[OpenBIOS] SOLVED: the mystery of Solaris on SPARC32 and the missing Forth arguments

[Mark Cave-Ayland]

Artyom Tarasenko wrote:

>> Does this sound reasonable? I'm surprised that one else has realised that
>> the obp_fortheval_v2 function signature was wrong, but I guess it probably
>> hardly gets used for anything these days.
> 
> Ops. Forgot to submit this patch back then. :(. Sorry.
> The reason was not getting too far with the patch, because of the
> broken memory management.

Okay; I've committed something which should do the trick to SVN as r915.

Hmmmm these symptoms look exactly like something on SPARC64 where 
various bits of memory were getting clobbered because of a lack of stack 
space... (goes and has a look)...

Right - it's definitely something related to the stack when calling from 
the client into OpenBIOS (or vice-versa). If you take a look at 
arch/sparc32/context.c and start increasing IMAGE_STACK_SIZE, say to 16K 
or 32K you'll see that things suddenly start to work much better.

I think its related to the flushing of register windows onto the stack 
when switching between the two. My thoughts are that this is probably 
related to Igor's SPARC64 patches here:

http://www.openfirmware.info/pipermail/openbios/2009-July/003762.html

I suspect that you'll need to come up with something along similar lines 
for SPARC32. Blue, any thoughts?


ATB,

Mark.

-- 
Mark Cave-Ayland - Senior Technical Architect
PostgreSQL - PostGIS
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