================================================================== BUG: KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb write to 0xffff888103638788 of 2 bytes by interrupt on cpu 1: virtqueue_disable_cb_split drivers/virtio/virtio_ring.c:1047 [inline] virtqueue_disable_cb+0x75/0x2c0 drivers/virtio/virtio_ring.c:3108 start_xmit+0x107/0x1ab0 drivers/net/virtio_net.c:3333 __netdev_start_xmit include/linux/netdevice.h:5325 [inline] netdev_start_xmit include/linux/netdevice.h:5334 [inline] xmit_one net/core/dev.c:3888 [inline] dev_hard_start_xmit+0x136/0x3f0 net/core/dev.c:3904 sch_direct_xmit+0x192/0x550 net/sched/sch_generic.c:347 __dev_xmit_skb net/core/dev.c:4203 [inline] __dev_queue_xmit+0xca9/0x1f20 net/core/dev.c:4819 dev_queue_xmit include/linux/netdevice.h:3385 [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+0x112/0x290 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+0xb68/0xba0 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_pending_frames+0x6d/0x1b0 net/ipv4/tcp_output.c:3247 tcp_push_pending_frames include/net/tcp.h:2285 [inline] tcp_data_snd_check net/ipv4/tcp_input.c:6127 [inline] tcp_rcv_established+0xda2/0x12f0 net/ipv4/tcp_input.c:6610 tcp_v4_do_rcv+0x91d/0xa30 net/ipv4/tcp_ipv4.c:1884 tcp_v4_rcv+0x19f8/0x1db0 net/ipv4/tcp_ipv4.c:2319 ip_protocol_deliver_rcu+0x395/0x790 net/ipv4/ip_input.c:207 ip_local_deliver_finish+0x1fc/0x2f0 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:480 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:584 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:636 [inline] ip_sublist_rcv+0x5a4/0x6a0 net/ipv4/ip_input.c:644 ip_list_rcv+0x261/0x290 net/ipv4/ip_input.c:678 __netif_receive_skb_list_ptype net/core/dev.c:6224 [inline] __netif_receive_skb_list_core+0x4dc/0x500 net/core/dev.c:6271 __netif_receive_skb_list net/core/dev.c:6323 [inline] netif_receive_skb_list_internal+0x47d/0x5f0 net/core/dev.c:6414 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:6782 virtqueue_napi_complete drivers/net/virtio_net.c:747 [inline] virtnet_poll+0x1bb1/0x2040 drivers/net/virtio_net.c:3089 __napi_poll+0x61/0x330 net/core/dev.c:7709 napi_poll net/core/dev.c:7772 [inline] net_rx_action+0x452/0x930 net/core/dev.c:7929 handle_softirqs+0xb9/0x2a0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x39/0xc0 kernel/softirq.c:723 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:326 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688 kcsan_setup_watchpoint+0x404/0x410 kernel/kcsan/core.c:705 __copy_msghdr net/socket.c:2475 [inline] copy_msghdr_from_user net/socket.c:2525 [inline] recvmsg_copy_msghdr net/socket.c:2778 [inline] ___sys_recvmsg+0x187/0x3b0 net/socket.c:2850 do_recvmmsg+0x1ef/0x560 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+0x80f/0x3020 arch/x86/include/generated/asm/syscalls_64.h:300 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 read to 0xffff888103638788 of 2 bytes by interrupt on cpu 0: 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:781 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 kcsan_setup_watchpoint+0x404/0x410 kernel/kcsan/core.c:705 get_futex_key+0xa8/0xbe0 kernel/futex/core.c:568 futex_wake+0x84/0x380 kernel/futex/waitwake.c:165 do_futex+0x323/0x380 kernel/futex/syscalls.c:135 mm_release+0xa1/0x190 kernel/fork.c:1479 exit_mm_release+0x25/0x30 kernel/fork.c:1496 exit_mm+0x37/0x180 kernel/exit.c:554 do_exit+0x442/0x1600 kernel/exit.c:964 do_group_exit+0xfe/0x140 kernel/exit.c:1118 get_signal+0xe54/0xf60 kernel/signal.c:3034 arch_do_signal_or_restart+0x96/0x450 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x6a/0x6f0 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x249/0x370 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x0000 -> 0x0001 Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 7037 Comm: syz.9.939 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 ==================================================================