DKMS(8)DKMS(8)NAMEdkms - Dynamic Kernel Module Support
SYNOPSISdkms [action] [options]
DESCRIPTIONdkms is a framework which allows kernel modules to be dynamically built
for each kernel on your system in a simplified and organized fashion.
ACTIONS
add Adds a module/version combination to the tree for builds and
installs. Requires source in /usr/src/<module>-<module-ver‐
sion>/ as well as a properly formatted dkms.conf file.
remove Removes a module/version or module/version/kernel combination
from the tree. If the modules is currently installed, it first
uninstalls it and if applicable, will replace it with its origi‐
nal_module. Use the --all option in order to remove all
instances for every kernel at once.
build Builds the specified module/version combo for the specified ker‐
nel. If no kernel is specified it builds for the currently run‐
ning kernel. All builds occur in the directory
/var/lib/dkms/<module>/<module-version>/build/.
install
Installs a built module/version combo onto the kernel it was
built for. If the kernel option is not specified it assumes the
currently running kernel.
uninstall
Uninstalls an installed module/version combo from the kernel it
was installed upon. After uninstall completion, the driver will
be left in the built state. To completely remove a driver, the
remove action should be utilized.
match Match installs modules onto the specified kernel by looking at
the configuration of the specified templatekernel. Every module
that is installed on the templatekernel within dkms is then
installed on that specified kernel.
mkdriverdisk
Creates a floppy driver disk image for use when updated drivers
are needed to install an OS. Currently, the supported distribu‐
tions are redhat, suse and UnitedLinux. For Red Hat driver
disks, necessary driver disk files are looked for in the red‐
hat_driver_disk subdirectory of your module source directory.
You must specify the distro while using this action. Driver
disks can be made for single kernels or can be made to support
multiple kernels. To create a driver disk image with modules
for multiple kernels, just specify multiple -k parameters on the
command line (-k kernel1 -k kernel2 -a arch1 -a arch2).
Red Hat began supporting multi-arched driver disks in RHEL3. To
force creation of a driver disk with arch information, specify
-d redhat2 or if you specify multiple architectures on the com‐
mand-line and use -d redhat , DKMS will create a version 2
driver disk. By specifying -d redhat1 , you can force a version
1 driver disk image.
Note that redhat1 driver disks actually supported multiple
architectures when the second arch was i386 and the kernel mod‐
ule was for the BOOT kernel. DKMS allows for this, and as such
you can create a redhat1 style driver disk if the only other
arch is i386 and the kernel name ends in BOOT.
See http://people.redhat.com/dledford for more information on
the Red Hat driver disk standards and which files are necessary
to make a driver disk.
Fedora Core 5 and higher, RHEL5 and higher require DKMS version
2.0.14 or higher to generate a proper driver disk image.
For suse/UnitedLinux driver disks, /usr/share/YaST2/modules/Ven‐
dor.ycp will also be copied to the driver disk; no other files
are needed. However, for these distros, you must specify a -r
release. For SuSE 9.1, it would be -d suse -r 9.1. For SLES9, it
would be -d suse -r sles9.
By default the disk image it creates is 1440 (k) in size. This
can be overridden by specifying a different --size #### which
should should be given as a number in kilobytes divisible by 20.
You may have more content than will fit on a floppy. Therefore,
DKMS can now generate image files of different types.
--media=floppy (default) to generate a floppy disk image, or
--media=iso to generate a CD-ROM ISO file, or --media=tar to
generate a tar file.
You may copy the floppy or ISO image file to a USB key to be
used with OS installer.
mktarball
Creates a tarball archive for the specified module/version of
all files in the DKMS tree for that module/version combination.
This includes the source and any built modules for kernels in
the tree (as specified). Otherwise, you can specify a singular
kernel to archive only, or multiple kernels to archive (-k ker‐
nel1 -k kernel2 -a arch1 -a arch2). Optionally, you can use
--archive to specify the name (with no preceding path) that you
would like this tarball to have. You can also specify --bina‐
ries-only if you want the resultant tarball not to include the
module source. Likewise, --source-only can be used to specify
that no prebuilt binaries should be included in the tarball. In
general, mktarball is great for systems management purposes as
you can build your driver on just one system and then use ldtar‐
ball on all of your other systems to get the same built modules
loaded without having to wait for anything to compile.
ldtarball
This takes a tarball made from the mktarball command and speci‐
fied with the --archive option and loads it into your DKMS tree.
