Ubuntu replaces the specified version of the kernel

background

An error is reported when the Linux block device driver is compiled under the kernel version 5.15. So there are two ways:

1. Modify driver code to accommodate version changes
2. Switch to a lower version kernel

The first method is too low for me to choose,
so I had to change to a lower version of the kernel, but I encountered many problems when I thought of it.

Replace the specified kernel

Concrete operation: Concrete operation

Take version 5.4.0 as an example

	wget https://raw.githubusercontent.com/pimlie/ubuntu-mainline-kernel.sh/master/ubuntu-mainline-kernel.sh
	chmod +x ubuntu-mainline-kernel.sh
	sudo mv ubuntu-mainline-kernel.sh /usr/local/bin/

search and find your wanted version

	ubuntu-mainline-kernel.sh -r | grep 5.4

install that version kernel

	ubuntu-mainline-kernel.sh -i v5.4.0

update grub

	update-grub

reboot

	reboot now

verify

	uname -r

Failed, the 22.04 release version installed the 5.4 version of the kernel, it seems that it does not work.

When I search for the kernel using the following command, I can only see versions 5.15 and 5.17. After I forcibly downloaded the 5.4.0 version of the kernel, I could choose to replace the kernel after restarting, but I couldn't enter the system. So I had to give up.

`apt-cache search linux-image-`

After reflecting on it, I still don't have a deep understanding of the linux kernel version and release version. Version 5.4 is the kernel used on Ubuntu 20.04, and version 5.15 is used on Ubuntu 22.04. The modification of the kernel in different release versions is definitely different, so when I forcibly installed the 5.4 version on the 22.04 version of Ubuntu, the system could not start at all.

Try Ubuntu 20.04

• Download the iso file and set the root password

• Install enhanced functions to realize file and pasteboard sharing
  Directly install enhanced functions, and then restart the virtual machine

• Configure Tsinghua mirror source
  switch to root, download vim

  su -

  apt-get vim
  

  backup source

  	cp /etc/apt/sources.list /etc/apt/sources.list.bak
  

  manual substitution or command substitution

  vim /etc/apt/sources.list
  

  Go to the mirror source website to find the replacement list

  renew

  apt-get update
  

try changing the kernel again

This time on the 20.04 version of Ubuntu, you can find a lot of 5.4 version kernels.

This time I try version 5.4.75

ubuntu-mainline-kernel.sh -i v5.4.75

Modify the grub file to select the kernel when booting

vim /etc/default/grub

Change to:

	GRUB_HIDDEN_TIMEOUT=10
	#GRUB_STYLE_HIDDEN

update-grub

update-grub

Restart to verify

Select the newly installed version 5.4.75 kernel

Check the current version, it has been successfully replaced.

uname -r

Install the development tools, recompile the block driver

After replacing the kernel, the virtual machine enhancement function is still invalid. It still does not work after removing the VboxGuest disk and reinstalling it again.
forget it

sudo apt-get install build-essential #安装开发工具包，包含gcc等

install headers

uname -rCheck the current kernel version

apt search linux-headerFind all header versions of the software library

sudo apt-get install linux-headers-XXX-X-amd6install header

Install a range of kernel environments

  sudo apt-get install kernel-package 
   #测试中会出现缺这缺那的情况，如以下包会丢失，如编译源码出现错误，可尝试执行
   sudo apt-get install flex bison 
   #和/或
   sudo apt-get install libssl-dev
   #和/或
   sudo apt-get install libelf-dev #libelf-devel or elfutils-libelf-devel
   #如仍未解决，可自行搜索或尝试解决方案
   
   #编译生成menuconfig配置内核界面所需文件（非必须）
   sudo apt-get install libncurses5-dev
   
   #开发版本管理及自动化包
   sudo apt-get install automake#此处可能会有版本号
   sudo apt-get install autoconf cvs subversion

Start compiling the driver sbull

Enter the sbull folder, make

The compilation was successful in one fell swoop, and it seems that it is indeed a problem with the kernel version.

Install the module: insmod sbull.ko

dmesg view log

View module information: lsmod

See sbull

to view block device information: fdisk -l /dev/sbulla

Format block device: mkfs.ext4 /dev/sbulla

It says Filesystem too small for a journal, I don’t know how to

mount and use the block device. After mounting and using the block device, you


can use this device to view the loading results like other hard disks

: mount

to view the usage

You can see that the count has changed to 1

Enter the device to create a file

Remount after unmounting

It was found that the data disappeared after uninstalling, but after remounting, the data was restored.

unmount disk

Unmount /mnt/sbull. After waiting for more than 30 seconds, when trying to mount the /dev/sbulla device again, the system prompts that the partition type on the block device must be specified. Indicates that the device has been formatted.

unload kernel module