Re: Trying to convert old modules to newer kernels

[Sam Ravnborg <sam@ravnborg.org>]

On Thu, Dec 20, 2007 at 04:27:37PM -0500, linux-os (Dick Johnson) wrote:
> 
> On Thu, 20 Dec 2007, Sam Ravnborg wrote:
> 
> >>
> >> It never gets to the printk(). You were right about the
> >> compilation. Somebody changed the kernel to compile with
> >> parameter passing in REGISTERS! This means that EVERYTHING
> >> needs to be compiled the same way, 'C' calling conventions
> >> were not good enough!
> >
> > How did you build the module. It reads like you failed to use
> > kbuild to build your module which is why you did not pass
> > correct options to gcc - correct?
> >
> > If you did not use kbuild - why not?
> > Is there anything missing you need?
> >
> > 	Sam
> >
> 
> I need to get rid of -mregparm=3 on gcc's command line. It
> is completely incompatible with the standard calling conventions
> used in all our assembly-language files in our drivers. We make
> very high-speed number-crunching drivers that munge high-speed
> data into images. We need to do that in assembly as we have
> always done.
That I understand. So you need a CONFIG_ option to switch off
-regparm=3 and pray that the kernel assembly supports it.

And then I assume you avoided kbuild because it added -regparm=3
which is why your simple module broke.

As you are well aware there is not any testing of a kernel without
-regparm=3 these days so you should strongly consider making your
assembly module comply with -regparm=3.

And no - I dunno how much work that is and what impact it has
on your number chrunching stuff.
But it looks like the only sane long-term solution to me.

	Sam