Provided by:
kernel-package_9.001ubuntu15_all 
NAME
kernel-img.conf - site wide configuration file for kernel image
packages
SYNOPSIS
/etc/kernel-img.conf
DESCRIPTION
The file /etc/kernel-img.conf is a simple file looked at by the kernel
image post installation process to allow local options for handling
some aspects of the installation, overriding the defaults built into
the image itself.
The format of the file is a simple VAR = VALUE pair. Boolean values may
be specified as Yes, True, 1, and No, False, 0, and are case
insensitive. This file is automatically created by the installation
script if it does not exist, and neither does the symbolic link
/vmlinuz. The script asks the user whether the symbolic link should be
created, and stashes the answer into /etc/kernel-img.conf
At the moment, the user modifiable variables supported are:
link_in_boot
Set to Yes if you want the symbolic link to the kernel image,
namely, vmlinuz in /boot rather than the default /. The old,
and very confusing, name image_in_boot is deprecated, since it
is the symbolic link that is usually being relocated. Defaults
to No.
do_symlinks
By default, the kernel image post installation script shall
create or update the /vmlinuz and /vmlinuz.old symbolic links.
This is true if a /vmlinuz link already exists, however, in
absence of /vmlinuz, the script looks to see if this
configuration file exists. If it does not, the configuration
script asks the user whether to create the symbolic link, and
stashes the answer in a newly created /etc/kernel-img.conf. If
the configuration file already exists, and if this option is set
to No, no symbolic link is ever created. This for people who
have other means of booting their machines, and do not like the
symbolic links cluttering up their / directory. Defaults to
Yes.
minimal_swap
By default, if the /vmlinuz symbolic link does not point to an
image which is the same as the image being installed, the
postinst moves /vmlinuz to /vmlinuz.old, and creates a symbolic
link to the kernel image in /vmlinuz (the exception is to
prevent both /vmlinuz and /vmlinuz.old from pointing to the
current kernel image -- potentially disastrous if the current
image is defective or lacking in any way). However, if this
option is enabled, no action is taken if /vmlinuz.old points to
the currently installed image (by default, the symbolic links
are swapped). Defaults to no.
no_symlinks
Whether to use symlinks to the image file. Mutually exclusive
to reverse_symlinks. Can be used with link_in_boot
(image_in_boot). If set to Yes, the real image is placed in
vmlinuz (instead of /boot/vmlinuz-X.X.XX). If you use
link_in_boot in conjunction with this, /boot/vmlinuz-X.X.XX is
moved to /boot/vmlinuz. The old vmlinuz is moved to vmlinuz.old
unconditionally. (Normally, that is only done if the version of
the new image differs from the old one). This restricts you to
two images, unless you take additional action and save copies of
older images. This is for people who have /boot on a system that
does not use symbolic links (and say, they use loadlin as a
bootloader). This is a Hack. Defaults to No.
reverse_symlinks
Whether to use reverse symlinks (that is, the real file is the
one without the version number, and the number version is the
link) to the image file. Mutually exclusive to no_symlinks.
Can be used with link_in_boot (image_in_boot). Just like
no_symlinks, except that the /boot/vmlinuz-X.XX is a symbolic
link to the real new image, vmlinuz. This, too, restricts you to
just two images unless further action is taken. The older
symlinks are left dangling. This is for people with /boot on
umsdos, and who can’t see the link in dos, but do want to know
the image version when in Linux. This is a Hack. Defaults to
No.
image_dest
If you want the symbolic link (or image, if move_image is set)
to be stored elsewhere than / set this variable to the dir where
you want the symbolic link. Please note that this is not a
boolean variable. This may be of help to loadlin users, who may
set both this and move_image Defaults to /. This can be used in
conjunction with all above options except link_in_boot
(image_in_boot), which would not make sense. (If both image_dest
and link_in_boot (image_in_boot) are set, link_in_boot
(image_in_boot) overrides)
postinst_hook
Set this variable to a script to be executed during installation
after all the symbolic links are created, but before running the
bootloader or offering to create a floppy. This script shall be
called with two arguments, the first being the version of the
kernel image, and the second argument being the location of the
kernel image itself. Errors in the script shall produce a
warning message, but shall be otherwise ignored. An example
script for grub users is present in
/usr/share/doc/kernel-package/ directory.
postrm_hook
Set this variable to a script to be executed in the postrm (that
is, after the image has been removed) after all the remove
actions have been performed. This script shall be called with
two arguments, the first being the version of the kernel image,
and the second argument being the location of the kernel image
itself. Errors in the script shall produce a warning message,
but shall be otherwise ignored.
preinst_hook
Set this variable to a script to be executed before the package
is unpacked, and can be used to put in additional checks. This
script shall be called with two arguments, the first being the
version of the kernel image, and the second argument being the
location of the kernel image itself.
prerm_hook
Set this variable to a script to be executed before the package
files are removed (so any added files may be removed) . This
script shall be called with two arguments, the first being the
version of the kernel image, and the second argument being the
location of the kernel image itself. Errors in the script shall
produce a warning message, but shall be otherwise ignored.
ramdisk
Set this variable to a executable that creates an initial RAM
disk. This only has any effect if installing a kernel-image that
uses an initail RAM disk. The command so pointed must be drop-in
compatible with mkinitrd.
src_postinst_hook
Unlike the other hook variables, this is meant for a script run
during the post inst of a docs, headers or a source package.
