WRT intel_iommu, it does not yet seem to be as fully functional as I hoped. People also discussed the best way to handle virtio versus iommu (it bypasses it ATM). I'd like to suggest we hide the iommu from the command line help for 2.2, this way people don't activate it mistakenly.
Let's make it more complete and then enable for 2.3. Thoughts? -- MST
