Re: [PATCH v2 2/2] m68k: Fix interrupt stack frames for 68000

[Geert Uytterhoeven]

Hi Daniel,

On Tue, Jan 9, 2024 at 3:10 PM Daniel Palmer <daniel@xxxxxxxx> wrote:
> On Mon, 8 Jan 2024 at 18:56, Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
> > I think it would be better to use the classic m68k stack frame.
> > That would pave the way for building a single nommu kernel for
> > MC680[012346]0 that runs on e.g. any Amiga.
> > MC68000 and Coldfire are incompatible anyway.
>
> While looking at how to do this I realised that the addql #2,%sp in
> RESTORE_ALL in entry.h will now break the stack frames for those fancy
> 68010+ users.
> So that needs to be #ifdef'd to make it only compile for 68000. I saw
> an error email from the next build stuff so I guess the change has
> been queued somewhere? If so I should send a fix..

AFAIK it hasn't been applied yet.  These days the bots also test
patches from mailing lists...

> I'm not sure how to actually make that generic without patching the
> code at runtime (remove the 68000 specific bit, reserve enough extra
> space to rewrite the code..) but it's a macro so not so simple.

Or use different entry points depending on CPU type?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68korg

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds