Comments on: How to compile a kernel for Ubuntu Karmic

By: goro4111

goro4111 — Sun, 14 Feb 2010 10:43:11 +0000

Thanks for the detailed well structured HOWTO. It actually helped me a lot to start compiling the kernel form my old pc.

I must say that I followed all the step, several times, and I do not see any problem with the steps themselves, but I have a problem with booting up with the kernel I made.

After I compile my kernel (2.6.31-20.57) and install it, I reboot and grub will default choose the new kernel (perfect). The boot process stop when the following error is received:
udevd [xx]: segfult …. error 6 in libc.so.6 Segmentation fault

I tried the compilation several times, but still with no luck. Would you please guide me if I’m missing anything or whether the new version (20.57) is not compatible with this description.

Note: I’m changing the configuration of the kernel with quite few things:
- Select the Configure standard kernel features (for small systems) from General Setup
- Disable Power management AND ACPI options
- Disable DMA engine support form Device Drivers
- Disable some of the Ubuntu supplied third-party device drivers

Once again, thanks for the super blog, and one more thanks for helping me.

By: The process of compile a new kernel » Paul's blog

The process of compile a new kernel » Paul's blog — Sat, 13 Feb 2010 23:11:57 +0000

[...] to actually see if this is a issue, iam currently busy compiling a new kernel, like described here. To enable the toshiba functions, I need to set a option under Processor type and features -> [...]

By: Saint DanBert

Saint DanBert — Fri, 12 Feb 2010 23:20:30 +0000

I really want to do this and REALLY enjoyed the read. As usually, I have questions:

1. There is list of drivers and modules (lsmod &c) that get used on my hardware. What is a good way to create a reasonably complete list so that I don’t break something I use? How do I make sure that I have all of the various parts and
back ports and extras and whatever so that everything get built completely and correctly?

2. Is there a good roadmap to help match kernel config parameters with my own hardware and operational requirements?

Thanks,
~~~ 0;-Dan

By: Peter

Peter — Fri, 12 Feb 2010 19:38:57 +0000

You don’t have to use sudo for the su command, but in Ubuntu direct login as root is disabled (no password is set for the root user making it impossible to login in). When you type su -, you ask to login directly as root and as mentioned, this is disabled by default.

su –> login as root
sudo –> run as root

So by running sudo su -, you basically trick the system, you run su as root and the systems says, ok you are root so no need to ask for a password. To show this try the following:
Open a terminal as a normal user and run su – you will be prompted for a password. Now become root and run su – no password is required.

Using sudo -i brings environment variables DISPLAY and TERM into the root shell from the user that executes the command and adds the environment variables SUDO_USER and SUDO_UID. In general that is not that big of deal, in our case we could use sudo -i instead of sudo su -.

By: Saint DanBert

Saint DanBert — Fri, 12 Feb 2010 18:32:58 +0000

I notice that you type “sudo su -” before you perform a series of apt-get commands The “su -” uses set -user to start a login shell ( ‘-’ ) as superuser. This is redundant on a couple of levels. First, one does not to be super user to run “su”.
Using “sudo -i” uses the super-user-do command as an interactive shell ( ‘-i’ ). Likewise, “sudo -b” runs the command as a background task.Check out the sudo man-page for details.

If there is a difference between “su -” and “sudo -i” I have not found any operational reason. I prefer and recommend “sudo -” because there is logging whereas “su -” has none.

Another man’s thoughts,
~~~ 0;-Dan

By: Peter

Peter — Sun, 07 Feb 2010 18:12:02 +0000

If you want to change the configuration I do believe you’ll have to compile the kernel all over again.
By recompiling you won’t have conflicts, what you could do to keep track of your configurations is make backups of every configuration under a different name.

By: Chris

Chris — Sun, 07 Feb 2010 02:05:43 +0000

Thank you for this good article. I was able to compile my own kernel with your help.

How would be the workflow for compiling several versions of the kernel with different configurations? I want to change the configuration frequently (for finding out what’s good and what is not) without recompiling everything and without conflicts in the package manager or elsewhere. Would be nice if you could help me with that.

By: Thai

Thai — Tue, 26 Jan 2010 03:10:27 +0000

After reading this post, I started compiling my own kernel. Unfortunately, I did the compilation on a 900MB disk and found out that 900MB is not enough.

I have aCore2Duo T6570 cpu. Could those who finished the compilation and have a core2duo please let me and others know if you can see any significant performance improvement on your systems?

By: Wim Vervoorn

Wim Vervoorn — Fri, 22 Jan 2010 10:15:20 +0000

Forget about this. It was a mistake that occurred somewhere in the configuration. The control file is created correctly now!

By: Wim Vervoorn

Wim Vervoorn — Thu, 21 Jan 2010 10:45:31 +0000

Hello,

For some reason I get the error :

“dh_installchangelogs : package linux-image……. is not in control info” when executing the fakeroot debian/rules binary-core2 command in your description.

I check the debian/control to see if there is any reference to “linux-image…..” in there but there isn’t. I verified the changes in getabis and i386.mk and the changes are there.

Do you have any suggestions of what could have gone wrong and where to look for the problem?

Thanks in advance.

Wim