On Tue, 2016-01-05 at 13:08 +0100, Christoffer Dall wrote: > On Tue, Jan 05, 2016 at 12:37:02PM +0100, Andrea Bolognani wrote: > > On Mon, 2015-12-21 at 12:03 +0100, Christoffer Dall wrote: > > > > > > So let me summarize the things we need to do: > > > > > > - patch libvirt to allow <gic version='host' /> > > > - patch libvirt to properly probe for GICv2 and GICv3 support > > > - patch libvirt to generally handle virt-host-validate on ARM > > > > > > And that should be enough for other tools such as OpenStack with Nova to > > > probe and create the VMs it wishes. > > > > > > Does that about capture it? > > > > Sounds about right. > > > > I can work on points 1) and 3) of your list on my own, but for point 2) > > we need QEMU to start probing the host for supported GIC versions and > > expose such information before libvirt can use it. Then of course higher > > level tools such as OpenStack will need to become aware of these new > > features in libvirt. > > > I thought the virt-host-validate tool in libvirt should do the probing > directly? The tool is just a convenience for the administrator (and for higher level tools?), and it can't be where the validation happens for two reasons: - it doesn't take any argument, so it can't possibly know whether you're interested in running GICv2 or GICv3 guests - libvirt needs to check before running the guest anyway Probing inside QEMU means libvirt can just ask it instead of implementing the checks itself, which means less code duplication; more importantly, this prevents the possibility of the checks ever going out of sync. > If I misunderstood, how would you like QEMU to report this? I'm not 100% sure about the best interface here (hopefully other people can weigh in) but I imagine there would be some sort of QMP command that lists the GIC versions supported by the QEMU binary, or some text in the output of 'qemu -help' that can be parsed to obtain such list. > Should it > be the qemu binary directly or the script that Peter suggested? I think it should be the QEMU binary, especially since I assume QEMU itself will want to error out if an unsupported GIC version is requested by the user - there's no guarantee QEMU will be called by libvirt, so it will have to check on its own. Cheers. -- Andrea Bolognani Software Engineer - Virtualization Team -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list