hpe-apollo-cn99xx says it only supports 512M hugepages, so hugepages=128 fails on the systems. Even trying to set hugepages=1 when diagnosing the issue doesn't get any hugepages created. So for now iommufd selftest should probably avoid the hpe-apollo-cn99xx systems.

A couple other things to do:

• Tell the kernel which size hugepage to set the hugepages up for.
• Add code to kselftest to check that the hugepages exist before attempting to run the selftest.
• No need to pass intel_iommu=off to the intel system. intel_iommu will not be enabled unless you pass the kernel intel_iommu=on.
• Clean up the files that cause the test to trigger. The arm iommufd test shouldn't run when there has only a change to intel iommu code, and vice versa.