NetBSD 10.0 on sparc32 and HyperSparc hacking

Hi!

A couple of months passed, it is fall and rainy days are back, as well 
as cooler temperature for our old SparcStations.

Anybody can help getting NetBSD 10.0 stable on my SS4 and especially my 
SS20?

The SS20 has 2x HyperSPARC modules and it will just crash quite quickly. 
A bit of using kills it and drops into the console. In single-CPU mode 
it works.
NetBSD 9.2 was almost usable on it (it would die with strange issues 
after a couple of days, but connection was available and one could issue 
a reboot).

The SS4 (MicroSPARC) dies when compiling certain stuff. Hard. No message 
on console, just frozen (of course, it could have developed issues, but 
it was stable with 9.2!). It has also much less memory.

I'd really like get the SS20 usable again, also because it is the most 
powerful 32bit system I have, I can copy binaries over to the SS4 in case.

Michael? Romain? you crazy hackers?

Riccardo

PS: I would have one last resort I could do: I have a SS10 with 2x 
SuperSPARC II running 9.4 quite well. I could swap all 4 CPUs and see if 
9.4 runs stable and 10.0 not. Given that SS10 and SS20 are not exactly 
the same and the former has a slower bus, so some issue could not 
appear. I don't know if my ROMs take that swap though? I remember 
getting extra ROMs for HyperSPARC  almost 20 years ago, but my memory 
there is dead like the original nvram :)