Linux From Scratch: Version 5.0-pre3
Prev | Chapter 8. Making the LFS system bootable | Next

# Installing Linux-2.4.22

    Estimated build time:           All default options: 4.20 SBU
    Estimated required disk space:  All default options: 181 MB

## Contents of Linux

(Last checked against version 2.4.22.)

The Linux kernel is at the core of every Linux system. It's what makes Linux tick. When a computer is turned on and boots a Linux system, the very first piece of Linux software that gets loaded is the kernel. The kernel initializes the system's hardware components: serial ports, parallel ports, sound cards, network cards, IDE controllers, SCSI controllers and a lot more. In a nutshell the kernel makes the hardware available so that the software can run.

Installed files: the kernel and the kernel headers

##

## Linux Installation Dependencies

(Last checked against version 2.4.17.)

Bash: sh
Binutils: ar, as, ld, nm, objcopy
Coreutils: basename, cat, cp, date, expr, ln, md5sum, mkdir, mv,
pwd, rm, sort, stty, tail, touch, uname, whoami, yes
Findutils: find, xargs
Gawk: awk
GCC: cc1, collect2, cpp, gcc
Grep: grep
Gzip: gzip
Make: make
Modutils: depmod, genksyms
Net-tools: dnsdomainname, hostname
Sed: sed

##

## Installation of the kernel

Building the kernel involves a few steps: configuration, compilation, and installation. If you don't like the way this book configures the kernel, view the `README` file in the kernel source tree for alternative methods.

Prepare for compilation by running the following command:

    make mrproper

This ensures that the kernel tree is absolutely clean. The kernel team recommends that this command be issued prior to each kernel compilation. You shouldn't rely on the source tree being clean after untarring.

Configure the kernel via a menu-driven interface:

    make menuconfig

`make oldconfig` may be more appropriate in some situations. See the `README` file for more information.

If you wish, you may skip kernel configuration by simply copying the kernel config file, `.config`, from your host system (assuming it is available) to the unpacked `linux-2.4.22` directory. However, we don't recommend this option. You're much better off exploring all the configuration menus and creating your own kernel configuration from scratch.

For POSIX shared memory support, ensure that the kernel config option "Virtual memory file system support" is enabled. It resides within the "File systems" menu and is normally enabled by default.

Verify dependencies and create dependency information files:

    make CC=/opt/gcc-2.95.3/bin/gcc dep

Compile the kernel image:

    make CC=/opt/gcc-2.95.3/bin/gcc bzImage

Compile the drivers which have been configured as modules:

    make CC=/opt/gcc-2.95.3/bin/gcc modules

If you intend to use kernel modules, you will need an `/etc/modules.conf` file. Information pertaining to modules and to kernel configuration in general may be found in the kernel documentation, which is found in the `linux-2.4.22/Documentation` directory. The modules.conf man page and the kernel HOWTO at http://www.tldp.org/HOWTO/Kernel-HOWTO.html may also be of interest to you.

Install the modules:

    make CC=/opt/gcc-2.95.3/bin/gcc modules_install

As nothing is complete without documentation, build the manual pages that come with the kernel:

    make mandocs

And install these pages:

    cp -a Documentation/man /usr/share/man/man9

Kernel compilation has finished, but some of the files created still reside in the source tree. To complete the installation, two files should to be copied to the `/boot` directory.

The path to the kernel file may vary depending on the platform you're using. Issue the following command to install the kernel:

    cp arch/i386/boot/bzImage /boot/lfskernel

`System.map` is a symbol file for the kernel. It maps the function entrypoints of every function in the kernel API, as well as the addresses of the kernel data structures for the running kernel. Issue the following command to install the map file:

    cp System.map /boot

Prev | Home | Next
Creating the /etc/fstab file | Up | Making the LFS system bootable