Furthermore, I do not see an implementation only implementing zicfilp while not implementing zicfiss. There is a case of a nommu case where only zicfilp might be implemented and no zicfiss. However that's the case which is anyways riscv linux kernel is not actively being tested. IIRC, it was (nommu linux) considered to be phased out/not supported as well. We could have two different configs but I don't see what would serve apart from the ability to build support for landing pad and shadow stack differently. As I said from a usability point of view both features are complimenting to each other rather than standing out alone and providing full protection. A kernel is built with support for enabling both features or none. Sure user can use either of the prctl to enable either of the features in whatever combination they see fit.
