Separating Translation from Protection in Address Spaces with Dynamic Remapping

• DOI: 10.1145/3102980.3103000
• Publication Date: 2017-07-20T13:51:38Z
• Authors: Reto Achermann; Chris Dalton; Paolo Faraboschi; Moritz Hoffmann; Dejan Milojicic; Geoffrey Ndu; Alexander Richardson; Timothy Roscoe; Adrian L. Shaw; Robert N. M. Watson
• Keywords: 0103 physical sciences; 0202 electrical engineering, electronic engineering, information engineering; 02 engineering and technology; 01 natural sciences

It is time to reconsider memory protection. The emergence of large non-volatile main memories, scalable interconnects, and rack-scale computers running large numbers of small "micro services" creates significant challenges for memory protection based solely on MMU mechanisms. Central to this is a tension between protection and translation: optimizing for translation performance often comes with a cost in protection flexibility.We argue that a key-based memory protection scheme, complementary to but separate from regular page-level translation, is a better match for this new world. We present MaKC, a new architecture which combines two levels of capability-based protection to scale fine-grained memory protection at both user and kernel level to large numbers of protection domains without compromising efficiency at scale or ease of revocation.