Why would someone want to compile a new kernel? It is often not necessary since the default kernel shipped with Debian handles most configurations. Also, Debian often offers several alternative kernels. So you may want to check first if there is an alternative kernel image package that better corresponds to your hardware. However, it can be useful to compile a new kernel in order to:
handle special hardware needs, or hardware conflicts with the pre-supplied kernels
use options of the kernel which are not supported in the pre-supplied kernels (such as high memory support)
optimize the kernel by removing useless drivers to speed up boot time
create a monolithic instead of a modularized kernel
kør en opdateret eller udviklingskerne
lær mere om Linuxkerner
Vær ikke bange for at prøve at kompilere kernen. Det er sjovt og giver indsigt.
To compile a kernel the Debian way, you need some packages: fakeroot
, kernel-package
, linux-source-2.6
and a few others which are probably already installed (see /usr/share/doc/kernel-package/README.gz
for the complete list).
This method will make a .deb of your kernel source, and, if you have non-standard modules, make a synchronized dependent .deb of those too. It's a better way to manage kernel images; /boot
will hold the kernel, the System.map, and a log of the active config file for the build.
Note that you don't have to compile your kernel the “Debian way”; but we find that using the packaging system to manage your kernel is actually safer and easier. In fact, you can get your kernel sources right from Linus instead of linux-source-2.6
, yet still use the kernel-package
compilation method.
Bemærk at du kan finde en fuldstændig dokumentation for brugen af kernel-package
under /usr/share/doc/kernel-package
. Dette afsnit indeholder kun en kort introduktion.
Hereafter, we'll assume you have free rein over your machine and will extract your kernel source to somewhere in your home directory[22]. We'll also assume that your kernel version is 3.16. Make sure you are in the directory to where you want to unpack the kernel sources, extract them using tar xf /usr/src/linux-source-3.16.tar.xz
and change to the directory linux-source-3.16
that will have been created.
Now, you can configure your kernel. Run make xconfig
if X11 is installed, configured and being run; run make menuconfig
otherwise (you'll need libncurses5-dev
installed). Take the time to read the online help and choose carefully. When in doubt, it is typically better to include the device driver (the software which manages hardware peripherals, such as Ethernet cards, SCSI controllers, and so on) you are unsure about. Be careful: other options, not related to a specific hardware, should be left at the default value if you do not understand them. Do not forget to select “Kernel module loader” in “Loadable module support” (it is not selected by default). If not included, your Debian installation will experience problems.
Clean the source tree and reset the kernel-package
parameters. To do that, do make-kpkg clean
.
Now, compile the kernel: fakeroot make-kpkg --initrd --revision=1.0.custom kernel_image
. The version number of “1.0” can be changed at will; this is just a version number that you will use to track your kernel builds. Likewise, you can put any word you like in place of “custom” (e.g., a host name). Kernel compilation may take quite a while, depending on the power of your machine.
Once the compilation is complete, you can install your custom kernel like any package. As root, do dpkg -i ../linux-image-3.16-
. The subarchitecture
_1.0.custom_amd64.debsubarchitecture
part is an optional sub-architecture, depending on what kernel options you set. dpkg -i
will install the kernel, along with some other nice supporting files. For instance, the System.map
will be properly installed (helpful for debugging kernel problems), and /boot/config-3.16
will be installed, containing your current configuration set. Your new kernel package is also clever enough to automatically update your boot loader to use the new kernel. If you have created a modules package, you'll need to install that package as well.
Det er tid til at genstarte systemet: Læs omhyggeligt alle advarsler som de ovenstående trin kan have medført, og så shutdown -r now
.
For more information on Debian kernels and kernel compilation, see the Debian Linux Kernel Handbook. For more information on kernel-package
, read the fine documentation in /usr/share/doc/kernel-package
.
[22] There are other locations where you can extract kernel sources and build your custom kernel, but this is easiest as it does not require special permissions.