[Kimchi-devel] RFC - PCI Hot Plug

[Jose Ricardo Ziviani]

On 30-03-2015 11:01, Daniel Henrique Barboza wrote:
>
> 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
>>
>>
>
> _______________________________________________
> Kimchi-devel mailing list
> Kimchi-devel at ovirt.org
> http://lists.ovirt.org/mailman/listinfo/kimchi-devel
>

Daniel,

Thank you for all the information. I tested here again and it worked fine.

In my VM I was running Debian with an older kernel. Now, with Ubuntu 
10.10 it worked flawlessly. That problem reported seems to be the guest 
running an older kernel, nothing to do with libvirt or kimchi.

I'll continue my testing using different combinations. I'll report here 
as soon as possible (unfortunately my network is not good today).

Regards!

-- 
Jose Ricardo Ziviani
-----------------------------
Software Engineer
Linux Technology Center - IBM