Ubuntu Wiki
The majority of users that are interested in building their own kernel are doing so because they have installed Ubuntu on their system and they wish to make a small change to the kernel for that system. In many cases the user just wants to make a kernel configuration change.
The purpose of this page is to give that user a minimum amount of information for them to meet the goal of making a simple change to the kernel, building it and installing their kernel. It is not intended to be the definitive guide to doing Ubuntu kernel development.
Build Environment
sudo apt-get build-dep linux linux-image-$(uname -r)
sudo apt-get install libncurses-dev gawk flex bison openssl libssl-dev dkms libelf-dev libudev-dev libpci-dev libiberty-dev autoconf llvm
deb-src http://archive.ubuntu.com/ubuntu disco main deb-src http://archive.ubuntu.com/ubuntu disco-updates main
Obtaining the source for an Ubuntu release
There are a number of different ways of getting the kernel sources. The two main ways will be documented here.
If you have installed a version of Ubuntu and you want to make changes to the kernel that is installed on your system, use the apt-get method (described below) to obtain the sources.
However, if you wish to get the most up to date sources for the Ubuntu release you are running and make changes to that, use the git method (described below) to obtain the sources.
apt-get
apt-get source linux-image-unsigned-$(uname -r)
git
git clone git://kernel.ubuntu.com/ubuntu/ubuntu-.git
git clone git://kernel.ubuntu.com/ubuntu/ubuntu-disco.git
Modifying the configuration
chmod a+x debian/rules chmod a+x debian/scripts/* chmod a+x debian/scripts/misc/* LANG=C fakeroot debian/rules clean LANG=C fakeroot debian/rules editconfigs # you need to go through each (Y, Exit, Y, Exit..) or get a complaint about config later
This takes the current configuration for each architecture/flavour supported and calls menuconfig to edit its config file. The chmod is needed because the way the source package is created, it loses the executable bits on the scripts.
In order to make your kernel «newer» than the stock Ubuntu kernel from which you are based you should add a local version modifier. Add something like «+test1» to the end of the first version number in the debian.master/changelog file, before building. This will help identify your kernel when running as it also appears in uname -a. Note that when a new Ubuntu kernel is released that will be newer than your kernel (which needs regenerating), so care is needed when upgrading. NOTE: do not attempt to use CONFIG_LOCALVERSION as this _will_ break the build.
Building the kernel
LANG=C fakeroot debian/rules clean # quicker build: LANG=C fakeroot debian/rules binary-headers binary-generic binary-perarch # if you need linux-tools or lowlatency kernel, run instead: LANG=C fakeroot debian/rules binary
cd .. ls *.deb linux-headers-4.8.0-17_4.8.0-17.19_all.deb linux-headers-4.8.0-17-generic_4.8.0-17.19_amd64.deb linux-image-4.8.0-17-generic_4.8.0-17.19_amd64.deb
on later releases you will also find a linux-extra- package which you should also install if present.
Testing the new kernel
sudo dpkg -i linux*4.8.0-17.19*.deb sudo reboot
Debug Symbols
sudo apt-get install pkg-config-dbgsym LANG=C fakeroot debian/rules clean LANG=C fakeroot debian/rules binary-headers binary-generic binary-perarch skipdbg=false
See also
Kernel Git Guide | More information about using git to pull down the kernel sources. |
ARM Cross Compile | For more info about ARM and cross compilation. |
Kernel/BuildYourOwnKernel (последним исправлял пользователь b-stolk 2022-09-08 00:38:14)
The material on this wiki is available under a free license, see Copyright / License for details.
How do I get the kernel source code?
I am planning to write some device drivers and I need to get the Linux kernel source. My Linux kernel version is 3.2.0-23-generic-pae and I downloaded the image from this. In many of the articles I have read, it tells me that I need to have the entire kernel tree to start inserting new modules. Is it enough if I download this image and paste it into the usr/src/ folder or do I have to do something else?
I usually just install the ‘linux-source’ package from synaptic when I’m custom compiling for one of my machines, but given you’re doing development you might need the most recent version. This link might be useful to you: help.ubuntu.com/community/Kernel/Compile
5 Answers 5
This will get the source of the stock kernel:
apt-get source linux-source
You can check what version of the kernel is running like this:
Which will print something like:
You can find a list of current source package versions available on your system via:
apt-cache search linux-source
To get the upstream version of the kernel:
git clone git://kernel.ubuntu.com/ubuntu/ubuntu-trusty.git
In the above link, ‘trusty’ is the codename for the version of Ubuntu. You can find out the codename for the version of Ubuntu you have installed via:
If I use git to clone how do i specify the version. Also If i Clone it is it enough if a I copy pate it into the usr/src folder
That git repository is kept to 3.2.0 specifically; it follows what’s in Ubuntu Precise (12.04). If you want a different version change ubuntu-precise.git to ubuntu-quantal.git or whatever. It should be fine to just copy into usr/src.
