jmmv writes: "The Multiboot Specification defines a protocol between boot loaders and operating systems' kernels with the basic aim to allow any compliant boot loader to launch any compliant OS. This simplifies the boot loader's tasks by reducing the amount of knowledge it must have of foreign OSes and, as a side effect, it also removes the burden of writing a custom boot loader for each OS. A while ago I modified the NetBSD's kernel to support this specification, which means that the upcoming 4.0 release will be easier to boot on any dual-boot system with Linux installed (assuming it uses GRUB). I've written an article, titled Making NetBSD Multiboot-Compatible, that provides an introduction to The Multiboot Specification and outlines the steps I took to adapt the NetBSD's kernel to follow it. This can give you enough interest and clues to modify your favourite operating system to also support this protocol."