This will leave any newly added modules in the built state and
dkms install should then be called to install any of them. If
files already exist where ldtarball is attempting to place them,
it will warn and not copy over them. The --force option should
be used to override this.
mkrpm This action allows you to create an RPM package for a specified
module / version. It uses a template .spec file found in
/etc/dkms/template-dkms-mkrpm.spec as the basis for the RPM.
Alternatively, if DKMS finds a file called /usr/src/<mod‐
ule>-<module-version>/<module>-dkms-mkrpm.spec it will use that
.spec file instead. In general, a DKMS tarball is placed inside
the contents of this RPM, and the RPM itself calls various DKMS
commands to load this tarball, build and install modules on the
end user's system. If you do not want your RPM to contain any
prebuilt binaries, be sure to specify --source-only in the mkrpm
command.
mkdeb This action allows you to create a debian package for a speci‐
fied module / version. It uses a template debian directory
found in /etc/dkms/template-dkms-mkdeb as the basis for the
package. Alternatively, if DKMS finds a file called
/usr/src/<module>-<module-version>/<module>-dkms-mkdeb it will
use that folder instead. In general, a DKMS tarball is placed
inside the contents of this package, and the package itself
calls various DKMS commands to load this tarball, build and
install modules on the end user's system. If you do not want
your debian package to contain any prebuilt binaries, be sure to
specify --source-only in the mkdeb command.
mkkmp This action allows you to create an Kernel Module Package source
RPM for a specified module / version. It uses the .spec file
specified by --spec=specfile else $module-kmp.spec as the basis
for the RPM. The generated source RPM may then be built using
SuSE's build.rpm or Fedora/RHEL's mock chroot environments. See
http://kerneldrivers.org/ for more details on KMPs.
status Returns the current status of modules, versions and kernels
within the tree as well as whether they have been added, built
or installed. Status can be shown for just a certain module, a
certain kernel, a module/version combination or a module/ver‐
sion/kernel combination.
OPTIONS-m <module>
The name of the module.
-v <module-version>
The version of the module to execute the specified action upon.
-k <kernel-version>
The kernel to perform the action upon. You can specify multiple
kernel versions on the command line by repeating the -k argument
with a different kernel name. However, not all actions support
multiple kernel versions (it will error out in this case).
-a, --arch
The system architecture to perform the action upon. If not
specified, it assumes the arch of the currently running system
(`uname -m`). You can specify multiple arch parameters on the
same command line by repeating the -a argument with a different
arch name. When multiple architectures are specified, there
must be a 1:1 relationship between -k arguments to -a arguments.
DKMS will then assume the first -a argument aligns with the
first -k kernel and so on for the second, third, etc.
For example, if you were to specify: -k kernel1 -k kernel2 -a
i386 -k kernel3 -a i686 -a x86_64, DKMS would process this as:
kernel1-i386, kernel2-i686, kernel3-x86_64.
-q, --quiet
Quiet.
-V, --version
Prints the currently installed version of dkms and exits.
-c <dkms.conf-location>
The location of the dkms.conf file. This is needed for the add
action and if not specified, it is assumed to be located in
/usr/src/<module>-<module-version>/. See below for more infor‐
mation on the format of dkms.conf.
-d, --distro
The distribution being used. This is only currently needed for
mkdriverdisk. The supported distros are redhat, suse and Unit‐
edLinux. See the sections on mkdriverdisk and mkkmp for more
information.
-r, --release
The release being used. This is only currently used for
mkdriverdisk and is only used for suse or UnitedLinux distros
(eg. -r 9.1). It is used in the internal makeup of the
driverdisk.
--size The size of the driver disk image to be created. By default,
this value is set at 1440. Any different size should be given
as an integer value only, should be divisible by 20 and should
represent the number of kilobytes of the image size you desire.
--config <kernel-.config-location>
During a build this option is used to specify an alternate loca‐
tion for the kernel .config file which was used to compile that
kernel. Normally, dkms uses the Red Hat standard location and
config filenames located in /usr/src/linux-<kernel>/configs/.
If the config for the kernel that you are building a module for
is not located here or does not have the expected name in this
location, you will need to tell dkms where the necessary .config
can be found so that your kernel can be properly prepared for
the module build.
--archive <tarball-location>
This option is used during a ldtarball action to specify the
location of the tarball you wish to load into your DKMS tree.
