My Sun-3/150 just exhibited the "short transfer: wanted 10 got 6."
misbehavior.  Here's what happened; I was doing a network comparison
that would have been doing a lot of reads, but no writes except
possibly for inode access time updates:

[Daily-Planet] 92> si0: SCSI bus busy, resetting...
ncr5380_command: short transfer: wanted 10 got 6.
si(0:0:0)-28,0,0,4,e6,40,0,0,4,0-
Stopped at      _Debugger+0x6:  unlk    a6
db> 

So I remembered what someone said, and typed "call ncr5380_show_state",
which produced

sc_ncmds=1
req 0: (sr=0xe54a0a4)TID=0 LUN=0 dh=0x0 dptr=0xe77a000 dlen=0x800 flags=3 stat=2
xs(0xe541900): flg(0x811)sc_link(0xe551fc0)retr(0x4)timo(0x2710)cmd(0xe54195a)len(0xa)data(0xe77a000)len(0x800)res(0x800)err(0x0)bp(0xe73be7c)sd0(si0:0:0): command: 28,0,0,4,e6,40,0,0,4,0-[2048 bytes]
------------------------------
000: 4d 5f be 4c b5 b9 b5 88 f2 80 23 c6 cb c0 7b 99 
016: f1 3f b6 03 8b 89 97 98 74 09 d3 81 d0 eb 65 dd 
032: 43 09 52 9d 13 5c b5 ed ca 3b a4 0b b8 13 22 f3 
048: a4 7d 02 ec aa e6 0a 23 12 5a 73 00 1a fa 62 f1 
------------------------------
sc_rr=0, current=0
Active request matrix:
TID=0 LUN=0 sr=0xe54a0a4
sc_state=0x1
sc_current=0xe54a0a4
sc_dataptr=0xe77a000
sc_datalen=0x800
sc_prevphase=6
sc_msgpriq=0x0
0xffffffff
db> 

I didn't try the show_trace call because I had no way to save the
voluminous result.  Instead, I typed "cont", which resulted in

panic: ncr5380_scsi_cmd: polled request, abort failed
Stopped at      _Debugger+0x6:  unlk    a6
db> 

So I just let it crash and reboot...

The disk is reported as

si0 at vmes0 addr 0xff200000 level 2 vector 0x40
scsibus0 at si0
si0 targ 0 lun 0: <SEAGATE, ST15230N, 0498> SCSI2 0/direct fixed
sd0 at scsibus0: 4095MB, 3992 cyl, 19 head, 110 sec, 512 bytes/sec

and I will be glad to provide any further info desired.  I may even be
able to make it happen again, if I'm (un)lucky.

					der Mouse

			    mouse@collatz.mcrcim.mcgill.edu