And where should I be able to find the source tree when installing with. Damn, I should read better. The answer says apt-get source not apt-get install . Than the source tree will end up in your current path.
sudo apt install linux-source # downloads into system directory sudo apt source linux-source # downloads into working directory
If you’re told to give some ‘sources’ URLs in your sources.list , go edit your /etc/apt/sources.list file and uncomment the desired deb-src line, for example (if you’re running Xenial):
deb http://fr.archive.ubuntu.com/ubuntu/ xenial main restricted # deb-src http://fr.archive.ubuntu.com/ubuntu/ xenial main restricted
Removing the # on this last line enables sources repositories for download, including kernel sources.
- Use modern tools; avoid apt-get .
- These commands download the source code for your current kernel (in my case 4.4.0-75-generic for example).
- When downloaded into system directory, files are stored in /usr/src/linux-source-4.4.0/ (for example).
Doesn’t work for me (but neither does the apt-get version). I’m running Ubuntu 16.04.4, kernel 4.4.0-98-generic. It says, «You must put some ‘source’ URIs in your sources.list». I have no idea how to do that.
Yes thanks. It was a stupid comment from me. I only needed to google the error message. Anyway, have an upvote for your effort.
is the easiest way. It will download the source from your repository — and it’ll be the same as the version you’re running (assuming you haven’t already customised it).
But if you want to find where the source is maintained you can run:
Look for the ‘Vcs-‘ attribute (Version control system). It’ll usually be a git (Vcs-Git) or mercurial repository.
Note — these commands work with any package. Just substitute ‘linux’ with the package you’re interested in. And also note that ‘apt-get source’ doesn’t need sudo access and will dump the source in your current directory.
This requires the machine you are downloading on to match the target machine. Really only works if you have a network. Most of the readers landing on this page won’t have a network (hence why they suddenly need the source). I need it as a tarball on a thumb drive and I don’t have a working apt.
This downloading the src into the CURRENT DIRECTORY on Ubuntu 20.04 LTS, but it downloaded the wrong version of the kernel?? linux-5.4.0 when uname -r = 5.8.0-55-generic
Download source directly from Launchpad
Strangely enough everyone recommends apt-get source which doesn’t work most of the time if you’re looking for a specific kernel version:
Say you need kernel source for 3.19.0-58 :
apt-get source linux-image-3.19.0-58-generic will get the source for the latest kernel in the series: 3.19.0-80 in this case, which is not what you asked for.
1) Give up, install kernel 3.19.0-80 and use apt-get source
2) Get source directly from launchpad:
- Google site:launchpad.net «linux-image-3.19.0-58-generic»
- That should give you the Launchpad Package Page for that version.
- Scroll down, click the «Source:» link, you’re on the Package Source Page now.
- Scroll down and download .tar.gz , .diff.gz , .dsc files:
- There must be a better way.
- You can get the version you want from git, but you’re in for a big download. See «Obtaining the kernel sources for an Ubuntu release using git» in Ubuntu Wiki Kernel Source Code.
Thank you for explaining this so clearly. However, I am still unable to find the source for linux-image-4.15.0-39-generic. This process is needlessly complicated. I’ve tried googling for it but I keep finding packages that are a few kilobytes only. Any tips?
This is the only option on this page that worked for Ubuntu 20.04 LTS to get something that claims to be a similar kernel version linux-5.8.0 to the one returned but uname -r
There are cases where it is simply more practical to download the linux kernel source and headers for the version you’re interested in directly from http://kernel.org (a pretty reliable URL/site that isn’t going away [e.g. standard stackoverflow concern about stale links isn’t not an issue])
Reason? For example, you might be interested in debugging an older/defunct no-longer-supported version of linux where package repository points to dead areas, where in some cases there are either no viable current alternatives, or the repos has are expired keys that won’t let you get the stuff, requiring unmemorable difficult to search out arcane techniques to get those repositories to work anyway.
Or maybe Internet networking might be broken on Linux machine (or VM) you’re using, but file sharing or NFS works, where the source can be downloaded onto another machine and accessed via the filesystem.
If you’re working with a relatively obsolete version of Linux, chances are you’ll have to build a number of things from source and get them the hard way.