Differneces between US-III and US-IIIcu

[BERTRAND Joël <joel.bertrand%systella.fr@localhost>]

        Hello,

	I'm using NetBSD-current on two Blade-2000. Both run the same NetBSD 
system (currently 7.99.1 built from sources).

        First one contains two US-III/750 MHz and often panics with :

Sep  5 01:40:32 hilbert /netbsd: trap type 0x68: cpu 1, pc=41569284 
npc=41569288 pstate=0x44820082<,IE>
Sep  5 01:40:32 hilbert /netbsd: Skipping crash dump on recursive panic
Sep  5 01:40:32 hilbert /netbsd: panic: +fast data access MMU miss
Sep  5 01:40:32 hilbert /netbsd: cpu1: Begin traceback...
Sep  5 01:40:32 hilbert /netbsd: cpu1: End traceback...
Sep  5 01:40:32 hilbert /netbsd: cpu0: shutting down
Sep  5 01:40:32 hilbert /netbsd: cpu1: rebooting

under low load average (2 for the last panic). Second one contains two 
US-IIICu/900 MHz. If I swap CPU and replace US-III/750 MHz by 
US-IIICu/900 MHz, the same hardware seems to be rock solid. I can build 
system and pkgsrc in parallel without any trouble, even with a load 
average greater than 10 during several days.

	I don't know if this difference can help to debug kernel, but I suppose 
there are some differences between Cu CPU and non-Cu CPU that is not 
correctly handled by kernel.

        Regards,

        JKB