[Linux-ia64] modules external refs

[Linux-ia64] modules external refs

[gerard]

I have a product consisting in several loadable modules,
among which one is the central controler.
When I load this on I do not have any problems, as it has external
references
only from the kernel.
But all the other modules call functions from this module.
I  started only with a module calling this controler.
I verified that in /proc/ksyms all the functions of the controler are
described.
I have put a printk in the second module trying to access the controler
in which I  print the address of the function it tries to call, it
corresponds to what
I see in /proc/ksyms, but when I call that function, I get a
Unimplemented Instruction Address fault .
I have tried to declare the function with a hardcoded address, and it
works "fine",
Iit seems that the external function reference is not resolved properly
when I load the module.
I do not have the version enabled in my environment.

What do I need to do to make it work, it used to work fine on a IA32
machine , but
not on a BIGSUR.
Thanks
Gerard LYONNAZ

Re: [Linux-ia64] modules external refs

[Keith Owens]

On Wed, 13 Jun 2001 17:04:51 +0200, 
gerard <gerard@mylos.grenoble.hp.com> wrote:
>I have put a printk in the second module trying to access the controler
>in which I  print the address of the function it tries to call, it
>corresponds to what
>I see in /proc/ksyms, but when I call that function, I get a
>Unimplemented Instruction Address fault .

IA64 function pointers do not point to the function, instead they point
to a descriptor area which contains data about the function, including
its real address.  If you are calling direct to the address in ksyms
then you are bypassing the function descriptor and r1 will contain an
incorrect value.  Also make sure that your modules are compiled with
the correct options, compile an existing module and copy the flags.