A) and b) are not really a problem (you don't need solutions to be universal to be useful), c) is solvable (e.g. pause any programs trying to access unavailable

A) and b) are not really a problem (you don't need solutions to be universal to be useful), c) is solvable (e.g. pause any programs trying to access unavailable memory), d) is trivial, implement it as daemon that has pre-allocated (and locked) sufficient memory