asm vs asm-generic in linux headers -- are they same

Question

In my linux header files folder on my Kali kernal 5.7.0 headers included in include directory /usr/src/linux-headers-5.7.0-kali1-common/include. Inside this folders I have header files contained in sub-folders like asm-generic,linux,uapi,acpi,crypto,etc.. But inside header files, i.e. inside linux/module.h there there is one header file reference included like

    #include <asm/module.h>  // top of linux/module.h

But Actually I don't have asm folder that got included with my header files when I installed them. So one solution that came to mind is. Probably solution: Change the references from asm/* to asm-generic/* as in from asm/module.h to asm-generic/module.h inside linux/module.h and other files which I may use. I like to know is asm and asm-generic are same? meaning they contains same files and structure or is there any difference i can cause problem

If I correct the directory name in include reference than Does it make sense, or I will get into problems when I compile the module if I change headers sub directories names in include list of header files from asm to asm-generic? If I dont do this the header files will be missing

Answer 1

Short answer

They are not the same.

kernel developer might include asm-generic headers in a asm header while asm headers are the headers required for kernel modules.

You may get more info from following post

• in linux kernel, asm or asm-generic?
• Linux kernel headers' organization
• linux module compilng missed folder asm

Take this question in another way.

It seems you're trying to make a kernel module.

To build a kernel module you need kernel-headers or compiled kernel source code. However I don't know kali linux, so I just provide generic suggestions here.

Where to get them

• Some of distributions, like Ubuntu, have prebuilt linux-headers.

  • Eg: Ubuntu has it in /usr/src/linux-headers-$(uname -r)/include

• Download it by sudo apt-get install linux-headers-$(uname -r)

  • It seems kali linux 2.0 might need more operations. Found this post might help.

• Build it yourself

  1. Checkout linux kernel code of your desired distro.
  2. Set up kernel config with make menuconfig ( You might get stumbled here a while.. many packages might be required )
  3. Compile kernel with make modules_prepare to compile essential Module.symvers for drivers. It take significant less time than compiling a full kernel.

I presume you already found a kernel module build example. If not, you may consult offical kernel module documentation. It helps a lot if you take a while to read first two chapters.

Or another example