Kernel module info

A few commands to help in checking and adjusting kernel module options: 

1. Display information about kernel module, including all options
   
   modinfo $KERNEL_MODULE
   
   
2. Display information about current value for each option
   
   for i (/sys/module/$KERNEL_MODULE/parameters/*) {\
     echo $(basename $i);\
     cat $i\
   }
   
   
3. Change kernel module option without restart (temporary)
   
   echo "$NEW_VALUE" > /sys/module/$KERNEL_MODULE/parameters/$OPTION
   
   
4. Load module with an option set to value
   insmod $PATH_TO_MODULE/$KERNEL_MODULE.ko\ $OPTION1=$VALUE1 \
   $OPTION2=$VALUE2
   
   
5. Ensure kernel module option is set during boot up with grub
1. Open /etc/default/grub
2. Add/edit following line
   GRUB_CMDLINE_LINUX='$KERNEL_MODULE.$OPTION=$VALUE'
   

Of course $KERNEL_MODULE, as well as all other strings with "$" at the beginning, has to be replaced by appropriate value.

In CRUX /etc/default/grub does not exist, so it has to be created.

 Useful links

• https://www.cyberciti.biz/tips/how-to-display-or-show-information-about-a-linux-kernel-module-or-drivers.html
• https://devarea.com/linux-kernel-development-kernel-module-parameters/
• https://www.howtoforge.com/tutorial/kernel-boot-parameter-edit/
• https://www.linuxsecrets.com/1455-adding-kernel-boot-parameters-using-grub-on-linux
  

Shell script to setup system with new kernel

 

This is a small script helping in setting up a new kernel. It copies files from the Linux kernel source directory and builds the matching initramfs file.

 

#!/bin/sh
#
set -x
if [ $(dirname $PWD) != '/usr/src' ]
then
	echo ""
	echo "Please change directory to a one with Linux kernel sources"
	exit 1
fi

version=$(basename $PWD |awk -F\- '{print $2}')


ls boot/vmlinuz-${version}-* 2> /dev/null && \
	build=$(ls -1 /boot/vmlinuz-${version}-*| sort -n | awk -F\- '{print $3}') || \
	build=1

release=${version}-${build}
cp System.map /boot/System.map-${release}
cp arch/x86/boot/bzImage /boot/vmlinuz-${release}
mkinitrd /boot/initramfs-${release}.img ${version}

grub-mkconfig > /boot/grub/grub.cfg