Building Linux Packages For Kernel Drivers! (dkms howto)
Background
Most of the time the Linux kernel does a great job of having drivers you need, but sometimes you need to install a special driver or update an existing module.
Running make; make install is all fine and dandy for testing, but for production you want a repeatable process. For me, this means OS packages. (deb/rpms)
So, how do you go from kernel module source code => Debian package? DKMS. DKMS will automatically build your kernel module for you, even if your kernel gets updated.
Example: ixgbe
Lets build something. In this example I’m on an Ubuntu machine building the latest ixgbe driver.
- Get apt-get your stuff
apt-get install debhelper dkms kernel-headers
- Untar your source code into /usr/src/$modulename-$version, like /usr/src/ixgbe-3.12.6/
- Normally here you would run “make”, but instead we will make a dkms.conf file to describe how to build it. Like this:
MAKE="make -C src/ KERNELDIR=/lib/modules/${kernelver}/build"
CLEAN="make -C src/ clean"
BUILT_MODULE_NAME=ixgbe
BUILT_MODULE_LOCATION=src/
DEST_MODULE_LOCATION="/updates"
PACKAGE_NAME=ixgbe-dkms
PACKAGE_VERSION=3.12.6
REMAKE_INITRD=no
- Next we need to register that module with dkms:
root@server:/usr/src/ixgbe-3.12.6# dkms add -m ixgbe -v 3.12.6
Creating symlink /var/lib/dkms/ixgbe/3.12.6/source ->
/usr/src/ixgbe-3.12.6
DKMS: add completed.
- Next we will build the module, but using the dkms build command instead of make:
root@server:/usr/src/ixgbe-3.12.6# dkms build -m ixgbe -v 3.12.6
Kernel preparation unnecessary for this kernel. Skipping...
Building module:
cleaning build area....
make KERNELRELEASE=3.2.0-23-generic -C src/ KERNELDIR=/lib/modules/3.2.0-23-generic/build....................
cleaning build area....
DKMS: build completed.
- Great! Next we will make a debian src package.
root@server:/usr/src/ixgbe-3.12.6# dkms mkdsc -m ixgbe -v 3.12.6 --source-only
Using /etc/dkms/template-dkms-mkdsc
copying template...
modifying debian/changelog...
modifying debian/compat...
modifying debian/control...
modifying debian/copyright...
modifying debian/dirs...
modifying debian/postinst...
modifying debian/prerm...
modifying debian/README.Debian...
modifying debian/rules...
copying legacy postinstall template...
Copying source tree...
Building source package... dpkg-source --before-build ixgbe-dkms-3.12.6
debian/rules clean
dpkg-source -b ixgbe-dkms-3.12.6
dpkg-source: warning: no source format specified in debian/source/format, see dpkg-source(1)
dpkg-genchanges -S >../ixgbe-dkms_3.12.6_source.changes
dpkg-genchanges: including full source code in upload
dpkg-source --after-build ixgbe-dkms-3.12.6
DKMS: mkdsc completed.
Moving built files to /var/lib/dkms/ixgbe/3.12.6/dsc...
Cleaning up temporary files...
- Now we will build the “binary” debian package. In reality with –source-only this binary package just contains the source code in the module with a post install script to build the module for each kernel you are using. Its magic:
root@server:/usr/src/ixgbe-3.12.6# dkms mkdeb -m ixgbe -v 3.12.6 --source-only
Using /etc/dkms/template-dkms-mkdeb
copying template...
modifying debian/changelog...
modifying debian/compat...
modifying debian/control...
modifying debian/copyright...
modifying debian/dirs...
modifying debian/postinst...
modifying debian/prerm...
modifying debian/README.Debian...
modifying debian/rules...
copying legacy postinstall template...
Copying source tree...
Building binary package...dpkg-buildpackage: warning: using a gain-root-command while being root
dpkg-source --before-build ixgbe-dkms-3.12.6
fakeroot debian/rules clean
debian/rules build
fakeroot debian/rules binary
dpkg-genchanges -b >../ixgbe-dkms_3.12.6_amd64.changes
dpkg-genchanges: binary-only upload - not including any source code
dpkg-source --after-build ixgbe-dkms-3.12.6
DKMS: mkdeb completed.
Moving built files to /var/lib/dkms/ixgbe/3.12.6/deb...
Cleaning up temporary files...
- We have a deb! Lets put it in ~
root@server:/usr/src/ixgbe-3.12.6# cp /var/lib/dkms/ixgbe/3.12.6/deb/ixgbe-dkms_3.12.6_all.deb ~
- So we have a deb. I would like to install it, but we have to get rid of the build files so they will not conflict with the deb we just built:
root@server:/usr/src/ixgbe-3.12.6# rm -r /var/lib/dkms/ixgbe/
- Now we have a deb that you can install locally, distribute wherever, install across a cluster:
root@server:/usr/src/ixgbe-3.12.6# dpkg -i /root/ixgbe-dkms_3.12.6_all.deb
Selecting previously unselected package ixgbe-dkms.
(Reading database ... 56500 files and directories currently installed.)
Unpacking ixgbe-dkms (from .../root/ixgbe-dkms_3.12.6_all.deb) ...
Setting up ixgbe-dkms (3.12.6) ...
Loading new ixgbe-3.12.6 DKMS files...
First Installation: checking all kernels...
Building only for 3.2.0-23-generic
Building for architecture x86_64
Building initial module for 3.2.0-23-generic
Done.
ixgbe:
Running module version sanity check.
- Original module
- Installation
- Installing to /lib/modules/3.2.0-23-generic/updates/dkms/
depmod....
DKMS: install completed.
