[OpenAFS-devel] Re: linux 2.6.x module version magic failure on SMP systems (FC2)

[Jeffrey Hutzelman]

On Tuesday, June 22, 2004 20:02:41 +0200 Rainer Sch=F6pf=20
<rainer.schoepf@proteosys.com> wrote:

> On Fri, 18 Jun 2004, Jeffrey Hutzelman wrote:
>
>  > Is this the module from the MP or SP directory?
>  > In theory they should be identical when building against 2.6, [...]
>
> I'm a bit confused here: There is still the CONFIG_SMP configuration
> option. I thought this should be set for MP kernels?

When OpenAFS is built against a 2.4 kernel, multiple modules get built in=20
different directories (MODLOAD-SP-* and MODLOAD-MP-*), with different=20
compiler options; among other things, we define certain macros in the MP=20
case which correspond to the options we think the kernel is built with.

It used to be the case that you could build against one non-SMP kernel and=20
get modules that would work for both that kernel and the corresponding SMP=20
kernel.  I don't think that's been true for a long time.

When building agsinst 2.6, you still get two directories, but they are (in=20
theory) identical -- we use the kernel's build process to build each=20
directory, and don't pass any compiler options of our own at all.

>  > However, the backtrace indicates that you're losing because of a null
>  > pointer dereference in src/afs/LINUX/osi_cred.c:crref().
>
> And it looks like it happens during module initialization. Why should
> there be a difference between SP and MP? (I don't have an MP system to
> play around, so I'm mostly guessing.)

I haven't a clue.