USB Auto mapping to Windows VM under KVM does not work

Let me first say, that it does work for Linux guest. It doesn’t work on Windows guest because there is a know bug (/issue) with the default hardware layout – made of i440FX BIOS. VirtManager would not allow us to replace the settings, so we need to create the VM ourselves using XML. You can export your XML settings (of an existing VM) using the command

virsh dumpxml  > /tmp/VM_NAME.xml

There are relevant fields there which you might want to save for later, like MAC addresses, network settings, and so on.

You can use this XML file to build your VM anew. Note that you will want to modify the network settings, the name and the UUID. Also – you will need a newer QEMU command (through the package qemu-system-x86), you can find in the Centos updates repository, . It has been providing me with /usr/bin/qemu-system-x86_64 command, which I am using, instead of the default qemu command used by default by VirtManager.

My Windows VM XML file (as a reference you can copy and use) is provided below. Major modifications are required to the hardware settings of the Windows VM – moving from PCI to PCIE, changing from IDE to SATA or VirtIO – and the provided XML gives a good reference of how this file should look like. This was taken from a machine tested to allow USB hot-add/remove via the method provided in my previous post.

  Windows                             
  9a10dc43-5c39-411d-8dc9-f6c6b849d212 
  4194304
  4194304
  2
  
    /machine
  
  
    hvm 
  
  
    
    
    
      
      
      
    
  
  
    
    
    
    
  
  destroy
  restart
  destroy
  
    
    
  
  
    /usr/bin/qemu-system-x86_64 
    
      
        
      
       
      
      

    
    
      
      
      
      
      
      
      

    
    
      
      

    
    
      
      
      

    
    
      
      
      

    
    
      
      
      

    
    
      
    
    
      
      
      

    
    
      
      
      
      

    
    
      
      
      
      

    
    
      
      

    
    
      
      

    
    
        
      
          
      
      

    
    
      
      
      
    
    
      
      
      
    
    
      
      
      

    
    
      
      

    
    
      
    
    
      
    
    
      
      
    
    
      
      

    
    

Now just import the VM using

virsh define /tmp/NEW_MACHINE.xml

and your changes are available via VirtManager, where you can edit (some of them).