My first real crash of NetBSD/alpha just happened now (apart from those
Miata dma hardware-induced ones, that is). I was playing with cdrecord,
and at some point after interrupting the n-th trial run, the machine
dropped into ddb. I only saw this when I turned on the console terminal,
so I didn't see immediately what happened. After reboot, the following
appeared in dmesg's output:

isp0: mbox cmd 15 failed with error 0
isp0: isp_control MBOX_ABORT failure (code 0)
isp0: isp_watch failed to abort command
isp0: Ultra Mode Capable
isp0: Board Revision 1040B, loaded F/W Revision 7.55
isp0: Last F/W revision was 5.57
isp0: transport error
panic: pmap_emulate_reference(0xfffffc0002247cb0, 0xfffffe00041fa000, 0, 1): pa
0x0 not managed
syncing disks... <4>ne0: warning - receiver ring buffer overrun
25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 giving up
sd0: WARNING: cache synchronization failed
rebooting...

Does this ring a bell, or should I file a pr? (Of course by now I could
have upgraded to 1.4.2, but I haven't done that yet).

Further dmesg output (from the reboot):

[ preserving 178160 bytes of netbsd ELF symbol table ]
Copyright (c) 1996, 1997, 1998, 1999
    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 1.4.1 (AZENOMEI) #24: Wed Apr 19 15:24:25 CEST 2000
    rhialto@azenomei.falu.nl:/usr/src/sys/arch/alpha/compile/AZENOMEI
Digital Personal WorkStation 433au, 432MHz
8192 byte page size, 1 processor.
real mem = 67108864 (2039808 reserved for PROM, 65069056 used by NetBSD)
avail mem = 54296576
using 794 buffers containing 6504448 bytes of memory
mainbus0 (root)
cpu0 at mainbus0: ID 0 (primary), 21164A-0 ()
cia0 at mainbus0: DECchip 2117x Core Logic Chipset (Pyxis), pass 1
cia0: extended capabilities: 1<BWEN>
cia0: using BWX for PCI config access
cia0: WARNING: Pyxis pass 1 DMA bug; no bets...
pci0 at cia0 bus 0
pci0: i/o enabled, memory enabled
de0 at pci0 dev 3 function 0
de0: interrupting at dec 550 irq 8
de0: DEC 21143 [10-100Mb/s] pass 3.0
de0: address 00:00:f8:75:ba:d3
de0: enabling 10baseT port
pciide0 at pci0 dev 4 function 0: CMD Technology PCI0646
pciide0: hardware does not support DMA
pciide0: primary channel wired to compatibility mode
atapibus0 at pciide0 channel 0
cd0 at atapibus0 drive 0: <TOSHIBA CD-ROM XM-6102B, 7800327909, 1106> type 5 cdrom removable
cd0: 32-bits data port
cd0: drive supports PIO mode 3, DMA mode 2
pciide0: secondary channel wired to compatibility mode
wd0 at pciide0 channel 1 drive 0: <IBM-DPTA-353750>
wd0: drive supports 16-sector pio transfers, lba addressing
wd0: 35772MB, 16383 cyl, 16 head, 63 sec, 512 bytes/sect x 73261440 sectors
wd0: 32-bits data port
wd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 4
cd0(pciide0:0:0): using PIO mode 3
wd0(pciide0:1:0): using PIO mode 4
sio0 at pci0 dev 7 function 0: Intel 82378ZB System I/O (SIO) (rev. 0x43)
vga0 at pci0 dev 11 function 0: S3 86C864-1 ("Vision864") (rev. 0x00)
wsdisplay0 at vga0
ppb0 at pci0 dev 20 function 0: Digital Equipment DECchip 21152 PCI-PCI Bridge (rev. 0x02)
pci1 at ppb0 bus 1
pci1: i/o enabled, memory enabled
isp0 at pci1 dev 8 function 0
isp0: interrupting at dec 550 irq 20
isp0: Ultra Mode Capable
isp0: Board Revision 1040B, loaded F/W Revision 7.55
isp0: Last F/W revision was 5.57
isp0: driver initiated bus reset
scsibus0 at isp0: 16 targets, 8 luns per target
sd0 at scsibus0 targ 0 lun 0: <DEC, RZ1CC-BA (C) DEC, 883F> SCSI2 0/direct fixed
sd0: 4091MB, 3708 cyl, 20 head, 113 sec, 512 bytes/sect x 8380080 sectors
cd1 at scsibus0 targ 4 lun 0: <YAMAHA, CRW4416S, 1.0h> SCSI2 5/cdrom removable
probe(isp0:4:1):  Check Condition on CDB: 0x00 20 00 00 00 00
    SENSE KEY:  No Additional Sense
     ASC/ASCQ:  No Additional Sense Information

probe(isp0:4:2):  Check Condition on CDB: 0x00 40 00 00 00 00
    SENSE KEY:  No Additional Sense
     ASC/ASCQ:  No Additional Sense Information

probe(isp0:4:3):  Check Condition on CDB: 0x00 60 00 00 00 00
    SENSE KEY:  No Additional Sense
     ASC/ASCQ:  No Additional Sense Information

probe(isp0:4:4):  Check Condition on CDB: 0x00 80 00 00 00 00
    SENSE KEY:  No Additional Sense
     ASC/ASCQ:  No Additional Sense Information

probe(isp0:4:5):  Check Condition on CDB: 0x00 a0 00 00 00 00
    SENSE KEY:  No Additional Sense
     ASC/ASCQ:  No Additional Sense Information

probe(isp0:4:6):  Check Condition on CDB: 0x00 c0 00 00 00 00
    SENSE KEY:  No Additional Sense
     ASC/ASCQ:  No Additional Sense Information

probe(isp0:4:7):  Check Condition on CDB: 0x00 e0 00 00 00 00
    SENSE KEY:  No Additional Sense
     ASC/ASCQ:  No Additional Sense Information

ne0 at pci1 dev 9 function 0: RealTek 8029 Ethernet
ne0: 10base2, 10baseT, 10baseT-FDX, auto, default auto
ne0: Ethernet address 52:54:05:f0:bd:1b
ne0: interrupting at dec 550 irq 24
isa0 at sio0
com0 at isa0 port 0x3f8-0x3ff irq 4: ns16550a, working fifo
com0: console
com1 at isa0 port 0x2f8-0x2ff irq 3: ns16550a, working fifo
lpt0 at isa0 port 0x3bc-0x3bf irq 7
sb0 at isa0 port 0x220-0x237 irq 5 drq 1: dsp v3.01
midi0 at sb0: <SB MIDI UART>
audio0 at sb0: half duplex
opl0 at sb0: model OPL3
midi1 at opl0: <SB Yamaha OPL3>
sb: can't map i/o space 0x220/24 in probe
pckbc0 at isa0 port 0x60-0x64
pcppi0 at isa0 port 0x61
spkr0 at pcppi0
isabeep0 at pcppi0
fdc0 at isa0 port 0x3f0-0x3f7 irq 6 drq 2
fd0 at fdc0 drive 0: 1.44MB, 80 cyl, 2 head, 18 sec
mcclock0 at isa0 port 0x70-0x71: mc146818 or compatible
root on sd0a dumps on sd0b
isp0: Target 0 at 20MHz Max Offset 8, 16 bit wide, Tagged Queueing Enabled
root file system type: ffs
IP Filter: initialized.  Default = pass all, Logging = disabled
de0: enabling 100baseTX port