[Kimchi-devel] RFC - PCI Hot Plug

[Daniel Henrique Barboza]

On 03/27/2015 03:22 PM, Jose Ricardo Ziviani wrote:
> Hello everybody!
>
> I tried PCI Hot Plug in Kimchi but it didn't work as expected. Once my 
> VM was running I plugged my audio device into my VM successfully, I 
> was able to use it flawlessly.
>
> However, if I reboot (or completely turn off/on), the VM will not boot 
> anymore. It tries to exclusively get the device but for some reason 
> (libvirt bug?) that device was not detached from the host. Then, I 
> must to turn off the VM amd remove the PCI using Kimchi to be able to 
> boot it again.

Unfortunately the only way to tell if it's Kimchi or libvirt's fault is 
to try to do the
whole process without Kimchi. In other words, creating the VM and 
plug/unplug
the PCI devices using virsh.

>
> Such behavior doesn't happen if I add the PCI when the VM is turned 
> off. Also, virt-manager doesn't look to support hot plug, it throws a 
> libvirt exception (libvirtmod.virDomainAttachDevice) if I try to add a 
> PCI while VM is running.


virt-manager can be a good benchmark of libvirt current capabilities ( I 
believe both are
maintained by Red Hat). If latest virt-manager does not support PCI hot 
plug there is a good
chance that libvirt support for this feature is not complete or it is in 
early stages.

This only makes libvirt only testing more critical. We need to determine 
exactly where
libvirt is as far as PCI Hot Plug is concerned.

>
> Does anybody have experienced it before, any advise?
>
> Thank you
>
>