--templatekernel <kernel-version>
This option is required for the action: match. Match will look
at the templatekernel specified and install all of the same mod‐
ule/version combinations on the other kernel.
--force
This option can be used in conjunction with ldtarball to force
copying over of already existant files.
--binaries-only
This option can be used in conjunction with mktarball in order
to create a DKMS tarball which does not contain the source for
the module within it. This can be helpful in reducing the size
of the tarball if you know that the system which this tarball
will be loaded upon already has the source installed. In order
to load a tarball made as binaries-only you must have the module
source in that systems DKMS tree. If you do not, DKMS will
refuse to load a binaries-only tarball.
--source-only
This option can be used in conjunction with mktarball or mkrpm
or mkdeb in order to create a DKMS tarball which does not con‐
tain any prebuilt kernel module binaries within it. This is
helpful if you simply want to easily tar up your source but
don't want anything prebuilt within it. Likewise, if you are
using mkrpm but do not want the RPM you create to have any pre‐
built modules within it, passing this option will keep its
internal DKMS tarball from containing any prebuilt modules.
--all This option can be used to automatically specify all relevant
kernels/arches for a module/module-version. This is useful for
things like remove , mktarball , etc. This saves the trouble of
having to actually specify -k kernel1 -a arch1 -k kernel2 -a
arch2 for every kernel you have built your module for.
--no-prepare-kernel
This option keeps DKMS from first preparing your kernel before
building a module for it. Generally, this option should not be
used so as to ensure that modules are compiled correctly.
--no-clean-kernel
This option keeps DKMS from cleaning your kernel devel tree
after a build.
--kernelsourcedir <kernel-source-directory-location>
Using this option you can specify the location of your kernel
devel directory. Most likely you will not need to set this if
your kernel source is accessible via /lib/modules/$kernel_ver‐
sion/build.
--directive <"cli-directive=cli-value">
Using this option, you can specify additional directives from
the command line. The --directive option can be used multiple
times on the same command-line to specify multiple additional
command line directives.
--rpm_safe_upgrade
This flag should be used when packaging DKMS enabled modules in
RPMs. It should be specified during both the add and remove
actions in the RPM spec to ensure that DKMS and RPM behave cor‐
rectly in all scenarios when upgrading between various versions
of a dkms enabled module RPM package. See the sample.spec file
for an example or read more in the section below on Creating
RPMs Which Utilize DKMS.
--spec specfile
This option is used by the mkkmp action to specify which RPM
spec file to use when generating the KMP. specfile will be
sought in the module source directory.
ORIGINAL MODULES
During the first install of a module for a <kernelversion>, dkms will
search /lib/modules/<kernelversion> for a pre-existing module of the
same name. If one is found, it will automatically be saved as an "orig‐
inal_module" so that if the newer module is later removed, dkms will
put the original module back in its place. Currently, DKMS searches
for these original modules with first preference going to modules
located in /lib/modules/<kernelversion>/updates/ followed by $DEST_MOD‐
ULE_LOCATION (as specified in dkms.conf ). If one cannot be found in
either location, a find will be used to locate one for that kernel. If
none are found, then during a later uninstall, your kernel will not
have that module replaced.
If more than one is found, then the first one located (by preference
indicated above) will be considered the "original_module". As well,
all copies of the same-named module will be removed from your kernel
tree and placed into /var/lib/dkms/<module>/original_module/$ker‐
nelver/collisions so that they can be *manually* accessible later. DKMS
will never actually do anything with the modules found underneath the
/collisions directory, and they will be stored there until you manually
delete them.
DKMS.CONF
When performing an add , a proper dkms.conf file must be found. A
properly formatted conf file is essential for communicating to dkms how
and where the module should be installed. While not all the directives
are required, providing as many as possible helps to limit any ambigu‐
ity. Note that the dkms.conf is really only a shell-script of variable
definitions which are then sourced in by the dkms executable (of the
format, DIRECTIVE="directive text goes here"). As well, the directives
are case-sensitive and should be given in ALL CAPS.
It is important to understand that many of the DKMS directives are
arrays whose index values are tied together. These array associations
can be considered families, and there are currently four such families
of directive arrays. MAKE[#] and MAKE_MATCH[#] make up one family.
