1. 目前遇到一个环境 虚拟机使用 dpdk 后，无法收发包
问题表现：
虚拟机内部 ping 网关 ping 不通，
ovs-vsctl list interface 看到的 dpdk vhost unix sock 对应的 port 基于 ovs-tcpdump 根本就抓不到包，但是 ovs 服务正常，流表正常。
在 虚拟机内部 保持 ping 网关，但是 ping 不通， 而且 ifconfig 根本就没有 错误计数，错误计数始终为 0
目前使用的镜像是： docker pull 599230270/kube-ovn:v1.12.0-dpdk-no-avx512
该镜像是 Fedora 构建的， Fedora 本身是不支持 avx512 的。
由于 kubevirt 也是 红帽的，基于这个原因，不使用 avx512 估计是为了避坑。
Fedora 是商业化的Red Hat Enterprise Linux发行版的上游源码。
该镜像是在 Fedora 支持多队列网卡的虚拟机中构建的，而我的宿主机是 基于 centos 的。 本身也是比较接近的。
centos fedora redhat 三者之间的关系：
RedHat Enterprise 发行之前：
RedHat Enterprise 发行后， 4.0 版本开始：
CentOS 停止，centos stream 发起之后：
fedora 作为 centos stream 的上游，编译出来的东西， centos 应该也是能用的。
1.1 目前存在两个环境 kube-ovn ovs-dpdk 版本是一致的，但是有一个环境不通。
通过对比 xml 发现 是没有配置共享内存，导致 dpdk vhost 基于 共享内存转发包，导致网络不通。
在定位中 发现 dpdk vhost unix sock 文件 和 linux 的 内核态 unix sock 存在不同。基于内核态的编码抓包是抓不到 dpdk vhost unix sock io 的数据流的
# 好的 虚拟机的 xml
<domain type='kvm' id='1'>
<name>default_vm-fedora-dpdk-1</name>
<uuid>83d8713e-a51a-5d06-ab4e-f11a670b5e98</uuid>
<metadata>
<kubevirt xmlns="http://kubevirt.io">
<uid/>
</kubevirt>
</metadata>
<memory unit='KiB'>4194304</memory>
<currentMemory unit='KiB'>4194304</currentMemory>
<memoryBacking>
<hugepages/>
<source type='memfd'/> # 这里有配置共享内存
</memoryBacking>
<vcpu placement='static'>4</vcpu>
<iothreads>1</iothreads>
<resource>
<partition>/machine</partition>
</resource>
<sysinfo type='smbios'>
<system>
<entry name='manufacturer'>KubeVirt</entry>
<entry name='product'>None</entry>
<entry name='uuid'>83d8713e-a51a-5d06-ab4e-f11a670b5e98</entry>
<entry name='family'>KubeVirt</entry>
</system>
</sysinfo>
<os>
<type arch='x86_64' machine='pc-q35-rhel9.2.0'>hvm</type>
<boot dev='hd'/>
<smbios mode='sysinfo'/>
</os>
<features>
<acpi/>
</features>
<cpu mode='custom' match='exact' check='full'>
<model fallback='forbid'>Broadwell</model>
<vendor>Intel</vendor>
<topology sockets='1' dies='1' cores='4' threads='1'/>
<feature policy='require' name='vme'/>
<feature policy='require' name='ss'/>
<feature policy='require' name='vmx'/>
<feature policy='require' name='f16c'/>
<feature policy='require' name='rdrand'/>
<feature policy='require' name='hypervisor'/>
<feature policy='require' name='arat'/>
<feature policy='require' name='tsc_adjust'/>
<feature policy='require' name='umip'/>
<feature policy='require' name='arch-capabilities'/>
<feature policy='require' name='xsaveopt'/>
<feature policy='require' name='pdpe1gb'/>
<feature policy='require' name='abm'/>
<feature policy='require' name='skip-l1dfl-vmentry'/>
<feature policy='require' name='pschange-mc-no'/>
<numa>
<cell id='0' cpus='0-3' memory='4194304' unit='KiB'/>
</numa>
</cpu>
<clock offset='utc'/>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>destroy</on_crash>
<devices>
<emulator>/usr/libexec/qemu-kvm</emulator>
<disk type='file' device='disk' model='virtio-non-transitional'>
<driver name='qemu' type='qcow2' cache='none' error_policy='stop' discard='unmap'/>
<source file='/var/run/kubevirt-ephemeral-disks/disk-data/containerdisk/disk.qcow2' index='1'/>
<backingStore type='file' index='2'>
<format type='qcow2'/>
<source file='/var/run/kubevirt/container-disks/disk_0.img'/>
</backingStore>
<target dev='vda' bus='virtio'/>
<alias name='ua-containerdisk'/>
<address type='pci' domain='0x0000' bus='0x07' slot='0x00' function='0x0'/>
</disk>
<controller type='usb' index='0' model='none'>
<alias name='usb'/>
</controller>
<controller type='scsi' index='0' model='virtio-non-transitional'>
<alias name='scsi0'/>
<address type='pci' domain='0x0000' bus='0x05' slot='0x00' function='0x0'/>
</controller>
<controller type='virtio-serial' index='0' model='virtio-non-transitional'>
<alias name='virtio-serial0'/>
<address type='pci' domain='0x0000' bus='0x06' slot='0x00' function='0x0'/>
</controller>
<controller type='sata' index='0'>
<alias name='ide'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x1f' function='0x2'/>
