Up until a while ago, libvirt would automatically add a legacy
PCI controllers combo (dmi-to-pci-bridge + pci-bridge) to any
PCIe machine type (x86_64/q35 and aarch64/virt).
As a result, a number of input and output files in the test
suite ended up containing the legacy PCI controllers, even
though they are not needed or in any way relevant to the
feature being tested.
Get rid of most of the occurrences. Most of the time, this
just means removing the controllers from the input file and
regenerating the output files; in a few instances, some
minor tweaking is performed on the input file, most notably
removing the memory balloon: as memory balloon support was
not the scope of the test being changed, there is no loss
of test coverage from doing so.
Several occurrences of the legacy PCI controllers remain in
the test suite, both because removing their usage would have
required even more tweaking, and because we still want to
have coverage of this perfectly valid combination.
The intel-iommu device has existed since QEMU 2.2.0, but
it was only possible to create it with -device since
QEMU 2.7.0, thanks to:
commit 621d983a1f9051f4cfc3f402569b46b77d8449fc
Author: Marcel Apfelbaum <marcel@redhat.com>
Date: Mon Jun 27 18:38:34 2016 +0300
hw/iommu: enable iommu with -device
Use the standard '-device intel-iommu' to create the IOMMU device.
The legacy '-machine,iommu=on' can still be used.
The libvirt capability check & command line formatting code
is thus broken for all QEMU versions 2.2.0 -> 2.6.0 inclusive.
This fixes it to use iommu=on instead.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>