Using this hook for the headers package is now being deprecated,
at some point the headers post install script shall only run the
header_postinst_hook. This script shall be called with two
arguments, the first being the name of the package being
installed (could be kernel-source-X.X.XX or
kernel-headers-X.X.XX), and the second argument being the
version of the package being installed. Errors in the script
shall produce a warning message, but shall be otherwise ignored.
headers_postinst_hook
Unlike the other hook variables, this is meant for a script run
during the post inst of a headers package only. This script
shall be called with two arguments, the first being the name of
the package being installed (kernel-headers-X.X.XX), and the
second argument being the version of the package being
installed. Errors in the script shall produce a warning message,
but shall be otherwise ignored.
move_image
Instead of creating symbolic links to (or, if reverse_symlinks
is set, from) image_dest, the image is moved from its location
in /boot into image_dest. If reverse_symlinks is set, /boot
shall contain a symbolic link to the actual image. This option
can be useful to people using loadlin, who may need the image to
be moved to a different, dos partition. This variable is unset
by default.
clobber_modules
If set, the preinst shall silently try to move
/lib/modules/version out of the way if it is the same version as
the image being installed. Use at your own risk. This variable
is unset by default.
do_boot_enable
If set to NO, this short circuits all attempts to create boot
floppies, run lilo, etc. This has the additional side effect
that the postinst is silent. Setting both do_bootfloppy and
do_bootloader to NO implies setting do_boot_enable to NO.
Defaults to Yes.
do_bootfloppy
If set to NO, this prevents the postinst from asking questions
about creating a boot floppy. and no boot floppy is created. The
bootloader shall still be run. This may cut down on the
interaction the postinst has. (It still prompts before
formatting /dev/fd0) Defaults to Yes.
do_bootloader
If set to NO, this prevents the postinst from running the boot
loader. The user may still be asked to create a floppy, unless
do_bootfloppy is also set to NO. Defaults to Yes.
relative_links
If set to yes, the kernel image postinst script shall go to
extra ordinary lengths to ensure that the symbolic links are
relative. Normally, the symbolic links are relative when it is
easily determinable that relative links shall work. Defaults to
No.
do_initrd
Set to YES to prevent the kernel-image post installation script
from issueing a warning when installing an initrd kernel. This
assumes you have correctly set up your boot loader to be able to
boot the initrd image. Default: no. This is deprecated in favour
of the more descriptive warn_initrd option (please note that the
sense of the option is inverted).
warn_initrd
Set to NO to prevent the kernel-image post installation script
from issueing a warning when installing an initrd kernel. This
assumes you have correctly set up your boot loader to be able to
boot the initrd image. This is now preferred to do_initrd, since
warnings are what are prevented. Default: YES
use_hard_links
This option has been put in for the people who can’t handle
symbolic links (a boot loader that does not handle symbolic
links, for example). If set to YES, this shall cause the kernel
image postinst to use hard link instead of symbolic links for
the automatically handled /vmlinuz and /vmlinuz.old. I have
tried to make it compatible with move_image and reverse_symlinks
Caveat: It is up to the end user to ensure that the image_dest
directory and the location of the image (nominally /boot) live
on the same file system (since one can’t make hard links across
file systems). You have been warned.
relink_build_link
This option manipulates the build link created by recent
kernels. If the link is a dangling link, and if a the
corresponding kernel-headers appear to have been installed on
the system, a new symlink shall be created to point to them. The
default is to relink the build link (YES).
force_build_link
This option manipulates the build link created by recent
kernels. If the link is a dangling link, a new symlink shall be
created to point to /usr/src/kernel-headers-X.Y.ZZ, whether they
have been installed or not. The default is unset, we don’t
create potentially dangling symlinks by default.
relink_source_link
This option manipulates the source link created by recent
kernels. If the link is a dangling link it is deleted at install
time. The default is to relink (delete) the source link (YES).
mkimage
This should be a command that produces an initrd image given a
directory. It is passed to the mkinitrd program’s -m option. For
example, it can be
mkimage="genromfs -d %s -f %s" or
mkimage="mkcramfs %s %s"
silent_modules
This option has been put in for the people who are vastly
irritated on being warned about preexisting modules directory
/lib/modules/$version That directory may belong to an old or
defunct kernel-image-$version package, in which case problems
may arise with leftover modules in that dir tree, or the
directory may legitimately exist due to a independent modules
package being installed for this kernel version that has already
been unpacked. In this latter case the existence of the
directory is benign. If you set this varable, you shall no
longer be given a chance to abort if a preexisting modules
directory /lib/modules/$version is detected. This is unset be
default.
silent_loader
If set, this option shall cause the question asked before
running the boot laoder in the installation process to be
skipped. Whether or not the boot loader is run is unaffected by
this option ( see do_bootloader to see how to control whether
the boot loader is run or not, and the absense of the
configuration file will also make the install process voluble
and interactive).
ignore_depmod_err
If set, does not prompt to continue after a depmod problem in
the postinstall script. This facilitates automated installs,
though it may mask a problem with the kernel image. A diagnostic
is still issued.
FILES
The file described here is /etc/kernel-img.conf.
SEE ALSO
make-kpkg(1), kernel-pkg.conf(5), 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.