Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!elroy.jpl.nasa.gov!decwrl!sgi!shinobu!odin!anchor!olson
From: olson@anchor.esd.sgi.com (Dave Olson)
Newsgroups: comp.sys.sgi
Subject: Re: Problem with 4D-25S ?
Message-ID: <1991Mar27.023922.23035@odin.corp.sgi.com>
Date: 27 Mar 91 02:39:22 GMT
References: <9103261558.AA19295@euler.jsc.nasa.gov>
Sender: news@odin.corp.sgi.com (Net News)
Organization: Silicon Graphics, Inc.  Mountain View, CA
Lines: 33

In <9103261558.AA19295@euler.jsc.nasa.gov> johnson@EULER.JSC.NASA.GOV (Stan Johnson) writes:

| We have an IRIS 4D-25S set up as a fileserver (running 3.3.1).  We have an
| intermittent problem reading tar files from cartridge tapes: the message
| "WARNING: dma_map: address C055FFFF not word aligned" will display over
| and over until the machine is reset.  This is not at all repeatable, and
| our field service person was not able to find any problems after running
| all the diagnostics.

This happens when you have cabling problems sometimes, so that a device
sees a count incorrectly.  It can also happen if you have an unsupported
SCSI device that disconnects at any point in the transfer, rather than on
a word (4 byte boundary).  Due to a bug in the error handling code, it is
never recovered from.  It DOES recover from it in 4.0.

In any case, it is extremely unlikely to be a memory problem.  Check out
your scsi devices, cables, and termination.

| Another, possibly unrelated, error that I
| haven't been able to track down is the message "NOTICE: plp/audio:
| unexpected interrupt",

Sounds like you are using a parallel printer.  If the driver isn't expecting
an interrupt, you get this message.  It includes audio, because the same
chip and interrupt are used for both audio and the parallel port.
We do see this rarely on some of our print servers, and it usually is just
a less than optimal cable.  Nothing to worry about, unless it happens really
frequently.
--

	Dave Olson

Life would be so much easier if we could just look at the source code.