================================================================== BUG: KCSAN: data-race in virtqueue_disable_cb / virtqueue_get_buf_ctx read to 0xffff8881293c5c70 of 2 bytes by interrupt on cpu 1: virtqueue_get_buf_ctx_split drivers/virtio/virtio_ring.c:725 [inline] virtqueue_get_buf_ctx+0x4da/0x5c0 drivers/virtio/virtio_ring.c:1900 virtqueue_get_buf+0x29/0x40 drivers/virtio/virtio_ring.c:1906 free_old_xmit_skbs+0x9e/0x170 drivers/net/virtio_net.c:1359 start_xmit+0xd3/0xbe0 drivers/net/virtio_net.c:1562 __netdev_start_xmit include/linux/netdevice.h:4413 [inline] netdev_start_xmit include/linux/netdevice.h:4427 [inline] xmit_one net/core/dev.c:3199 [inline] dev_hard_start_xmit+0xef/0x430 net/core/dev.c:3215 sch_direct_xmit+0x2b3/0x900 net/sched/sch_generic.c:313 __dev_xmit_skb net/core/dev.c:3400 [inline] __dev_queue_xmit+0x19a3/0x1b40 net/core/dev.c:3761 dev_queue_xmit+0x21/0x30 net/core/dev.c:3825 neigh_hh_output include/net/neighbour.h:500 [inline] neigh_output include/net/neighbour.h:509 [inline] ip_finish_output2+0x836/0xe40 net/ipv4/ip_output.c:228 __ip_finish_output net/ipv4/ip_output.c:308 [inline] __ip_finish_output+0x23a/0x490 net/ipv4/ip_output.c:290 ip_finish_output+0x41/0x160 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip_output+0xdf/0x210 net/ipv4/ip_output.c:432 dst_output include/net/dst.h:436 [inline] ip_local_out+0x74/0x90 net/ipv4/ip_output.c:125 __ip_queue_xmit+0x3a8/0xa40 net/ipv4/ip_output.c:532 ip_queue_xmit+0x45/0x60 include/net/ip.h:237 __tcp_transmit_skb+0xe81/0x1d60 net/ipv4/tcp_output.c:1169 tcp_transmit_skb net/ipv4/tcp_output.c:1185 [inline] tcp_write_xmit+0xa54/0x3120 net/ipv4/tcp_output.c:2440 __tcp_push_pending_frames+0x7b/0x1d0 net/ipv4/tcp_output.c:2616 tcp_push_pending_frames include/net/tcp.h:1810 [inline] tcp_data_snd_check net/ipv4/tcp_input.c:5217 [inline] tcp_rcv_established+0x56a/0xf50 net/ipv4/tcp_input.c:5709 tcp_v4_do_rcv+0x3b5/0x520 net/ipv4/tcp_ipv4.c:1564 tcp_v4_rcv+0x19ec/0x1bd0 net/ipv4/tcp_ipv4.c:1945 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:4929 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5043 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5133 napi_skb_finish net/core/dev.c:5596 [inline] napi_gro_receive+0x28f/0x330 net/core/dev.c:5629 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061 virtnet_receive drivers/net/virtio_net.c:1323 [inline] virtnet_poll+0x436/0x7d0 drivers/net/virtio_net.c:1428 napi_poll net/core/dev.c:6311 [inline] net_rx_action+0x3ae/0xa90 net/core/dev.c:6379 __do_softirq+0x115/0x33f kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0xbb/0xe0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] do_IRQ+0x81/0x130 arch/x86/kernel/irq.c:263 ret_from_intr+0x0/0x19 arch_local_irq_restore arch/x86/include/asm/paravirt.h:756 [inline] kcsan_setup_watchpoint+0x1d4/0x460 kernel/kcsan/core.c:436 check_access kernel/kcsan/core.c:466 [inline] __tsan_read8 kernel/kcsan/core.c:596 [inline] __tsan_read8+0xc6/0x100 kernel/kcsan/core.c:596 vm_normal_page+0xc1/0x220 mm/memory.c:616 copy_one_pte mm/memory.c:770 [inline] copy_pte_range mm/memory.c:823 [inline] copy_pmd_range mm/memory.c:874 [inline] copy_pud_range mm/memory.c:908 [inline] copy_p4d_range mm/memory.c:930 [inline] copy_page_range+0xc63/0x1a80 mm/memory.c:992 dup_mmap kernel/fork.c:601 [inline] dup_mm+0x74a/0xba0 kernel/fork.c:1361 copy_mm kernel/fork.c:1417 [inline] copy_process+0x36f3/0x3b50 kernel/fork.c:2012 _do_fork+0xfe/0x6e0 kernel/fork.c:2366 __do_sys_clone kernel/fork.c:2521 [inline] __se_sys_clone kernel/fork.c:2502 [inline] __x64_sys_clone+0x12b/0x160 kernel/fork.c:2502 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 write to 0xffff8881293c5c70 of 2 bytes by interrupt on cpu 0: virtqueue_disable_cb_split drivers/virtio/virtio_ring.c:741 [inline] virtqueue_disable_cb+0xe9/0x130 drivers/virtio/virtio_ring.c:1925 skb_xmit_done+0x6a/0x110 drivers/net/virtio_net.c:343 vring_interrupt drivers/virtio/virtio_ring.c:2046 [inline] vring_interrupt+0x1a1/0x1c0 drivers/virtio/virtio_ring.c:2032 __handle_irq_event_percpu+0x9a/0x430 kernel/irq/handle.c:149 handle_irq_event_percpu+0x4b/0xe0 kernel/irq/handle.c:189 handle_irq_event+0x85/0xca kernel/irq/handle.c:206 handle_edge_irq+0x1a4/0x4a0 kernel/irq/chip.c:830 generic_handle_irq_desc include/linux/irqdesc.h:156 [inline] do_IRQ+0x7c/0x130 arch/x86/kernel/irq.c:250 ret_from_intr+0x0/0x19 do_select+0x8/0x1020 fs/select.c:477 core_sys_select+0x381/0x550 fs/select.c:677 do_pselect.constprop.0+0x11d/0x160 fs/select.c:759 __do_sys_pselect6 fs/select.c:784 [inline] __se_sys_pselect6 fs/select.c:769 [inline] __x64_sys_pselect6+0x12e/0x170 fs/select.c:769 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 7717 Comm: syz-fuzzer Not tainted 5.4.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================