x570 kernel/bpf/syscall.c:297
 generic_map_update_batch+0x52d/0x680 kernel/bpf/syscall.c:2106
 bpf_map_do_batch+0x25b/0x380 kernel/bpf/syscall.c:5781
 __sys_bpf+0xa8e/0xc30 kernel/bpf/syscall.c:-1
 __do_sys_bpf kernel/bpf/syscall.c:6486 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6483 [inline]
 __x64_sys_bpf+0x69/0x80 kernel/bpf/syscall.c:6483
 x64_sys_call+0xf26/0x2550 arch/x86/include/generated/asm/syscalls_64.h:322
 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 0xffff888103663488 of 2 bytes by task 24577 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:5429 [inline]
 netdev_start_xmit include/linux/netdevice.h:5438 [inline]
 xmit_one net/core/dev.c:3937 [inline]
 dev_hard_start_xmit+0x10c/0x380 net/core/dev.c:3953
 sch_direct_xmit+0x199/0x580 net/sched/sch_generic.c:372
 __dev_xmit_skb net/core/dev.c:4262 [inline]
 __dev_queue_xmit+0xda5/0x1e90 net/core/dev.c:4884
 dev_queue_xmit include/linux/netdevice.h:3461 [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:314 [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_send_skb+0x11d/0x140 net/ipv4/ip_output.c:1510
 udp_send_skb+0x542/0x7b0 net/ipv4/udp.c:1163
 udp_sendmsg+0x1094/0x14e0 net/ipv4/udp.c:1445
 inet_sendmsg+0xac/0xd0 net/ipv4/af_inet.c:865
 sock_sendmsg_nosec net/socket.c:801 [inline]
 __sock_sendmsg net/socket.c:815 [inline]
 ____sys_sendmsg+0x4e8/0x580 net/socket.c:2713
 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2767
 __sys_sendmmsg+0x185/0x320 net/socket.c:2856
 __do_sys_sendmmsg net/socket.c:2883 [inline]
 __se_sys_sendmmsg net/socket.c:2880 [inline]
 __x64_sys_sendmmsg+0x57/0x70 net/socket.c:2880
 x64_sys_call+0x1fb4/0x2550 arch/x86/include/generated/asm/syscalls_64.h:308
 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

value changed: 0x0000 -> 0x0001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 24577 Comm: syz.9.5064 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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