syzbot

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BUG: KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb

read to 0xffff88810358d588 of 2 bytes by interrupt on cpu 1:
 virtqueue_disable_cb_split drivers/virtio/virtio_ring.c:1046 [inline]
 virtqueue_disable_cb+0x4c/0x2c0 drivers/virtio/virtio_ring.c:3108
 skb_xmit_done+0x67/0x1a0 drivers/net/virtio_net.c:783
 vring_interrupt+0x2d7/0x310 drivers/virtio/virtio_ring.c:3254
 __handle_irq_event_percpu+0x9c/0x4d0 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+0x154/0x470 kernel/irq/chip.c:855
 generic_handle_irq_desc include/linux/irqdesc.h:186 [inline]
 handle_irq arch/x86/kernel/irq.c:262 [inline]
 call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
 __common_interrupt+0x60/0xb0 arch/x86/kernel/irq.c:333
 common_interrupt+0x7e/0x90 arch/x86/kernel/irq.c:326
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
 should_flush_tlb+0x16/0x60 arch/x86/mm/tlb.c:1299
 smp_call_function_many_cond+0x2c1/0xc30 kernel/smp.c:821
 on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1043
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:57 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline]
 flush_tlb_mm_range+0x1f9/0x560 arch/x86/mm/tlb.c:1472
 tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
 tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:505 [inline]
 tlb_flush_mmu+0x158/0x6d0 mm/mmu_gather.c:404
 tlb_finish_mmu+0x8d/0x110 mm/mmu_gather.c:530
 unmap_region+0x181/0x1b0 mm/vma.c:488
 vms_clear_ptes mm/vma.c:1284 [inline]
 vms_complete_munmap_vmas+0x2d7/0x5e0 mm/vma.c:1326
 do_vmi_align_munmap+0x3c3/0x400 mm/vma.c:1585
 do_vmi_munmap+0x1da/0x220 mm/vma.c:1633
 __vm_munmap+0x1a8/0x290 mm/vma.c:3254
 __do_sys_munmap mm/mmap.c:1078 [inline]
 __se_sys_munmap mm/mmap.c:1075 [inline]
 __x64_sys_munmap+0x36/0x50 mm/mmap.c:1075
 x64_sys_call+0x9c0/0x3020 arch/x86/include/generated/asm/syscalls_64.h:12
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff88810358d588 of 2 bytes by task 3299 on cpu 0:
 virtqueue_disable_cb_split drivers/virtio/virtio_ring.c:1047 [inline]
 virtqueue_disable_cb+0x75/0x2c0 drivers/virtio/virtio_ring.c:3108
 start_xmit+0x102/0x17c0 drivers/net/virtio_net.c:3331
 __netdev_start_xmit include/linux/netdevice.h:5275 [inline]
 netdev_start_xmit include/linux/netdevice.h:5284 [inline]
 xmit_one net/core/dev.c:3871 [inline]
 dev_hard_start_xmit+0x136/0x3f0 net/core/dev.c:3887
 sch_direct_xmit+0x192/0x550 net/sched/sch_generic.c:347
 __dev_xmit_skb net/core/dev.c:4186 [inline]
 __dev_queue_xmit+0xca9/0x1f40 net/core/dev.c:4802
 dev_queue_xmit include/linux/netdevice.h:3384 [inline]
 neigh_hh_output include/net/neighbour.h:540 [inline]
 neigh_output include/net/neighbour.h:554 [inline]
 ip_finish_output2+0x705/0x8c0 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/0x1c0 net/ipv4/ip_output.c:438
 dst_output include/net/dst.h:470 [inline]
 ip_local_out net/ipv4/ip_output.c:131 [inline]
 __ip_queue_xmit+0xbb0/0xbf0 net/ipv4/ip_output.c:534
 ip_queue_xmit+0x39/0x50 net/ipv4/ip_output.c:548
 __tcp_transmit_skb+0x1af2/0x1f10 net/ipv4/tcp_output.c:1693
 tcp_transmit_skb net/ipv4/tcp_output.c:1711 [inline]
 tcp_write_xmit+0x1597/0x3640 net/ipv4/tcp_output.c:3064
 tcp_push_one+0x7e/0xa0 net/ipv4/tcp_output.c:3261
 tcp_sendmsg_locked+0x1eae/0x2de0 net/ipv4/tcp.c:1407
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1464
 inet_sendmsg+0x76/0xd0 net/ipv4/af_inet.c:859
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 sock_write_iter+0x2e0/0x360 net/socket.c:1195
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x5a6/0x9f0 fs/read_write.c:688
 ksys_write+0xdc/0x1a0 fs/read_write.c:740
 __do_sys_write fs/read_write.c:751 [inline]
 __se_sys_write fs/read_write.c:748 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:748
 x64_sys_call+0x27e1/0x3020 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 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: 3299 Comm: syz-executor Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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