Arch Linux

Ranguvar

Member

Registered: 2008-08-12

Posts: 2,563

Custom kernel + Arch stock kernel = joy... how?

Hello,

I am now attempting to create the perfect kernel upgrade system But, I need a little help.

A basic custom kernel would work, I think, by editing the PKGBUILD after an ABS sync - removing the 'yes "" | make config' line, and replacing it with 'make menuconfig'. But, that's not perfect

My perfect system would be:

1.) New kernel arrives in Arch core.
2.) I ABS sync and edit.
3.) A diff is made from the old default config to the new default config, and presented to review. This should really help finding potential pitfalls with my own config.
4.) 'make menuconfig' - I load my old custom config, and then edit if necessary.
5.) The kernel is created, same as usual. BUT, no fallback kernel is made.
6.) The kernel is made again, this time with the default config. It is NOT installed to the normal spot, but is instead used to create the fallback image only.

This way, I'm sure to have a working backup kernel.

Some of this stuff I can do, but I'm really not sure about other parts, especially step 5/6.

Help would be much appreciated

klixon

Member

From: Nederland

Registered: 2007-01-17

Posts: 525

Re: Custom kernel + Arch stock kernel = joy... how?

Here's what i usually do (except on major version bumps):
1. Boot the kernel you use now.
2. unpack new kernel-source and enter the build-directory
3.

zcat /proc/config.gz > .config && make oldconfig

This keeps your old config mostly intact and asks about changes/new things in the config.

After that i still usually do a make menuconfig

This requires in your kernel-config:
CONFIG_IKCONFIG=y
CONFIG_IKCONFIG_PROC=y

(set them in "General Setup/{"Kernel .config support", "Enable access to .config through /proc/config.gz"}

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Stand back, intruder, or i'll blast you out of space! I am Klixon and I don't want any dealings with you human lifeforms. I'm a cyborg!

Ranguvar

Member

Registered: 2008-08-12

Posts: 2,563

Re: Custom kernel + Arch stock kernel = joy... how?

OK, thanks, that may help

Heller_Barde

Member

Registered: 2008-04-01

Posts: 245

Re: Custom kernel + Arch stock kernel = joy... how?

actually with the stock kernel there are not two kernels made, only two ramdisks. I would advise you to create your own pkgbuild which installs all the stuff but with some sort of own suffix (like vmlinuz26 <-> vmlinuz26myownkernel).
there are 1-2 howtos in the wiki ("custom kernel compilation")
so i would advise you to have the stock kernel just as is, and just edit your /boot/grub/menu.lst to point to your custom kernel per default.

cheers Barde

methuselah

Member

Registered: 2007-10-02

Posts: 570

Re: Custom kernel + Arch stock kernel = joy... how?

A good way to compare files is the gnome app called "meld".

I use it to compare my different .config files to see what has been added or taken out of different kernel versions and patches.

big_gie

Member

Registered: 2005-01-19

Posts: 637

Re: Custom kernel + Arch stock kernel = joy... how?

I have made some small modifications to Arch's stock kernel26's PKGBUILD to ease the process of compiling a custom kernel.

Basically, all you need to do is to change the pkgname of the abs obtained PKGBUILD with a different name. For example, you could change it to:
pkgname=kernel26-myown
and you will end up with a "kernel26-myown-2.6.[...].pkg.tar.gz" package that can be installed side by side with the original one. You can then test new kernels easily.

The patch is avaible here:
http://bbs.archlinux.org/viewtopic.php?pid=282844

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