CHERI is an attempt. DARPA paid to have it for RISC-V and ARMv8. It was originally for MIPS. https://www.cl.cam.ac.uk/research/security/ctsrd/cheri/ https://ww

CHERI is an attempt. DARPA paid to have it for RISC-V and ARMv8. It was originally for MIPS. https://www.cl.cam.ac.uk/research/security/ctsrd/cheri/ https://www.cl.cam.ac.uk/research/security/ctsrd/cheri/ It is fundamentally like the 80286 segments, but with all sorts of usability troubles solved. The 80286 segments were impractical because there were a small number available and because the OS couldn't safely hand over direct control. Every little segment adjustment required calling the OS.