Hi all, I've been working on a patchset that brings the sun4u machine on qemu-system-sparc64 much closer to a real Ultra 5, however due to various design restrictions I need to be able to restrict how devices are added to the machine with -device.
On a real Ultra 5, the root PCI bus (sabre) has 2 PCI bridges (simba A and simba B) with the onboard devices attached to simba A with 2 free slots, and an initially empty simba B. Firstly, is it possible to restrict the machine so that devices cannot be directly plugged into the root PCI bus, but only behind one of the PCI bridges? There is also an additional restriction in that slot 0 behind simba A must be left empty to ensure that the ebus (containing the onboard devices) is the first device allocated. Secondly, how does libvirt handle these type of restrictions? Is it able to get the information from QEMU or is there some kind of libvirt profile that needs to be updated? And do newer versions of libvirt have the ability to attach devices behind PCI bridges using a GUI such as virt-manager, or is that only something that can only be done by directly editing the domain XML? ATB, Mark.
