KVM VMX changes for 7.4 - Enable Notify VM-Exits (now called Instruction Timeout in the SDM) and Bus Lock VM-Exits for TDX guests when they're enabled by userspace (KVM forgot to wire up the TDX Module knobs). - Move all common (between VMX and TDX) APIs/helpers to common.h/main.c, and change all namespace prefixes from "vmx" to "vt". - Fix a thankfully benign bug (due to other areas of KVM being hardened) where usersepace can bypass INIT_MEM_REGION's address wrap check by providing a nr_pages that will overflow a u64 when converted to bytes, and fix an also- benign off-by-one bug in the check (inclusive vs. exclusive). - Set the vmcs.GUEST_ACTIVITY_STATE back to ACTIVE when userspace sets KVM's mp_state to anything other than HALTED, e.g. so that a vCPU doesn't get stuck in HLT if userspace emulates RESET.