使用passthrough模式，只通过PCI任意设备（该过程是在RHEL7系统进行，其他系统原理一样）

1.在HOST 选择PCI设备

[root@localhost~]# dmesg |grep -e DMAR -e IOMMU

[    0.000000] ACPI: DMAR 000000007b7be000 00120(v01 INSYDE  HSW-LPT 00000001 ACPI00040000)

[    0.155894] dmar: IOMMU 0: reg_base_addrfbffc000 ver 1:0 cap 8d2078c106f0466 ecap f020df

[    0.155899] dmar: IOMMU 1: reg_base_addrc7ffc000 ver 1:0 cap 8d2078c106f0466 ecap f020df

[    0.156023] IOAPIC id 10 under DRHD base  0xfbffc000 IOMMU 0

[    0.156024] IOAPIC id 8 under DRHD base  0xc7ffc000 IOMMU 1

[    0.156025] IOAPIC id 9 under DRHD base  0xc7ffc000 IOMMU 1

 

 

2. 选择要使用的passthrough设备

a.

[root@localhost ~]# lspci -nn |grep NVIDIA

06:00.0 3D controller [0302]: NVIDIA Corporation Device [10de:15f8](rev a1)

87:00.0 3D controller [0302]: NVIDIACorporation Device [10de:15f8] (rev a1)

PCI bus number: PCIdevice number.Function number

 

b.查看所有的PCI接口

 $virsh nodedev-list --tree

 

c.

可以查看两个PCI的接口对应了NVIDIA 设备

 

[root@localhost ~]# virsh nodedev-dumpxml pci_0000_06_00_0

<device>

 <name>pci_0000_06_00_0</name>

 <path>/sys/devices/pci0000:00/0000:00:03.0/0000:06:00.0</path>

 <parent>pci_0000_00_03_0</parent>

  <driver>

   <name>nvidia</name>

  </driver>

  <capabilitytype='pci'>

   <domain>0</domain>

    <bus>6</bus>

   <slot>0</slot>

   <function>0</function>

    <product id='0x15f8'/>

    <vendorid='0x10de'>NVIDIA Corporation</vendor>

    <numa node='0'/>

    <pci-express>

      <link validity='cap'port='0' speed='8' width='16'/>

      <link validity='sta'speed='8' width='16'/>

    </pci-express>

  </capability>

</device>

 

[root@localhost~]# virsh nodedev-dumpxml pci_0000_87_00_0

<device>

  <name>pci_0000_87_00_0</name>

 <path>/sys/devices/pci0000:80/0000:80:03.0/0000:87:00.0</path>

  <parent>pci_0000_80_03_0</parent>

  <driver>

    <name>nvidia</name>

  </driver>

  <capability type='pci'>

    <domain>0</domain>

    <bus>135</bus>

    <slot>0</slot>

    <function>0</function>

    <product id='0x15f8' />

    <vendor id='0x10de'>NVIDIACorporation</vendor>

    <numa node='1'/>

    <pci-express>

      <link validity='cap' port='0'speed='8' width='16'/>

      <link validity='sta' speed='8'width='16'/>

    </pci-express>

  </capability>

</device>

 

 

 

 

3. 将设备从宿主机解除绑定

echo "10de 15f8" >/sys/bus/pci/drivers/pci-stub/new_id

echo 0000:06:00.0> /sys/bus/pci/devices/0000:06:00.0/driver/unbind  ###为PCI的ID number

echo 0000:06:00.0 > /sys/bus/pci/drivers/pci-stub/bind            ###为PCI的IDnumber

 

4. 编辑grub，启动项，来打开IOMMU功能模块。（VFIO等报错的时候，是因为没启用该功能）

 $vim /etc/default/grub

添加：intel_iommu=on

使其生效要进行：

update-grub

reboot

 

5. 关闭SElinux安全策略(目前生产环节的机器状态为disable)

Setenforce 0

Getenforce

永久修改：vim /etc/selinux/config

6. 在对应的VM添加PCI设备

<devices> …

  

<hostdev mode='subsystem' type='pci' managed='yes'>

      <source>

        <addressdomain='0x0000' bus='0x87' slot='0x00' function='0x0'/>

      </source>

       </hostdev>

</devices>

 

7. 启动VM，virsh start vm-03

192.168.122.15   0x1            virbr0

192.168.122.142  0x1             virbr0