NetBSD Problem Report #11066

Received: (qmail 5174 invoked from network); 22 Sep 2000 06:29:17 -0000
Message-Id: <>
Date: Fri, 22 Sep 2000 17:29:11 +1100 (EST)
From: Simon Burge <>
Reply-To: Simon Burge <>
Subject: machine check with IDE DMA restoring from ISA SCSI tape
X-Send-Pr-Version: 3.95

>Number:         11066
>Category:       port-alpha
>Synopsis:       machine check with IDE DMA restoring from ISA SCSI tape
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    thorpej
>State:          closed
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Sep 22 06:30:00 +0000 2000
>Closed-Date:    Tue Oct 13 15:36:58 +0000 2020
>Last-Modified:  Tue Oct 13 15:36:58 +0000 2020
>Originator:     Simon Burge
>Release:        1.5_ALPHA2
Wasabi Systems
System: NetBSD 1.5_ALPHA2 NetBSD 1.5_ALPHA2 (THOREAU)
#12: Wed Sep 20 16:50:13 EST 2000 alpha

	I have an alpha PC164 with an IBM 46GB IDE disk, and an Exabyte
	8500 connected to a (ISA) Adaptec 1542B.  With ISA DMA enabled,
	restoring approx 1.2GB of data from tape results in a machine
	check, similar to:

		mces    = 0x1
		vector  = 0x660
		param   = 0xfffffc0000006060
		pc      = 0xfffffc0000300640
		ra      = 0xfffffc000036600c
		curproc = 0x0

	    panic: machine check

	The machine check has happened from 4 out of 4 attempts to
	restore data, each within about 500kB of 1.2GB of data.

	The PC and RA in the machine checks seem to be random.  For one,
	both the PC and RA were in pciide_dma_start, for another the
	PC was in idle and the RA in mi_switch, and another the PC in
	_pool_get and RA in wdc_get_xfer.  I don't have the PC and RA
	for the first machine check.

	Disabling DMA on the IDE disks (using flags 0x0ff0) stops
	the machine checks, as has switching to an NCR 53c810a SCSI
	controller for the Exabyte and leaving DMA enabled.

	Restore approx 1.2GB of data from tape - works every time.
	None given.
Responsible-Changed-From-To: port-alpha-maintainer->thorpej
Responsible-Changed-When: Tue, 13 Oct 2020 15:36:58 +0000

State-Changed-From-To: open->closed
State-Changed-When: Tue, 13 Oct 2020 15:36:58 +0000
Ancient PR, don't think we'll be getting to the bottom of this one.


NetBSD Home
NetBSD PR Database Search

(Contact us) $NetBSD: gnats-precook-prs,v 1.4 2018/12/21 14:20:20 maya Exp $
$NetBSD:,v 1.9 2014/08/02 14:16:04 spz Exp $
Copyright © 1994-2017 The NetBSD Foundation, Inc. ALL RIGHTS RESERVED.