Re: reliable reproducer, was Re: core dump analysis

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Finn,

On Wed, Apr 19, 2023 at 12:53 PM Finn Thain <fthain@linux-m68k.org> wrote:
> Inspired by your observation about the page fault and stack growth, I
> wrote a small test program (given below) that just pushes registers onto
> the stack recursively while forking processes and collecting the SIGCHLD
> signals.
>
> On a Motorola '030 the stack grows to about 7 MiB before it gets
> corrupted. The program detects the stack corruption and terminates
> immediately with an illegal instruction. Oddly, the program never detects
> any stack corruption when run on the QEMU '040.

Nice! (the reproducer, not the bug ;-)

Does it also fail on a very old kernel image you still have lying around?
Just to rule out a recent kernel bug.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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