PATCH[#] and PATCH_MATCH[#] make up the second family. The third and
largest family consists of BUILT_MODULE_NAME[#], BUILT_MODULE_LOCA‐
TION[#], DEST_MODULE_NAME[#], DEST_MODULE_LOCATION[#], MOD‐
ULES_CONF_ALIAS_TYPE[#], MODULES_CONF_OBSOLETES[#], MODULES_CONF_OBSO‐
LETE_ONLY[#] and STRIP[#]. The fourth family is made up of only MOD‐
ULES_CONF[#]. When indexing these arrays when creating your dkms.conf,
each family should start at index value 0.
MAKE[#]=
The MAKE directive array tells DKMS which make command should be
used for building your module. The default make command should
be put into MAKE[0]. Other entries in the MAKE array will only
be used if their corresponding entry in MAKE_MATCH[#] matches,
as a regular expression (using egrep), the kernel that the mod‐
ule is being built for. Note that if no value is placed in
MAKE_MATCH[#] for any MAKE[#] where # > 0, then that MAKE direc‐
tive is ignored. MAKE_MATCH[0] is optional and if it is popu‐
lated, it will be used to determine if MAKE[0] should be used to
build the module for that kernel. If multiple MAKE_MATCH direc‐
tives match against the kernel being built for, the last match‐
ing MAKE[#] will be used to build your module. If no MAKE direc‐
tive is specified or if no MAKE_MATCH matches the kernel being
built for, DKMS will attempt to use a generic MAKE command to
build your module.
MAKE_MATCH[#]=
See the above entry on MAKE[#] directives. This array should be
populated with regular expressions which, when matched against
the kernel being built for, will tell DKMS to use the corre‐
sponding make command in the MAKE[#] directive array to build
your module.
BUILT_MODULE_NAME[#]=
This directive gives the name of the module just after it is
built. If your DKMS module package contains more than one mod‐
ule to install, this is a required directive for all of the mod‐
ules. This directive should explicitly not contain any trailing
".o" or ".ko". Note that for each module within a dkms package,
the numeric value of # must be the same for each of BUILT_MOD‐
ULE_NAME, BUILT_MODULE_LOCATION, DEST_MODULE_NAME and DEST_MOD‐
ULE_LOCATION and that the numbering should start at 0 (eg.
BUILT_MODULE_NAME[0]="qla2200" BUILT_MODULE_NAME[1]="qla2300").
BUILT_MODULE_LOCATION[#]=
This directive tells DKMS where to find your built module after
it has been built. This pathname should be given relative to
the root directory of your source files (where your dkms.conf
file can be found). If unset, DKMS expects to find your
BUILT_MODULE_NAME[#] in the root directory of your source files.
Note that for each module within a dkms package, the numeric
value of # must be the same for each of BUILT_MODULE_NAME,
BUILT_MODULE_LOCATION, DEST_MODULE_NAME and DEST_MODULE_LOCATION
and that the numbering should start at 0 (eg. BUILT_MODULE_LOCA‐
TION[0]="some/dir/" BUILT_MODULE_LOCATION[1]="other/dir/").
DEST_MODULE_NAME[#]=
This directive can be used to specify the name of the module as
it should be installed. This will rename the module from
BUILT_MODULE_NAME[#] to DEST_MODULE_NAME[#]. This directive
should explicitly not contain any trailing ".o" or ".ko". If
unset, it is assumed to be the same value as BUILT_MOD‐
ULE_NAME[#]. Note that for each module within a dkms package,
the numeric value of # must be the same for each of BUILT_MOD‐
ULE_NAME, BUILT_MODULE_LOCATION, DEST_MODULE_NAME and DEST_MOD‐
ULE_LOCATION and that the numbering should start at 0 (eg.
DEST_MODULE_NAME[0]="qla2200_6x" DEST_MOD‐
ULE_NAME[1]="qla2300_6x").
DEST_MODULE_LOCATION[#]=
This directive specifies the destination where a module should
be installed to, once compiled. It also is used for finding
original_modules. This is a required directive. This directive
must start with the text "/kernel" which is in reference to
/lib/modules/<kernelversion>/kernel. Note that for each module
within a dkms package, the numeric value of # must be the same
for each of BUILT_MODULE_NAME, BUILT_MODULE_LOCATION, DEST_MOD‐
ULE_NAME and DEST_MODULE_LOCATION and that the numbering should
start at 0 (eg. DEST_MODULE_LOCATION[0]="/kernel/drivers/some‐
thing/" DEST_MODULE_LOCATION[1]="/kernel/drivers/other/").
