Merge git://git.infradead.org/iommu-2.6

* git://git.infradead.org/iommu-2.6:
  intel-iommu: Force-disable IOMMU for iGFX on broken Cantiga revisions.
  intel-iommu: Fix double lock in get_domain_for_dev()
  intel-iommu: Fix reference by physical address in intel_iommu_attach_device()