</controller>
<controller type='pci' index='0' model='pcie-root'>
<alias name='pcie.0'/>
</controller>
<controller type='pci' index='1' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='1' port='0x10'/>
<alias name='pci.1'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0' multifunction='on'/>
</controller>
<controller type='pci' index='2' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='2' port='0x11'/>
<alias name='pci.2'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x1'/>
</controller>
<controller type='pci' index='3' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='3' port='0x12'/>
<alias name='pci.3'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x2'/>
</controller>
<controller type='pci' index='4' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='4' port='0x13'/>
<alias name='pci.4'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x3'/>
</controller>
<controller type='pci' index='5' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='5' port='0x14'/>
<alias name='pci.5'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x4'/>
</controller>
<controller type='pci' index='6' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='6' port='0x15'/>
<alias name='pci.6'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x5'/>
</controller>
<controller type='pci' index='7' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='7' port='0x16'/>
<alias name='pci.7'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x6'/>
</controller>
<controller type='pci' index='8' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='8' port='0x17'/>
<alias name='pci.8'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x7'/>
</controller>
<controller type='pci' index='9' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='9' port='0x18'/>
<alias name='pci.9'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
</controller>
<interface type='vhostuser'>
<mac address='00:00:00:2c:ac:b6'/>
<source type='unix' path='/var/run/vm/dpdk/pod6c270ef2f25' mode='server'/>
<model type='virtio-non-transitional'/>
<driver name='vhost' queues='4' rx_queue_size='1024' tx_queue_size='1024'/>
<alias name='ua-net1'/>
<address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/>
</interface>
<serial type='unix'>
<source mode='bind' path='/var/run/kubevirt-private/5950bc0a-fde5-4b96-9958-e7ad9b87e11e/virt-serial0'/>
<target type='isa-serial' port='0'>
<model name='isa-serial'/>
</target>
<alias name='serial0'/>
</serial>
<console type='unix'>
<source mode='bind' path='/var/run/kubevirt-private/5950bc0a-fde5-4b96-9958-e7ad9b87e11e/virt-serial0'/>
<target type='serial' port='0'/>
<alias name='serial0'/>
</console>
<channel type='unix'>
<source mode='bind' path='/var/lib/libvirt/qemu/channel/target/domain-1-default_vm-fedora-dp/org.qemu.guest_agent.0'/>
<target type='virtio' name='org.qemu.guest_agent.0' state='connected'/>
<alias name='channel0'/>
<address type='virtio-serial' controller='0' bus='0' port='1'/>
</channel>
<input type='mouse' bus='ps2'>
<alias name='input0'/>
</input>
<input type='keyboard' bus='ps2'>
<alias name='input1'/>
</input>
<graphics type='vnc' socket='/var/run/kubevirt-private/5950bc0a-fde5-4b96-9958-e7ad9b87e11e/virt-vnc' sharePolicy='ignore'>
<listen type='socket' socket='/var/run/kubevirt-private/5950bc0a-fde5-4b96-9958-e7ad9b87e11e/virt-vnc'/>
</graphics>
<audio id='1' type='none'/>
<video>
<model type='vga' vram='16384' heads='1' primary='yes'/>
<alias name='video0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0'/>
</video>
<memballoon model='virtio-non-transitional' freePageReporting='off'>
<stats period='10'/>
<alias name='balloon0'/>
<address type='pci' domain='0x0000' bus='0x08' slot='0x00' function='0x0'/>
</memballoon>
</devices>
<seclabel type='dynamic' model='dac' relabel='yes'>
<label>+107:+107</label>
<imagelabel>+107:+107</imagelabel>
</seclabel>
</domain>
