[libvirt] [PATCH v3 8/8] conf: aggregate multiple pcie-root-ports onto a single slot

[Andrea Bolognani]

On Tue, 2017-01-10 at 15:51 -0500, Laine Stump wrote:
> ARGH!

ARGH to you too :)

> In my final rebase before pushing, I pulled in Andrea's patches that 
> switch aarch64/virt to using PCI by default, and the test case for that 
> resulted in a make check failure:
> 
> 564) QEMU XML-2-ARGV aarch64-virtio-pci-default ... libvirt: QEMU Driver 
> error : unsupported configuration: 'multifunction=on' is not supported 
> with this QEMU binary FAILED
> 
> Is it really true that the aarch64 qemu doesn't support multifunction 
> devices? If so, that really needs to be fixed. In the meantime, this 
> means I still can't push my patches, because doing so will break 
> aarch64.

I think the only problem is that current aarch64 test cases
don't enable the QEMU_CAPS_PCI_MULTIFUNCTION capability.

I will try this on actual hardware now and get back to you,
but really that's all you should have to do in order not to
break the test suite with your changes.

> I'll try to come up with a patch to conditionalize 
> AGGREGATE_SLOT on support for multifunction (which I suppose I should 
> have done to begin with, but I wouldn't have expected that a platform 
> that supports PCIe doesn't support multifunction devices :-/)

That's a good idea in any case, yes. However, realistically
speaking, I think your initial intuition that all platforms
that support PCIe also support multifunction still holds as
far as real-world scenarios are concerned.

-- 
Andrea Bolognani / Red Hat / Virtualization