Grant V3 introduction
Owner: jgross
Time: Thu 1:45 PM 22 Sep +0100 (Europe/Berlin) Final
Location: Fitzwilliam (5th floor #501)

Today the grant interface supports 2 variants: grant V1, which is the mostly used variant, and grant V2, which hasn’t seen much adaptions due to several design problems, but is needed for large hosts exceeding physical addresses beyond 16 TB. Additionally new use cases of grants (especially virtio) and problems with driver domain reboots can only be solved in complex or non-optimal ways. We should think about a grant V3 interface solving all those problems by: - making it more like an IOMMU interface (tree based table with grantee for a whole tree) - introducing “virtual” domids (guest local domids assigned to devices, not to backends)