12/20 snapshot osiop(4) changes ?

...my "HP 9000/712/60 (Gecko) PA-RISC 1.1f" won't boot past the SCSI  
disk probe.  it works with the 3.4 release kernel/lif.  there's some HP  
debugging codes listed but i doubt they're very insightful.  how do i  
go about jumping into the kernel debugger and running a backtrace from  
here?

osiop0 at gsc0 offset 6000 irq 9: NCR53C710 rev 2, 40MHz, SCSI ID 7
scsibus0 at osiop0: 8 targets
osiop0: target 0 now using 8 bit 10 MHz 8 REQ/ACK offset xfers
sd0 at scsibus0 targ 0 lun 0: <SEAGATE, ST32430N SUN2.1G, 0444> SCSI2  
0/direced
sd0: 2049MB, 3992 cyl, 9 head, 116 sec, 512 bytes/sec, 4197405 sec  
total
0x02.CBF0
0x02.503F

...now, i notice on the 3.4 release kernel that the next step *would*  
be:

sti0 at mainbus0 offset 8000000 irq 11: HPA208LC640 rev 8.04;7, ID  
0x2B4DED6D40A00499
sti0: 2048x1024 frame buffer, 640x480x8 display, offset 0x0
sti0: 8x16 font type 1, 16 bpc, charset 0-255

...why perhaps could explain why i'm seeing a "hang", as I'm booted  
using a serial console per the FAQ instructions.  perhaps i'm not  
seeing a SCSI problem, but perhaps a sti(4) / video / serial console  
problem?

the last snapshot i installed couldn't have been more than 6 weeks old.

...thoughts?
-lava