# 坏的 虚拟机的 xml
<domain type='kvm' id='1'>
<name>default_vm-dpdk</name>
<uuid>662f44f6-ba16-5d08-95e7-75b1ca2ff10e</uuid>
<metadata>
<kubevirt xmlns="http://kubevirt.io">
<uid/>
</kubevirt>
</metadata>
<memory unit='KiB'>2097152</memory>
<currentMemory unit='KiB'>2097152</currentMemory>
<memoryBacking>
<hugepages/> # 没有配置共享内存，导致包转发无法使用共享内存
</memoryBacking>
<vcpu placement='static'>2</vcpu>
<iothreads>1</iothreads>
<resource>
<partition>/machine</partition>
</resource>
<sysinfo type='smbios'>
<system>
<entry name='manufacturer'>KubeVirt</entry>
<entry name='product'>None</entry>
<entry name='uuid'>662f44f6-ba16-5d08-95e7-75b1ca2ff10e</entry>
<entry name='family'>KubeVirt</entry>
</system>
</sysinfo>
<os>
<type arch='x86_64' machine='pc-q35-rhel9.2.0'>hvm</type>
<boot dev='hd'/>
<smbios mode='sysinfo'/>
</os>
<features>
<acpi/>
</features>
<cpu mode='custom' match='exact' check='full'>
<model fallback='forbid'>Cascadelake-Server</model>
<vendor>Intel</vendor>
<topology sockets='1' dies='1' cores='2' threads='1'/>
<feature policy='require' name='ss'/>
<feature policy='require' name='hypervisor'/>
<feature policy='require' name='tsc_adjust'/>
<feature policy='require' name='umip'/>
<feature policy='require' name='pku'/>
<feature policy='require' name='md-clear'/>
<feature policy='require' name='stibp'/>
<feature policy='require' name='arch-capabilities'/>
<feature policy='require' name='xsaves'/>
<feature policy='require' name='rdctl-no'/>
<feature policy='require' name='ibrs-all'/>
<feature policy='require' name='skip-l1dfl-vmentry'/>
<feature policy='require' name='mds-no'/>
<feature policy='require' name='pschange-mc-no'/>
<feature policy='disable' name='erms'/>
<feature policy='disable' name='avx512vnni'/>
<feature policy='disable' name='xgetbv1'/>
<feature policy='disable' name='pdpe1gb'/>
<feature policy='disable' name='mpx'/>
</cpu>
<clock offset='utc'/>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>destroy</on_crash>
<devices>
<emulator>/usr/libexec/qemu-kvm</emulator>
<disk type='block' device='disk' model='virtio-non-transitional'>
<driver name='qemu' type='raw' cache='none' error_policy='stop' io='native' discard='unmap'/>
<source dev='/dev/root-device' index='2'/>
<backingStore/>
<target dev='vda' bus='virtio'/>
<alias name='ua-root-device'/>
<address type='pci' domain='0x0000' bus='0x05' slot='0x00' function='0x0'/>
</disk>
<disk type='file' device='disk' model='virtio-non-transitional'>
<driver name='qemu' type='raw' cache='none' error_policy='stop' discard='unmap'/>
<source file='/var/run/kubevirt-ephemeral-disks/cloud-init-data/default/vm-dpdk/configdrive.iso' index='1'/>
<backingStore/>
<target dev='vdb' bus='virtio'/>
<alias name='ua-cloudinitdisk'/>
<address type='pci' domain='0x0000' bus='0x06' slot='0x00' function='0x0'/>
</disk>
<controller type='usb' index='0' model='none'>
<alias name='usb'/>
</controller>
<controller type='scsi' index='0' model='virtio-non-transitional'>
<alias name='scsi0'/>
<address type='pci' domain='0x0000' bus='0x03' slot='0x00' function='0x0'/>
</controller>
<controller type='virtio-serial' index='0' model='virtio-non-transitional'>
<alias name='virtio-serial0'/>
<address type='pci' domain='0x0000' bus='0x04' slot='0x00' function='0x0'/>
</controller>
<controller type='sata' index='0'>
<alias name='ide'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x1f' function='0x2'/>
</controller>
<controller type='pci' index='0' model='pcie-root'>
<alias name='pcie.0'/>
</controller>
<controller type='pci' index='1' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='1' port='0x10'/>
<alias name='pci.1'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0' multifunction='on'/>
</controller>
<controller type='pci' index='2' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='2' port='0x11'/>
<alias name='pci.2'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x1'/>
