SCSI changes for Indy machines?

Hi,

It's been a while since I've had my SGI Indy running NetBSD, and I figured 
I'd get it running NetBSD 4. I loaded a freshly cross-compiled netbsd-4 
GENERIC kernel and OS via NetBSD-3 which was already on this machine, but 
it can't go multiuser with NetBSD-4 (I have two drives - one with NetBSD-3 
and one with NetBSD-4):

scsibus0: waiting 2 seconds for devices to settle...
sd0 at scsibus0 target 1 lun 0: <SEAGATE, ST34371W, 0280> disk fixed
sd0: 4148 MB, 5168 cyl, 10 head, 164 sec, 512 bytes/sect x 8496960 sectors
sd0: sync (200.00ns offset 12), 8-bit (5.000MB/s) transfers, tagged 
queueing
sd1 at scsibus0 target 2 lun 0: <Maxtor 6, B250R0, BAH4> disk fixed
sd1: 233 GB, 121586 cyl, 64 head, 63 sec, 512 bytes/sect x 490234752 
sectors
sd1: sync (200.00ns offset 8), 8-bit (5.000MB/s) transfers, tagged 
queueing
probe(wdsc0:0:3:0): wdsc0: timed out; asr=0x20 [acb 0x97dc4f88 (flags 0x1, 
dleft
  24)], <state 5, nexus 0x97dc4f88, resid 24, msg(q 0,o 
0)>probe(wdsc0:0:3:0): AB
ORT in timeout: csr=0xff, asr=0x20
probe(wdsc0:0:3:0): sending ABORT command
probe(wdsc0:0:3:0): Resetting bus
probe(wdsc0:0:3:0): wdsc0: timed out; asr=0x00 [acb 0x97dc4f88 (flags 
0x41, dlef
t 24)], <state 8, nexus 0x97dc4f88, resid 24, msg(q 0,o 
0)>probe(wdsc0:0:3:0): A
BORT in timeout: csr=0x01, asr=0x00
probe(wdsc0:0:3:0): sending ABORT command
probe(wdsc0:0:3:0): sending DISCONNECT to target
wd33c93_wait: TIMEO @904 with asr=x0 csr=x1
wd33c93_wait: TIMEO @904 with asr=x0 csr=x1
wd33c93_wait: TIMEO @904 with asr=x0 csr=x1
wd33c93_wait: TIMEO @904 with asr=x0 csr=x1
wd33c93_wait: TIMEO @904 with asr=x0 csr=x1
wd33c93_wait: TIMEO @904 with asr=x0 csr=x1
wd33c93_wait: TIMEO @904 with asr=x0 csr=x1
wd33c93_wait: TIMEO @904 with asr=x0 csr=x1
wd33c93_wait: TIMEO @904 with asr=x0 csr=x1

After doing this for a while, the system reboots itself.

Any ideas about what might've changed that could've caused this? The 
system is fine and happy with any amount of I/O on either or both disks 
when booted into NetBSD-3.

The Indy, BTW , is new enough that it boots ELF directly with an R4600.

Thanks,
John Klos