我打算在笔记本电脑上开发一个DPDK Linux 应用程序，但是 DPDK 不支持笔记本电脑的硬件。幸运的是，DPDK支持半虚拟化设备，包括QEMU的virtio-net.
所以我正在尝试配置一个 QEMU 来宾以在设备上运行内核 NIC 接口（KNI）virtio-net-pci。问题是 KNI 示例应用程序不接受virtio-net-pci驱动程序。
QEMU 命令
exec qemu-system-x86_64 -enable-kvm \
-cpu host -smp 2 \
-vga std \
-mem-prealloc -mem-path /dev/hugepages \
-drive file=GentooVM.img,if=virtio \
-netdev user,id=vmnic,hostname=gentoo \
-device virtio-net-pci,netdev=vmnic \
-m 1024M \
-monitor stdio \
-name "Gentoo VM"
在来宾中运行 KNI 示例应用程序
sudo ./examples/kni/build/app/kni -c 0x3 -n 4 -- \
-P -p 0x1 --config="(0,0,1)"
EAL: Detected lcore 0 as core 0 on socket 0
EAL: Detected lcore 1 as core 0 on socket 0
EAL: Support maximum 128 logical core(s) by configuration.
EAL: Detected 2 lcore(s)
EAL: Probing VFIO support...
EAL: IOMMU type 1 (Type 1) is supported
EAL: IOMMU type 8 (No-IOMMU) is not supported
EAL: VFIO support initialized
EAL: Setting up physically contiguous memory...
...
EAL: WARNING: cpu flags constant_tsc=yes nonstop_tsc=no -> using
unreliable clock cycles !
EAL: Master lcore 0 is ready (tid=657d58c0;cpuset=[0])
PMD: rte_igbvf_pmd_init(): >>
EAL: lcore 1 is ready (tid=305ff700;cpuset=[1])
EAL: PCI device 0000:00:03.0 on NUMA socket -1
EAL: probe driver: 1af4:1000 rte_virtio_pmd
EAL: Not managed by a supported kernel driver(0), skipped
PMD: virtio_read_caps(): failed to map pci device!
PMD: vtpci_init(): trying with legacy virtio pci.
Segmentation fault
lspci来宾中的命令输出
...
00:03.0 Ethernet controller: Red Hat, Inc Virtio network device
我注意到pci_scan_one()功能设置dev->kdrv = RTE_KDRV_NONE，而驱动程序被检测为virtio-pci（来自/sys/bus/pci/devices/0000:00:03.0/driver）。
TAP 网络
TAP 网络仍然存在相同的问题。在主机上，我从 Wi-Fi 接口配置了一个网桥，并将其连接到 TAP 接口：
wifi_iface=wlp3s0
br_iface=br0
br_network='172.20.0.1/16'
br_dhcp_range='172.20.0.2,172.20.255.254'
tap_iface=tap0
user=ruslan
ip link add name $br_iface type bridge
ip addr add "$br_network" dev $br_iface
ip link set $br_iface up
dnsmasq --interface=$br_iface --bind-interfaces \
--dhcp-range=$br_dhcp_range
modprobe tun
chmod 0666 /dev/net/tun
ip tuntap add dev $tap_iface mode tap user "$user"
ip link set $tap_iface up promisc on
ip link set $tap_iface master $br_iface
sysctl net.ipv4.ip_forward=1
sysctl net.ipv6.conf.default.forwarding=1
sysctl net.ipv6.conf.all.forwarding=1
iptables -t nat -A POSTROUTING -o $wifi_iface -j MASQUERADE
iptables -A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
iptables -A FORWARD -i $tap_iface -o $wifi_iface -j ACCEPT
QEMU 命令：
sudo qemu-system-x86_64 -enable-kvm \
-cpu host -smp 2 \
-vga std \
-mem-prealloc -mem-path /dev/hugepages \
-drive file=GentooVM.img,if=virtio \
-netdev tap,id=vm1_p1,ifname=tap0,script=no,downscript=no,vhost=on \
-device virtio-net-pci,netdev=vm1_p1,bus=pci.0,addr=0x3,ioeventfd=on \
-m 1024M \
-monitor stdio \
-name "Gentoo VM" \
$@
ifconfig来宾中的输出：
enp0s3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 172.20.196.253 netmask 255.255.0.0 broadcast 172.20.255.255
inet6 fe80::59c1:f175:aeb3:433 prefixlen 64 scopeid 0x20<link>
ether 52:54:00:12:34:56 txqueuelen 1000 (Ethernet)
RX packets 9 bytes 1039 (1.0 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 21 bytes 1802 (1.7 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
以下命令的失败方式与上述“用户”网络的情况相同：
sudo ./examples/kni/build/app/kni -c 0x3 -n 4 -- \
-P -p 0x1 --config="(0,0,1)"
...
EAL: PCI device 0000:00:03.0 on NUMA socket -1
EAL: probe driver: 1af4:1000 rte_virtio_pmd
EAL: Not managed by a supported kernel driver(0), skipped
PMD: virtio_read_caps(): failed to map pci device!
PMD: vtpci_init(): trying with legacy virtio pci.
问题
甚至可以使用设备运行KNI吗？virtio-net-pci
如果不可能，是否有其他选择可以在虚拟化环境中开发DPDK KNI应用程序？