Re: A tale of bootstrap ld.so debugging

[Ludovic Courtès]

Hi Roland,

Roland McGrath <roland@hack.frob.com> skribis:

> I think what we used to say was that you should try to do debugging with
> sub-hurds where the console port is faked with io ports (I think).

The thing is that I was debugging a system cross-built from scratch, so
sub-hurds were not an option.

> We definitely don't want to clutter up ld.so with stuff that is only
> for debugging early boot.  I think it would be better to have
> serverboot supply a trivial io server on the fd ports it hands to the
> initial processes, that translates to console device_write calls in a
> very simple way.

Here the ‘ld.so /hurd/exec’ command line comes from GRUB and is spawned
by Mach directly (serverboot has been deprecated for years and is no
longer in the repository.)

Adding a term server or similar in the early boot process seems tricky
and would probably require tweaking the boot process in diskfs, exec,
& co. in ugly ways, AIUI.

Thanks,
Ludo’.