Subject: re: sparc ELF kernels with a miniroot are broken.
To: matthew green <firstname.lastname@example.org>
From: Jonathan Stone <jonathan@DSG.Stanford.EDU>
Date: 06/23/1999 21:03:06
>> If you link a kernel with -m, does the link map look sane?
>uh, i have no idea what this means.
Invoke ld (by hand) so as to get a linker map. Check the output to
see ld is putting the .bss data for the miniroot in the right segment.
>> What about objdump output?
>anything in particular? i can output probably 1M of 'useful'
>data with objdump and this file. :-)
Check the ELF program header and the ELF section headers.
objdump --file-headers ./netbsd
objdump --section-headers ./netbsd
Check that the ELF program-section layout from the first looks okay,
and then that the section headers are laid out in a plausible order,
with appropriate alignment constraints, and with VMAs/LMAs that are
consistent with the file-header sections.
If those look OK try
which will dump both the above, plus the symbol table, too.
(hm, you might have to do objdump --full-headers | head -10
to get the program header: I forget).
Or you could do binary-search on the size allocated for a miniroot,
looking for a thresh-hold where things break; and then compare the
program and section headers, on the broken and non-broken kernels,
looking for inconsistencies.
>> If you build a miniroot kernel but dont stuffing a .fs into the
>> miniroot space, and try and boot it, does that at least get loaded (up
>> to trying to mount root)?
>as i meantioned earlier, it is broken before mdsetimage runs. the
>exact same lossage happens either way.
Oh. Sorry. I did look, but didnt find any mention of that; just
taking out MIN[I]ROOT altogether.