Modify Linux kernel config file

Question

How do I modify .config file in linux kernel?

When I type make device_defconfig a .config file is in created in the kernel directory. But when I type make menuconfig the .config file is modified. I would like to modify the <device>_defconfig in menuconfig.

score 6 · Accepted Answer · answered Dec 22 '19 at 20:42

6

The .config file is not generally supposed to be modified manually, event though you can.

The clean and simple way is:

make <device>_defconfig
make menuconfig
- edit
- exit saving changes
make savedefconfig
- creates a file named defconfig
cp defconfig arch/$ARCH/configs/<device>_defconfig
- where $ARCH is the CPU architecture, e.g. arm

A defconfig is similar to .config, except it contains only values that differ from their default values. As such they are much shorter and readable. The entire .config is very verbose but it's what make menuconfig edits and what the kernel needs to build.

answered Dec 22 '19 at 20:42

Luca Ceresoli

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1

thank you! one step is you might need to do `export ARCH=arm64` before the first step. – dazza5000 Apr 21 '20 at 13:51
1

@dazza5000 Sure, if you are cross-compiling then you need to set ARCH beforehand. – Luca Ceresoli Apr 21 '20 at 16:00

Modify Linux kernel config file

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