[libvirt] [Question] About ivshmemory device and slot number confliction.

[Jiri Denemark]

On Tue, Jan 28, 2014 at 09:17:46 +0000, Wangyufei (James) wrote:
> Hello,
> 
> I want to use ivshmemory device which is supported by qemu, but libvirt does not support it. 
> So I use qemu:commandline to make ivshmemory device in qemu command pass-through. 
> But then hot-plug a virtio-net device failed. 
> The reason is that a qemu:commandline pci device's slot number is assigned by qemu not libvirt.
> And hot-plug device's slot is assigned by libvirt.
> So it failed beacause of slot confliction.
> 
> I have two questions to ask:
> 1. Why libvirt does not support ivshmemory device? If libvirt intends to support it, when?

There were some attempts to start implementing ivshmemory support for
libvirt but no real patches were provided. It seems nobody is interested
enough to actually write support for this in libvirt.

> 2. Can libvirt handle with qemu:commandline pci device's slot number?
> Just like pci:commandline to assign a slot number. what's your
> opinion?

No. If you use qemu:commandline you need to handle that yourself and
explicitly specify PCI addresses when hotplugging additional devices so
that no collision occurs.

Jirka