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BUG: KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb

write to 0xffff888102f4c978 of 2 bytes by interrupt on cpu 1:
 virtqueue_disable_cb_split drivers/virtio/virtio_ring.c:878 [inline]
 virtqueue_disable_cb+0x7a/0x150 drivers/virtio/virtio_ring.c:2569
 skb_xmit_done+0x67/0x1a0 drivers/net/virtio_net.c:800
 vring_interrupt+0x155/0x180 drivers/virtio/virtio_ring.c:2718
 __handle_irq_event_percpu+0x8b/0x4c0 kernel/irq/handle.c:211
 handle_irq_event_percpu kernel/irq/handle.c:248 [inline]
 handle_irq_event+0x64/0xf0 kernel/irq/handle.c:265
 handle_edge_irq+0x154/0x470 kernel/irq/chip.c:855
 generic_handle_irq_desc include/linux/irqdesc.h:172 [inline]
 handle_irq arch/x86/kernel/irq.c:255 [inline]
 call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
 __common_interrupt+0x60/0xb0 arch/x86/kernel/irq.c:326
 common_interrupt+0x7e/0x90 arch/x86/kernel/irq.c:319
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
 kcsan_setup_watchpoint+0x406/0x420 kernel/kcsan/core.c:705
 __copy_msghdr net/socket.c:2481 [inline]
 copy_msghdr_from_user net/socket.c:2525 [inline]
 recvmsg_copy_msghdr net/socket.c:2778 [inline]
 ___sys_recvmsg+0x1db/0x370 net/socket.c:2850
 do_recvmmsg+0x1ef/0x540 net/socket.c:2949
 __sys_recvmmsg net/socket.c:3023 [inline]
 __do_sys_recvmmsg net/socket.c:3046 [inline]
 __se_sys_recvmmsg net/socket.c:3039 [inline]
 __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3039
 x64_sys_call+0x2b75/0x3000 arch/x86/include/generated/asm/syscalls_64.h:300
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xca/0x2b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888102f4c978 of 2 bytes by task 3306 on cpu 0:
 virtqueue_disable_cb_split drivers/virtio/virtio_ring.c:877 [inline]
 virtqueue_disable_cb+0x58/0x150 drivers/virtio/virtio_ring.c:2569
 start_xmit+0x10e/0x17a0 drivers/net/virtio_net.c:3388
 __netdev_start_xmit include/linux/netdevice.h:5273 [inline]
 netdev_start_xmit include/linux/netdevice.h:5282 [inline]
 xmit_one net/core/dev.c:3853 [inline]
 dev_hard_start_xmit+0x125/0x3e0 net/core/dev.c:3869
 sch_direct_xmit+0x192/0x550 net/sched/sch_generic.c:347
 __dev_xmit_skb net/core/dev.c:4169 [inline]
 __dev_queue_xmit+0xcb2/0x1ec0 net/core/dev.c:4783
 dev_queue_xmit include/linux/netdevice.h:3381 [inline]
 neigh_hh_output include/net/neighbour.h:540 [inline]
 neigh_output include/net/neighbour.h:554 [inline]
 ip_finish_output2+0x77f/0x8b0 net/ipv4/ip_output.c:237
 __ip_finish_output net/ipv4/ip_output.c:-1 [inline]
 ip_finish_output+0x114/0x2a0 net/ipv4/ip_output.c:325
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 ip_output+0xbd/0x190 net/ipv4/ip_output.c:438
 dst_output include/net/dst.h:464 [inline]
 ip_local_out net/ipv4/ip_output.c:131 [inline]
 __ip_queue_xmit+0xbbf/0xc00 net/ipv4/ip_output.c:534
 ip_queue_xmit+0x39/0x50 net/ipv4/ip_output.c:548
 __tcp_transmit_skb+0x17fd/0x1c10 net/ipv4/tcp_output.c:1631
 tcp_transmit_skb net/ipv4/tcp_output.c:1649 [inline]
 tcp_write_xmit+0x1477/0x3150 net/ipv4/tcp_output.c:3002
 tcp_push_one+0x7e/0xa0 net/ipv4/tcp_output.c:3199
 tcp_sendmsg_locked+0x1cd0/0x2c00 net/ipv4/tcp.c:1355
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1412
 inet_sendmsg+0x76/0xd0 net/ipv4/af_inet.c:859
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x102/0x180 net/socket.c:742
 sock_write_iter+0x1a7/0x1f0 net/socket.c:1195
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x52a/0x960 fs/read_write.c:686
 ksys_write+0xda/0x1a0 fs/read_write.c:738
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:746
 x64_sys_call+0x2847/0x3000 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xca/0x2b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000 -> 0x0001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3306 Comm: syz-executor Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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