HowTo build a kernel

I write this article mainly to be able to remember all steps in a few months.

– Get kernel: git clone git://
This is the main kernel repository. Other repositories can be found at
For example the development of /dev/random takes place in git://

– As I don’t want to manually handle entries in grub, I want to use make-kpkg to build Debian packages.

– The package needs to be built as root, ‘–rootcmd fakeroot’ does not always work. Maybe there is some time to check this issue.

– Working with original sources instead of the Debian source package results in a plus sign added to the kernel version. This is done by one of the kernel scripts (scripts/setlocalversion)
For more info see comment at end of that script. I avoid this ‘+’ by doing something like: ‘export LOCALVERSION=”-ta-1″

– As /tmp nowadays is a bit small, you need to do somehting like ‘export TEMPDIR=/home/tmp’ or whatever suits your system

– Target ‘buildpackage’ calls ‘clean’ + ‘binary’
‘binary’ -> ‘binary-indep’ + ‘binary-arch’
‘binary-indep’ -> ‘kernel_source’, ‘kernel_manual’, ‘kernel_doc’
‘binary-arch’ -> ‘kernel_headers’, ‘kernel_image’

So for a normal builds, call ‘make-kpkg –initrd binary-arch’ or at least ‘make-kpkg –initrd kernel_image’

– In case of several cores call ‘make-kpkg -j 4 –initrd binary-arch’
(the blank between ‘j’ and ‘4’ is important)
The best results will be obtained if the given number equals the number of cores

– The old Laptop needs the following times to build the package:
make-kpkg –initrd binary-arch 91 minutes
make-kpkg -j 3 –initrd binary-arch 78 minutes
make-kpkg -j 4 –initrd binary-arch 59 minutes
make-kpkg -j 4 –initrd binary-arch &> log 57 minutes

– Check version of package in automatically build debian/changelog
The debian-directory can be rebuild by ‘make-kpkg debian’

– Move kernel package to Xen VM (grub-legacy should be installed, otherwise pygrub on wheezy dom0 is not able to start domU)
– dpkg -i
– edit /boot/grub/menu.lst (again a pygrub issue with some entries)