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 Flavours of the same kernel version
It has a facility for you to keep multiple flavours 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)