What: /sys/kernel/iommu_groups/ Date: May 2012 KernelVersion: v3.5 Contact: Alex Williamson <alex.williamson@redhat.com> Description: /sys/kernel/iommu_groups/ contains a number of sub- directories, each representing an IOMMU group. The name of the sub-directory matches the iommu_group_id() for the group, which is an integer value. Within each subdirectory is another directory named "devices" with links to the sysfs devices contained in this group. The group directory also optionally contains a "name" file if the IOMMU driver has chosen to register a more common name for the group. Users: What: /sys/kernel/iommu_groups/reserved_regions Date: January 2017 KernelVersion: v4.11 Contact: Eric Auger <eric.auger@redhat.com> Description: /sys/kernel/iommu_groups/reserved_regions list IOVA regions that are reserved. Not necessarily all reserved regions are listed. This is typically used to output direct-mapped, MSI, non mappable regions. Each region is described on a single line: the 1st field is the base IOVA, the second is the end IOVA and the third field describes the type of the region. What: /sys/kernel/iommu_groups/reserved_regions Date: June 2019 KernelVersion: v5.3 Contact: Eric Auger <eric.auger@redhat.com> Description: In case an RMRR is used only by graphics or USB devices it is now exposed as "direct-relaxable" instead of "direct". In device assignment use case, for instance, those RMRR are considered to be relaxable and safe. |