MODULES_CONF_ALIAS_TYPE[#]=
This directive array specifies how your modules should be
aliased in /etc/modules.conf when your module is installed.
This is done in an intelligent fashion so if DKMS detects an
already existing reference in modules.conf, it won't add a new
line. If it is not detected, it will add it to the modules.conf
as the last alias number for that alias type (eg. if MOD‐
ULES_CONF_ALIAS_TYPE="scsi_hostadapter", no alias currently
exists for that module and the last scsi_hostadapter reference
is 6, then your module will be added as "scsi_hostadapter7").
Common values for this directive include: scsi_hostadapter ,
sound-slot- and eth. Note that the numeric value of # is tied
to the index of BUILD_MODULE_NAME, BUILT_MODULE_LOCATION,
DEST_MODULE_NAME and DEST_MODULE_LOCATION. The index is also
tied to MODULES_CONF_OBSOLETES.
MODULES_CONF_OBSOLETES[#]=
This directive array tells DKMS what modules.conf alias refer‐
ences are obsoleted by the module you are installing. If your
module obsoletes more than one module, this directive should be
a comma-delimited list of those modules that are obsoleted (eg.
for megaraid2, MODULES_CONF_OBSO‐
LETES[0]="megaraid,megaraid_2002"). When you are installing your
module, DKMS ensures that any entries in /etc/modules.conf with
the same MODULES_CONF_ALIAS_TYPE are changed over to the new
module name. When you are uninstalling your module, depending
on the modules in your /lib/modules tree, DKMS will take differ‐
ent actions. If you kernel has an original_module, then mod‐
ules.conf will not be touched and the non-obsolete reference
will remain. If the kernel does not have an original_module but
does have one of the obsolete modules, it will replace those
references with the first obsolete module name in the comma-
delimited list that is also in that kernel (thus, your obsolete
list should be prioritized from left to right). If no origi‐
nal_module or obsolete modules are found within the kernel, the
alias entry is removed all-together. Note that the numeric value
of # is tied to the index of BUILD_MODULE_NAME, BUILT_MOD‐
ULE_LOCATION, DEST_MODULE_NAME and DEST_MODULE_LOCATION. The
index is also tied to MODULES_CONF_ALIAS_TYPE.
MODULES_CONF_OBSOLETE_ONLY[#]=
If set to yes , this directive will tell DKMS to only modify
/etc/modules.conf if it finds within it an obsolete reference as
specified in the corresponding value of MODULES_CONF_OBSO‐
LETES[#] array directive.
STRIP[#]=
By default strip is considered to be "yes". If set to "no",
DKMS will not run strip -g against your built module to remove
debug symbols from it.
PACKAGE_NAME=
This directive is used to give the name associated with the
entire package of modules. This is the same name that is used
with the -m option when building, adding, etc. and may not nec‐
essarily be the same as the MODULE_NAME. This directive must be
present in every dkms.conf.
PACKAGE_VERSION=
This directive is used to give the version associated with the
entire package of modules being installed within that dkms pack‐
age. This directive must be present in every dkms.conf.
CLEAN= CLEAN specifies the make clean command to be used to clean up
both before and after building the module. If unset, it is
assumed to be "make clean".
REMAKE_INITRD=
This directive specifies whether your initrd should be remade
after the module is installed onto the kernel. Any text after
the first character is ignored and if the first character is not
a "y" or a "Y", it is assumed that REMAKE_INITRD="no".
MODULES_CONF[#]=
This directive array specifies what static configuration text
lines need to be added into /etc/modules.conf for your module.
See the section on MODULES.CONF CHANGES for more information
regarding the implications of modifying /etc/modules.conf
PATCH[#]=
Use the PATCH directive array to specify patches which should be
applied to your source before a build occurs. All patches are
expected to be in -p1 format and are applied with the patch -p1
command. Each directive should specify the filename of the
patch to apply, and all patches must be located in the patches
subdirectory of your source directory ( /usr/src/<module>-<mod‐
ule-version>/patches/ ). If any patch fails to apply, the build
will be halted and the rejections can be inspected in
/var/lib/dkms/<module>/<module-version>/build/. If a PATCH
should only be applied conditionally, the PATCH_MATCH[#] array
should be used, and a corresponding regular expression should be
placed in PATCH_MATCH[#] which will alert dkms to only use that
PATCH[#] if the regular expression matches the kernel which the
module is currently being built for.
