//! x86_64 machine setup for the KVM backend.
//!
//! Counterpart to `arch::aarch64` (GIC/PSCI/FDT/layout) for the other host
//! architecture. Where aarch64 hands the kernel a flattened device tree, x86
//! hands it `struct boot_params` (the "zero page") plus an e820 map and a GDT,
//! and enters long mode directly — see [`boot`].
//!
//! Only the boot protocol lives here so far; the platform devices (16550 UART,
//! virtio-mmio transport) live under `crate::devices`, driven by the KVM run
//! loop via `VcpuExit::{Io, Mmio}`.