From owner-freebsd-stable  Mon Jun 17 08:07:39 1996
Return-Path: owner-stable
Received: (from root@localhost)
          by freefall.freebsd.org (8.7.5/8.7.3) id IAA23706
          for stable-outgoing; Mon, 17 Jun 1996 08:07:39 -0700 (PDT)
Received: from rich.isdn.bcm.tmc.edu (root@RICH.ISDN.BCM.TMC.EDU [128.249.250.34])
          by freefall.freebsd.org (8.7.5/8.7.3) with ESMTP id IAA23701
          for <freebsd-stable@freebsd.org>; Mon, 17 Jun 1996 08:07:36 -0700 (PDT)
Received: from richc.isdn.bcm.tmc.edu (root@richc.isdn.bcm.tmc.edu [128.249.250.37]) by rich.isdn.bcm.tmc.edu (8.7.5/8.6.12) with ESMTP id KAA06624; Mon, 17 Jun 1996 10:07:34 -0500 (CDT)
Received: (rich@localhost) by richc.isdn.bcm.tmc.edu (8.7.5/8.6.12) id KAA00642; Mon, 17 Jun 1996 10:07:33 -0500 (CDT)
Date: Mon, 17 Jun 1996 10:07:33 -0500 (CDT)
Message-Id: <199606171507.KAA00642@richc.isdn.bcm.tmc.edu>
From: Rich Murphey <rich@rich.isdn.bcm.tmc.edu>
To: jdw@wwwi.com
CC: freebsd-stable@freebsd.org
In-reply-to: <199606170804.BAA14727@voltimand.csd.wwwi.com> (jdw@wwwi.com)
Subject: Re: Trap 12/supervisor read, page not present
Reply-to: rich@rich.isdn.bcm.tmc.edu
Sender: owner-stable@freebsd.org
X-Loop: FreeBSD.org
Precedence: bulk

|Here is the machine:
|ASUS P54NP EISA/PCI Dual-proc motherboard (1 90Mhz Pentium Processor)
|2x32mb 70ns SIMMs
|Adaptec AHA-2940W Controller
|  Quantum Empire 2100S (2gig)
|  Quantum Atlas 34300W (4gig, wide)
|Brand X I/O IDE
|  Micropolis 1.5gig drive jumpered to act as a 500meg and a 1gig
|  because of controller age
|3Com 3c509 (ISA, running 10BaseT)
|Brand X Cirrus ISA video card
|
|I'll replace any part except the SCSI disks and the RAM to make it work.
|This machine previously ran Unixware 2.0 (sold to SCO, ugh), and Linux
|(just didn't like Linux) under similar workloads without problems but 
|that by now means rules out some new failure.  The Atlas is the only 
|new component because a Grand Prix died under the pressure of being news
|spool.

Perhaps this is a long shot, but I've seen a problem
with tagged commands on an Atlas connected to an NCR
controller here.  When I disabled the tags via:

ncrcontrol -u 0 -t 0 -s tags=0

It eliminated kernel panics that would occur beginning
with the messages:

sd0(ncr0:0:0): COMMAND FAILED (4 28) @f0ab1800

This indicates that the queue is full on the Atlas.  I
don't know why this happens but once I disabled tags
the problems went away.  It's not obvious to me now how
do that with the ahc driver, but it might be worth
trying.  Rich