Linux Kernel Compile

1. Compile

1.1. Clean

• make clean : Deletes most files generated during build except the .config file. The .config file is the config file used in previous kernel compilation.
• make mrproper : Deletes all files generated during build including the .config file and config-related backup files.
• make distclean : Performs mrproper and additionally deletes editor backup files and patch files.

1.2. Configuration

• make config : Sets config in a question-and-answer format.
• make menuconfig : Sets config using an Ncurses (Text)-based GUI. When using a config file from a previous kernel version, if additional settings are needed, they are set to default values.
• make xconfig : Sets config using a QT (X-Window)-based GUI. When using a config file from a previous kernel version, if additional settings are needed, they are set to default values.
• make oldconfig : Uses an existing .config file. When using a config file from a previous kernel version, if additional settings are needed, it asks the user for configuration methods in a question-and-answer format.

1.3. Build

• make zImage : Compiles the kernel and creates a compressed zImage file.
• make uImage : Creates a zImage file and then creates a uImage file used by u-boot. The mkimage tool must be installed. On Ubuntu, install the uboot-mkimage package.
• make modules : Compiles modules.

1.4. Install

• make install : Creates an initrd image, copies vmlinuz and System.map files to /boot, creates symbolic links, and modifies grub.conf appropriately so that it can boot with the new kernel image.
• make modules_install : Stores compiled modules in the $INSTALL_MOD_PATH/lib/modules/[kernel version] folder. You can change the copy location by setting the $INSTALL_MOD_PATH variable in the shell. If $INSTALL_MOD_PATH is not set, they are copied under the lib folder of /(root).

1.5. E.T.C

• make tags : Creates ctags files.
• make cscope : Creates cscope files.
• make help : Shows make targets and descriptions.

2. Example

2.1. ARM

$ ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- make menuconfig
$ ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- make zImage
$ ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- make uImage
$ ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- make modules
$ ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- INSTALL_MOD_PATH=tmp make modules_install