Re: [libvirt] [PATCH] qemu: Permit PCI-free aarch64 mach-virt guests

On 06/17/2016 11:46 AM, Martin Kletzander wrote: > On Fri, Jun 17, 2016 at 11:36:05AM -0400, Laine Stump wrote: >> On 06/17/2016 08:43 AM, Andrea Bolognani wrote: >>> * other than the pcie-root. This is so that there will be >>> hot-pluggable >>> - * PCI slots available >>> + * PCI slots available. >>> + * >>> + * We skip this step for aarch64 mach-virt guests, where we >>> want to >>> + * be able to have a pure virtio-mmio topology >>> */ >>> if (virDomainControllerFind(def, >>> VIR_DOMAIN_CONTROLLER_TYPE_PCI, 1) < 0 && >>> + !qemuDomainMachineIsVirt(def) && >> >> You're assuming that the only virt* machinetypes will be aarch64, which >> may be reasonable now, but not in the future (periodically someone from >> qemu will mention the idea of a "virt" machinetype for x86, which is >> legacy-free and accepts only virtio devices). Wouldn't a more specific >> comparison be better here (and in the other places in this patch)? >> > > Just my $.02 here, but since our qemuDomainMachineIsVirt() is made > specifically for aarch64 arches, I think the right thing to do would be > just add architecture check into that function as using it throughout > the codebase ought to actually be what all the callers want. Sure, a single function would be great. Its name should reflect that it is for *aarch64* virt machines though (in anticipation of other arches getting a virt machinetype).