port-alpha/47285: fatal kernel trap when booting NetBSD CD on DEC 3000

[oreissig%gmail.com@localhost]

>Number:         47285
>Category:       port-alpha
>Synopsis:       fatal kernel trap when booting NetBSD CD on DEC 3000
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    port-alpha-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Dec 04 23:35:00 +0000 2012
>Originator:     Oli
>Release:        6.0
>Organization:
>Environment:
not available yet
>Description:
When booting from the official NetBSD 6.0 ISO for Alpha on my DEC 3000 the 
kernel panics during boot. Here is a complete boot log:

DEC 3000 - M400
Digital Equipment Corporation
System conducting power up tests
------------------------------------------------------------

Devnam           Devstat
--------         -------
     CPU          OK KN15-BA -V7.0-S887-I21F-sV1.0-DECchip 21064  P3.0
     OSC          133 MHz
    ASIC          OK
     MEM          OK 128MB
     NVR          OK
     SCC          OK ptr(0) = Not Present  keybd(2) = Not Present
      NI          OK Ethernet Address: 08-00-2B-3D-DD-E5 , TENBT
    SCSI          OK
    ISDN          OK
     TC0          STS-NOT-TESTED - PMAGB-BA
------------------------------------------------------------
System power up OK.
Enter B to boot software from DKA0

>>> boot dkb600
INIT-S-CPU...
AUDIT_BOOT_STARTS ...
AUDIT_CHECKSUM_GOOD
AUDIT_LOAD_BEGINS
AUDIT_LOAD_DONE

NetBSD/alpha 6.0 ISO 9660 Primary Bootstrap
Jumping to entry point...

NetBSD/alpha 6.0 Secondary Bootstrap, Revision 1.13

VMS PAL rev: 0x100010538
OSF PAL rev: 0x2012d
Switch to OSF PAL code succeeded.

Boot flags: A
10201632+202344=0x9ec770

Entering netbsd at 0xfffffc0000431230...
Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
    2006, 2007, 2008, 2009, 2010, 2011, 2012
    The NetBSD Foundation, Inc.  All rights reserved.
Copyright (c) 1982, 1986, 1989, 1991, 1993
    The Regents of the University of California.  All rights reserved.

NetBSD 6.0 (INSTALL)
DEC 3000 - M400, 133MHz, s/n
8192 byte page size, 1 processor.
total memory = 128 MB
(2048 KB reserved for PROM, 126 MB used by NetBSD)
avail memory = 114 MB
mainbus0 (root)
cpu0 at mainbus0: ID 0 (primary), 21064-1
tcasic0 at mainbus0
tc0 at tcasic0: 25 MHz clock
ioasic0 at tc0 slot 7 offset 0x0: fast mode
le0 at ioasic0 offset 0xc0000: address 08:00:2b:3d:dd:e5
le0: 32 receive buffers, 8 transmit buffers
zsc0 at ioasic0 offset 0x100000
vsms0 at zsc0 channel 0
wsmouse0 at vsms0 (mux ignored)
zstty0 at zsc0 channel 1
zsc1 at ioasic0 offset 0x180000
lkkbd0 at zsc1 channel 0
wskbd0 at lkkbd0 (mux ignored)
zstty2 at zsc1 channel 1 (console i/o)
mcclock0 at ioasic0 offset 0x200000: mc146818 compatible time-of-day clock
AMD79c30 at ioasic0 offset 0x240000 not configured
tcds0 at tc0 slot 6 offset 0x0: TurboChannel Dual SCSI (baseboard)
asc0 at tcds0 chip 0: NCR53C94, 25MHz, SCSI ID 7
scsibus0 at asc0: 8 targets, 8 luns per target
asc1 at tcds0 chip 1: NCR53C94, 25MHz, SCSI ID 7
scsibus1 at asc1: 8 targets, 8 luns per target
sfb0 at tc0 slot 3 offset 0x0
CPU 0: fatal kernel trap:

CPU 0    trap entry = 0x3 (instruction fault)
CPU 0    a0         = 0x2
CPU 0    a1         = 0x0
CPU 0    a2         = 0x0
CPU 0    pc         = 0xfffffc0000783f38
CPU 0    ra         = 0xfffffc000065185c
CPU 0    pv         = 0x0
CPU 0    curlwp     = 0xfffffc000094b480
CPU 0        pid = 0, comm = system

panic: trap
Stopped in pid 0.1 (system) at  fffffc0000496da8:       ret     zero,(ra)
db>

>How-To-Repeat:
boot from CD, always happens
>Fix: