Re: Inserting code from userspace to kernel space

[Alex Belits <abelits@phobos.illtel.denver.co.us>]

On Thu, 22 May 2008, Bosko Radivojevic wrote:

> I'm looking for a way to insert code from user space to the kernel
> space, but without using kernel module. Actually, we are working on a
> system that has to allow end user to change part of code (one or two
> functions) that is executed from the kernel space.
>
> For now we have two different kernel modules, one exporting a function
> which another module uses. Process of compiling kernel module is quite
> ineligible for standard end user (along with the requirement to
> support multi platform cross compiling) compared to just cross
> compiling a simple code that doesn't use any libraries than libc.

Why? You don't have to recompile everything, just link a module before 
loaing it -- a part containing the function can be one object file, the 
rest of the module (a wrapper) is compiled once for a particular kernel 
version, and both are linked together, producing a module valid for a 
particular kenel version.

This is how most of proprietary drivers are distributed, and Ubuntu has a 
whole infrastructure around that mechanism that simplifies transition 
between versions.

-- 
Alex