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kernel-package

NAME

kernel-package - A system for creating kernel related packages

DESCRIPTION

The kernel-package package grew out of desire to automate the routine steps required to compile and install a custom kernel. If you are looking for instructions on how to use kernel-package, please have a look at the manual make-kpkg (1). Configuring instructions are to be found in kernel-pkg.conf(5).

Advantages of using kernel-package

i) Convenience.

I used to compile kernels manually, and it involved a series of steps to be taken in order; kernel-package was written to take all the required steps (it has grown beyond that now, but essentially, that is what it does). This is especially important to novices: make-kpkg takes all the steps required to compile a kernel, and installation of kernels is a snap.

ii) Multiple images support

It allows you to keep multiple version of kernel images on your machine with no fuss.

iii) Multiple Flavors of the same kernel version

It has a facility for you to keep multiple flavors of the same kernel version on your machine (you could have a stable 2.0.36 version, and a 2.0.36 version patched with the latest drivers, and not worry about contaminating the modules in /lib/modules).

iv) Built in defaults

It knows that some architectures do not have vmlinuz (using vmlinux instead), and other use zImage rather than bzImage, and calls the appropriate target, and takes care of moving the correct file into place.

v) Module hooks

Several other kernel module packages are hooked into kernel-package, so one can seamlessly compile, say, pcmcia modules at the same time as one compiles a kernel, and be assured that the modules so compiled are compatible.

vi) dpkg support

It enables you to use the package management system to keep track of the kernels created. Using make-kpkg creates a .deb file, and dpkg can track it for you. This facilitates the task of other packages that depend on the kernel packages.

vii) Configuration tracking

It keeps track of the configuration file for each kernel image in /boot, which is part of the image package, and hence is the kernel image and the configuration file are always together.

viii) Multiple config files

It allows you to specify a directory with config files, with separate config files for each sub-architecture (even allows for different config files for i386, i486, etc). It is really neat for people who need to compile kernels for a variety of sub architectures.

ix) Auxiliary kernel .deb packages

It allows to create a package with the headers, or the sources, also as a deb file, and enables the package management system to keep track of those (and there are packages that depend on the package management system being aware of these packages).

x) Maintainer script services

Since the kernel image package is a full fledged Debian package, it comes with maintainer scripts, which take care of details like offering to make a boot disk, manipulating symbolic links in / so that you can make boot loader scripts static (just refer to the symbolic links, rather than the real image files; the names of the symbolic links do not change, but the kernel image file names change with the version).

xi) Sub architecture support

There is support for the multitudinous sub architectures that have blossomed under the umbrella of the m68k and power-PC architectures.

xii) kernel-patch support

There is support there for optionally applying patches to the kernel provided as a kernel-patch .deb file, and building a patched kernel auto-magically, and still retain an UN-patched kernel source tree.

xiii) Portable kernel images

Allows one to compile a kernel for another computer, for example using a fast machine to compile the kernel for installation on a slower machine. This is really nice since the modules are all included in the .deb; and one does not have to deal with modules manually.

xiv) Customizations on the target host

The postinst looks at a configuration file on the installation machine (as opposed to the machine that the image was compiled on), and allows the local admin to decide on issues of symbolic links, and whether the boot loader stuff must be run, and whether one wants to create a boot floppy or not.

xv) runtime hooks

The postinst and the postrm scripts allow the local admin on the installation machine to add a script into runtime hooks; this can allow, amongst other things, grub users to add and remove kernel image stanzas from the grub menu (example scripts to do this are in the package).

xvi) Append descriptive bits to the kernel version

One can append to the kernel version on the command line, or by setting an environment variable. So if your kernel is called kernel-image-2.4.1John.Home; it is unlikely to be overridden by the official 2.4.1 kernel, since they are not the same version.

Disadvantages of using make-kpkg

i) Automation.

This is a cookie cutter approach to compiling kernels, and there are people who like being close to the bare metal.

ii) Non traditional

This is not how it is done in the non-Debian world. This flouts tradition. (It has been pointed out, though, that this is fast becoming Debian tradition).

iii) Needs superuser

It forces you to use fakeroot or sudo or super or be root to create a kernel image .deb file (this is not as bad as it used to be before fakeroot)

FILES

/etc/kernel-pkg.conf. /etc/kernel-img.conf.

SEE ALSO

make-kpkg(1), make(1), The GNU Make manual.

BUGS

There are no bugs. Any resemblance thereof is delirium. Really.

AUTHOR

This manual page was written by Manoj Srivastava <srivasta@debian.org>, for the Debian GNU/Linux system.