Three Main Privilege Levels

from blog Daniel Mangum, | ↗ original
Today’s @risc_v Tip: RISC-V systems may support 3 main privilege levels: Machine (M) (Req.) Supervisor (S) (Opt.) User (U) (Opt.) Execution context changes via traps. A trap that moves to a higher privilege level is a vertical trap, one that does not is a horizontal trap. Original Tweet