Newbie: added function not visible

Newbie: added function not visible

[Genadz Batsyan]

I'm desperate, please help, if I'm missing something obvious.

I am trying to add a function to the file drivers/char/keyboard.c
and then be able to call this function from my kernel module

adding the function to keyboard.c, recompiling and booting with kernel
results  /proc/kallsyms telling me that my function exists with the tag 'T',
which I think is ok

In my module I simply declare the function's prototype and use it.

When trying to compile the module, modpost tells that the function's symbol
is not found. (insmodding results in error too)

I don't get it, WHY tha heck can it find all the other stuff and 
what makes this new function different? I have read that 2.6 kernel exports
any non-static symbols.

Regards!

Re: Newbie: added function not visible

[randy_dunlap]

On Wed, 29 Jun 2005 18:59:04 +0200 Genadz Batsyan wrote:

| I'm desperate, please help, if I'm missing something obvious.
| 
| I am trying to add a function to the file drivers/char/keyboard.c
| and then be able to call this function from my kernel module
| 
| adding the function to keyboard.c, recompiling and booting with kernel
| results  /proc/kallsyms telling me that my function exists with the tag 'T',
| which I think is ok

also add:
EXPORT_SYMBOL(new_symbol); /* whatever the new entry point is */

That makes it visible to modules.

| In my module I simply declare the function's prototype and use it.
| 
| When trying to compile the module, modpost tells that the function's symbol
| is not found. (insmodding results in error too)
| 
| I don't get it, WHY tha heck can it find all the other stuff and 
| what makes this new function different? I have read that 2.6 kernel exports
| any non-static symbols.


---
~Randy

Re: Newbie: added function not visible

[Robert Love]

On Wed, 2005-06-29 at 18:59 +0200, Genadz Batsyan wrote:

> adding the function to keyboard.c, recompiling and booting with kernel
> results  /proc/kallsyms telling me that my function exists with the tag 'T',
> which I think is ok

You need to EXPORT_SYMBOL your new function.

For example,

	/* My pet dog is an idiot */
	void beat_dog(struct dog *d)
	{
		/* ... */
	}
	EXPORT_SYMBOL(beat_dog);

Good luck,

	Robert Love