I wonder... With MS's virtualization based security, and the Arm/Cheri proposals, if it isn't time to revisit much of the capability hardware that AMD removed w

I wonder... With MS's virtualization based security, and the Arm/Cheri proposals, if it isn't time to revisit much of the capability hardware that AMD removed when they designed long mode. Never mind the long list of C mitigation hardware that both intel and arm are now reinventing. The 4 layer security architecture that the 386 originally proposed, user, privileged library/service, driver space, and kernel, now with the addition of a hypervisor layer would be a good starting place for modern OS privilege separation. Plus base + size restricted pointers with an attached privilege provided by the 386's variable length segments are the kinds of things that CHERI is trying to bolt on using a slightly different paradigm. Even call gates if used between different modules/etc would have acted as a control flow mitigation technique likely partially obliviating the need for CET, PAC and BTI. So it wouldn't surprise me at all, if in another 20 years 90% of the 386's capability model has been bolted back onto AMD's long mode in a slightly different, and likely worse way.