PATCH_MATCH[#]=
See the above description for PATCH[#] directives. If you only
want a patch applied in certain scenarios, the PATCH_MATCH array
should be utilized by giving a regular expression which matches
the kernels you intend the corresponding PATCH[#] to be applied
to before building that module.
AUTOINSTALL=
If this directive is set to yes then the service
/etc/rc.d/init.d/dkms will automatically try to install this
module on any kernel you boot into. See the section on
dkms_autoinstaller for more information.
BUILD_EXCLUSIVE_KERNEL=
This optional directive allows you to specify a regular expres‐
sion which defines the subset of kernels which DKMS is allowed
to build your module for. If the kernel being built for does
not match against this regular expression, the dkms build will
error out. For example, if you set it as ="^2.4.*", your module
would not be built for 2.6 kernels.
BUILD_EXCLUSIVE_ARCH=
This optional directive functions very similarly to BUILD_EXCLU‐
SIVE_KERNEL except that it matches against the kernel architec‐
ture. For example, if you set it to ="i.86", your module would
not be built for ia32e, x86_64, amd64, s390, etc.
POST_ADD=
The name of the script to be run after an add is performed. The
path should be given relative to the root directory of your
source.
POST_BUILD=
The name of the script to be run after a build is performed. The
path should be given relative to the root directory of your
source.
POST_INSTALL=
The name of the script to be run after an install is performed.
The path should be given relative to the root directory of your
source.
POST_REMOVE=
The name of the script to be run after a remove is performed.
The path should be given relative to the root directory of your
source.
PRE_BUILD=
The name of the script to be run before a build is performed.
The path should be given relative to the root directory of your
source.
PRE_INSTALL=
The name of the script to be run before an install is performed.
The path should be given relative to the root directory of your
source. If the script exits with a non-zero value, the install
will be aborted. This is typically used to perform a custom
version comparison.
DKMS.CONF VARIABLES
Within your dkms.conf file, you can use certain variables which
will be replaced at run-time with their values.
$kernelver
This variable can be used within a directive definition and dur‐
ing use, the actual kernel version in question will be substi‐
tuted in its place. This is especially useful in MAKE commands
when specifying which INCLUDE statements should be used when
compiling your module (eg. MAKE="make all INCLUDEDIR=/lib/mod‐
ules/${kernelver}/build/include").
$dkms_tree
See the section on /etc/dkms/framework.conf for more informa‐
tion. This variable represents the location of the DKMS tree on
the local system. By default this is /var/lib/dkms , but this
value should not be hard-coded into a dkms.conf in the event
that the local user has changed it on their system.
$source_tree
See the section on /etc/dkms/framework.conf for more informa‐
tion. This variable represents the location where DKMS keeps
source on the local system. By default this is /usr/src , but
this value should not be hard-coded into a dkms.conf in the
event that the local user has changed it on their system.
$kernel_source_dir
This variable holds the value of the location of your kernel
devel directory. Usually, this will be /lib/modules/$ker‐
nelver/build , unless otherwise specified with the --kernel‐
sourcedir option.
/etc/dkms/framework.conf
This configuration file controls how the overall DKMS framework han‐
dles. It is sourced in everytime the dkms command is run. Mainly it
can currently be used to set different default values for the variables
$dkms_tree , $source_tree and $install_tree which control where DKMS
looks for its framework. Note that these variables can also be manipu‐
lated on the command line with the undocumented --dkmstree, --source‐
tree and --installtree options. Whoops, did I just document these?
dkms_autoinstaller
This boot-time service automatically installs any module which has
AUTOINSTALL="yes" set in its dkms.conf file. The service works quite
simply and if multiple versions of a module are in your system's DKMS
tree, it will not do anything and instead explain that manual interven‐
tion is required.
MODULES.CONF / MODPROBE.CONF CHANGES
Changes that your module will make to /etc/modules.conf or /etc/mod‐
probe.conf should be specified with the MODULES_CONF_ALIAS_TYPE[#] ,
the MODULES_CONF_OBSOLETES[#] and the MODULES_CONF[#] directive arrays.
These arrays should also be used even if your distro uses /etc/syscon‐
fig/kernel to track kernel modules.
When the first module is installed upon the first kernel within the
user's system, these entries in MODULES_CONF[#] are automatically added
to /etc/modules.conf and if REMAKE_INITRD is specified, then the user's
initrd is then remade. Subsequently, as your modules are then later
removed from the user's system, until the final module/version combina‐
tion is removed from the final kernel version, those references in mod‐
ules.conf will remain. Once the last module/version combination is
removed, those references are then removed.
