NetBSD Problem Report #35363
From email@example.com Fri Jan 5 21:52:06 2007
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Date: Fri, 5 Jan 2007 15:52:05 -0600 (CST)
Subject: 3.1_STABLE problems on dual nocache 50 MHz SuperSPARC (390Z50)
>Synopsis: MP broken for some 50 MHz SuperSPARC (390Z50) processors on 3.1
>Arrival-Date: Fri Jan 05 21:55:00 +0000 2007
>Originator: Johan A. van Zanten
>Release: NetBSD 3.1_STABLE
System: NetBSD vishnu 3.1_STABLE NetBSD 3.1_STABLE (MANGOLASSI.MP) #0: Sun Nov 5 17:37:17 CST 2006 johan@pangu:/tew/003/src/NetBSD/NetBSD-3/src/sys/arch/sparc/compile/MANGOLASSI.MP sparc
When the second processor is activated multi-processor 3.1_STABLE sun4m
systems, NetBSD behaves erratically, with some programs seg faulting. The
system is extremely unstable and not usable, but it does not panic.
Please see my email to port-sparc:
Confirmation of the problem by Michael-John Turner:
Please note that not all 50 MHz SuperSPARC processors trigger the problem.
I have the same OS building running without problems on a dual "390Z55"
system. My understanding is that a significant difference between CPUs
identified as "390Z50" and "390Z55" is that the '55 has 1 MB of ecache per
CPU, and the '50 has none.
Also, please note that i had a dual 390Z50 system running NetBSD
2.0.2_STABLE without problems, under significant load (Internet-connected
DNS server and MX, as well as KDC), before i upgraded to 3.1_STABLE.
Michael-John Turner's message above also suggests that the problem may
have been introduced between 2.x and 3.x.
Install a NetBSD 3.1 MP kernel (GENERIC.MP produces the problem) on a
sparc with two 390Z50 50 MHz processors.
Boot the system multi-user.
Removing the second CPU eliminates the problem, as does switching to
multiple CPUs of a different type, such as "390Z55" or other, faster SPARC
CPUs, all of which appear to have cache (and a cache controller).
$NetBSD: query-full-pr,v 1.36 2007/11/24 03:27:39 kano Exp $
$NetBSD: gnats_config.sh,v 1.8 2006/05/07 09:23:38 tsutsui Exp $
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