[libvirt] [PATCH v2 2/2] Allow PCI virtio on ARM "virt" machine

[Cole Robinson]

On 06/29/2015 02:52 AM, Pavel Fedin wrote:
>  Hello! PING!
> 
>> We can't apply this without unit test additions. We will at least need a test
>> for qemu 2.3+ defaulting to PCI, and a test to ensure that manually specified
>> virtio-mmio continues to do the correct thing. I'll take a stab at it this week
> 
>  How are things going? Something like 2 weeks have passed.

Sorry, I've been slacking.

Unfortunately thinking about this some more, the current patch approach might
not be acceptable as is, since current distros as a guest don't support -M
virt with PCI... for example Fedora 21 or 22. But they _do_ work with
virtio-mmio. So I don't know if we can or should change the default outright
to virtio-pci when qemu supports it.

Maybe when we get versioned -M virt types we can key off a more modern type.
Dunno, I have to play with it all first to get a better idea.

That said, patches that just allow using pci instead of mmio if the user
explicitly requests it should be fine for now before we consider if/how to
change the default from mmio to pci.

>  I could write these tests if somebody explains me how our unit-testing works and where to put them.
> 

Read HACKING bits about 'make check'. The main tests you'll be extending here
are tests/qemuxml2argvtest.c with data in tests/qemuxml2argvdata/. Check the
existing aarch64 and arm ones to get an idea, or look at some of my previous
commits regarding arm/aarch64 for examples

- Cole