1.6.2 Booting Kernels

 

The example kernels, as well as custom kernels you build using the OSKit, can be booted from either the GRUB, Linux, Mach, or BSD boot loaders, from MS-DOS directly, or from the NetBoot ``meta-kernel.'' (NetBoot is described in Section 33.) GRUB and NetBoot can boot the kernels as-is, since they directly support the MultiBoot standard, whereas the other boot loaders need the kernel to be in a different format. This conversion can be done with the mkbsdimage, mklinuximage, and mkdosimage ``boot adapter'' scripts, which are automatically built and installed with the OSKit when configured for the appropriate host:

• The mklinuximage script is installed with the OSKit when configured for a Linux or other ELF-based host; given a MultiBoot boot image, it creates a standard Linux boot image that can be loaded from LILO or other Linux boot loaders.
• The mkbsdimage script is installed when the OSKit is configured for a Mach or BSD host; its script creates an NMAGIC a.out image from a MultiBoot image that can be loaded from any of the BSD or Mach boot loaders. Note that mkbsdimage requires GNU ld to work properly: on BSD systems, which don't normally use GNU ld, you will have to build and install GNU ld manually.
• The mkdosimage script is installed when the OSKit is configured for DOS-based targets such as i386-msdos and i386-moss. Like the mkbsdimage script, mkdosimage requires GNU ld; you may have to build and install GNU ld first, configured as a cross-inker for an MS-DOS target, before mkdosimage will build properly.
• The mkmbimage is installed with all OSKit configurations And, unlike the other scripts, doesn't do any conversion. It simply allows for the combining of a kernel and additional files into one MultiBoot image. The resulting image can be used with MultiBoot boot loaders such as GRUB and NetBoot.

For example, the following command creates a bootable BSD-style image named `Image':

% mkbsdimage hello

the mktypeimage scripts can also do more complex things, such as combining an arbitrary number of additional files or ``boot modules'' into the image. See 10.14 and the scripts for more info.

For details on the MultiBoot standard see Section 10.14.12.