> I'm trying to replace the sys_fork() from the sys_call_table[] in 2.4.17
> with a verbatim implementation of it that also maintains process
> hierarchy information to be used later on for gang-scheduling. I'd like
> to load a module in the kernel that will replace the sys call. The
> module compiles with no errors/warnings, but insmod complains when
> attempting to load:
>
> gang.o: unresolved symbol do_fork
> gang.o:
> Hint: You are trying to load a module without a GPL compatible license
> and it has unresolved symbols. Contact the module supplier for
> assistance, only they can help you.
>
> Is there a way I can resolve/import the symbol or is do_fork() not
> exported by the kernel at all, forcing me to recompile the kernel to
> include the functionality of the module?
>
> Would it be possible to simply call the sys_fork() function pointer I'm
> trying to replace, and still somehow get it's return value and append
> the functionality I need?
You don't want to do this as module except for testing (replacing syscalls
from modules is not particularly reliable - if two modules try, bad things
will happen). For testing purposes, just add do_fork to the list of exported
modules (there is a file full of EXPORT macro calls somewhere in kernel source).
--------------------------------------------------------------------------------
- Jan Hudec `Bulb' <bulb@ucw.cz>
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