As modules/versions are removed and initrds are remade, one of three
things will happen if you have specified a MODULES_CONF_ALIAS_TYPE. If
no original_module exists for that kernel, and no MODULES_CONF_OBSO‐
LETES modules are found in that kernel too, the modules.conf alias ref‐
erences will temporarily be removed so that the initrd will success‐
fully remake. Once the initrd is remade, however; those references are
then automatically put back into modules.conf (unless you are removing
the last instance of the module on the last kernel). However, if no
original_module exists, but there is an OBSOLETE module found within
that kernel, the alias reference is temporarily shifted to point to the
OBSOLETE module so that the initrd can be remade. After it is remade,
it then automatically puts back the alias reference (unless you are
removing the last instance of the module on the last kernel). Lastly,
if an original_module does exist for the kernel version, then mod‐
ules.conf is not touched and all references persist (even if you are
removing the last instance of the module on the last kernel).
Certain module installations might not only require adding references
to modules.conf but also require removing conflicting references that
might exist in the user's system. If this is the case, the MOD‐
ULES_CONF_OBSOLETES[#] directive should be utilized to remove these
references. More information about this directive can be found in the
DKMS.CONF section of this man page.
Note that the end state of your modules.conf file very much depends on
what kernel modules exist in the final kernel you remove your DKMS mod‐
ule from. This is an imperfect system caused by the fact that there is
only one modules.conf file for every kernel on your system even though
various kernels use different modules. In a perfect world, there would
be one modules.conf file for every kernel (just like System.map).
CREATING RPMS WHICH UTILIZE DKMS
See the sample.spec file packaged with DKMS as an example for what your
RPM spec file might look like. Creating RPMs which utilize dkms is a
fairly straight-forward process. The RPM need only to install the
source into /usr/src/<module>-<module-version>/ and then employ dkms
itself to do all the work of installation. As such, the RPM should
first untar the source into this directory. From here, within the RPM
.spec file, a dkms add should be called (remember to use the
--rpm_safe_upgrade flag during the add) followed by a dkms build fol‐
lowed by a dkms install. Your dkms.conf file should be placed within
the /usr/src/<module>-<module-version>/ directory.
Under the removal parts of the .spec file, all that needs to be called
is a: dkms remove -m <module> -v <module-version> --all
--rpm_safe_upgrade.
Use of the --rpm_safe_upgrade flag is imperative for making sure DKMS
and RPM play nicely together in all scenarios of using the -Uvh flag
with RPM to upgrade dkms enabled packages. It will only function if
used during both the add and remove actions within the same RPM spec
file. Its use makes sure that when upgrading between different releases
of an RPM for the same <module-version>, DKMS does not do anything dumb
(eg. it ensures a smooth upgrade from megaraid-2.09-5.noarch.rpm to
megaraid-2.09-6.noarch.rpm).
It should be noted that a binary RPM which contains source is not a
traditional practice. However, given the benefits of dkms it hopefully
will become so. As the RPM created which utilizes dkms is not archi‐
tecture specific, BuildArch: noarch should be specified in the .spec
file to indicate that the package can work regardless of the system
architecture. Also note that DKMS RPM upgrades (-U option) will auto‐
matically work because of the structure of the dkms tree.
Lastly, as a matter of convention, you should name your RPM: <pack‐
age>-<version>-<rpm-version>dkms.noarch.rpm. The word dkms as part of
the rpm-version signifies that the RPM works within the DKMS framework.
AUTHOR
Gary Lerhaupt
WEBPAGE
http://linux.dell.com/dkms
WHITE-PAPERS
http://linux.dell.com/dkms/dkms-ols2004.pdf
http://www.dell.com/downloads/global/power/1q04-ler.pdf
http://www.linuxjournal.com/article.php?sid=6896
MAILING-LIST
dkms-devel@dell.com http://lists.us.dell.com/mailman/listinfo/dkms-
devel
REFERENCES
Kernel Module Packages http://kerneldrivers.org
Novell Kernel Module Packages http://www.suse.de/~agruen/KMPM
Fedora Kernel Module Packages http://fedoraproject.org/wiki/Extras/Ker‐
nelModuleProposal
Version 2.0.14 Feb 2007 DKMS(8)