</controller>
<controller type='pci' index='3' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='3' port='0x12'/>
<alias name='pci.3'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x2'/>
</controller>
<controller type='pci' index='4' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='4' port='0x13'/>
<alias name='pci.4'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x3'/>
</controller>
<controller type='pci' index='5' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='5' port='0x14'/>
<alias name='pci.5'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x4'/>
</controller>
<controller type='pci' index='6' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='6' port='0x15'/>
<alias name='pci.6'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x5'/>
</controller>
<controller type='pci' index='7' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='7' port='0x16'/>
<alias name='pci.7'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x6'/>
</controller>
<controller type='pci' index='8' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='8' port='0x17'/>
<alias name='pci.8'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x7'/>
</controller>
<interface type='vhostuser'>
<mac address='00:00:00:9d:24:bf'/>
<source type='unix' path='/var/run/kubevirt-private/dpdk01/sock' mode='server'/>
<model type='virtio-non-transitional'/>
<driver>
<host mrg_rxbuf='off'/>
</driver>
<alias name='ua-dpdk01'/>
<address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/>
</interface>
<interface type='vhostuser'>
<mac address='00:00:00:fa:29:11'/>
<source type='unix' path='/var/run/kubevirt-private/dpdk02/sock' mode='server'/>
<model type='virtio-non-transitional'/>
<driver>
<host mrg_rxbuf='off'/>
</driver>
<alias name='ua-dpdk02'/>
<address type='pci' domain='0x0000' bus='0x02' slot='0x00' function='0x0'/>
</interface>
<serial type='unix'>
<source mode='bind' path='/var/run/kubevirt-private/ca990405-9b47-4c8f-bc3a-cb63a4700980/virt-serial0'/>
<log file='/var/run/kubevirt-private/ca990405-9b47-4c8f-bc3a-cb63a4700980/virt-consolelog0.log' append='off'/>
<target type='isa-serial' port='0'>
<model name='isa-serial'/>
</target>
<alias name='serial0'/>
</serial>
<console type='unix'>
<source mode='bind' path='/var/run/kubevirt-private/ca990405-9b47-4c8f-bc3a-cb63a4700980/virt-serial0'/>
<log file='/var/run/kubevirt-private/ca990405-9b47-4c8f-bc3a-cb63a4700980/virt-consolelog0.log' append='off'/>
<target type='serial' port='0'/>
<alias name='serial0'/>
</console>
<channel type='unix'>
<source mode='bind' path='/var/lib/libvirt/qemu/channel/target/domain-1-default_vm-dpdk/org.qemu.guest_agent.0'/>
<target type='virtio' name='org.qemu.guest_agent.0' state='connected'/>
<alias name='channel0'/>
<address type='virtio-serial' controller='0' bus='0' port='1'/>
</channel>
<input type='mouse' bus='ps2'>
<alias name='input0'/>
</input>
<input type='keyboard' bus='ps2'>
<alias name='input1'/>
</input>
<graphics type='vnc' socket='/var/run/kubevirt-private/ca990405-9b47-4c8f-bc3a-cb63a4700980/virt-vnc'>
<listen type='socket' socket='/var/run/kubevirt-private/ca990405-9b47-4c8f-bc3a-cb63a4700980/virt-vnc'/>
</graphics>
<audio id='1' type='none'/>
<video>
<model type='vga' vram='16384' heads='1' primary='yes'/>
<alias name='video0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0'/>
</video>
<memballoon model='virtio-non-transitional'>
<stats period='10'/>
<alias name='balloon0'/>
<address type='pci' domain='0x0000' bus='0x07' slot='0x00' function='0x0'/>
</memballoon>
</devices>
<seclabel type='dynamic' model='dac' relabel='yes'>
<label>+107:+107</label>
<imagelabel>+107:+107</imagelabel>
</seclabel>
</domain>
libvirt内存备份有三种类型：file、anonymous和memfd。它们的详细区别如下：
- file：将内存备份保存在文件中。这种方式可以通过文件共享来实现内存共享。
- anonymous：默认的内存备份类型。它将内存备份保存在匿名内存中，无法直接共享。
- memfd：使用Linux的memfd机制来创建内存备份，可以通过文件描述符共享内存。
这些备份类型的选择取决于具体的需求和环境。
