Subject: System hangs, and a kernel trace

From: Andrew Cherry <[email-masked]>

A while back, I reported having problems with the current
kernel and system hangs, seemingly related to disk activity.
Recently, I've switched to using screen instead of X, so
that if any of these hangs turn out to be panics, I would
see them.  As luck would have it, my system froze up again
recently, but the kernel was apparently still watching for
keystrokes, since I was able to break into the debugger.
Here is the result of a trace; I hope this will be of some
use to tracking down the bug.  No doubt some of the info
won't be important, but here's the entire trace anyway:

db> trace
_Debugger(59,88,0,303ffe,2000) + 6
_ite_filter(59,0,8,88,0) + 158
_kbdintr(8) + 52
_dispatch_cia_ints(0,88,fffffd00,b04ee,d01) + 32
_ciaa_intr(d01,8,fffffd40,762,2200) + 16
_intrhand(2200) + e2
_lev4intr(?)
_trap(8,d01,303ffe) + 1a
_addrerr(?)
_uiomove(8764f4,947,ffffff24,947,0) + e0
_ffs_write(fffffecc) + 358
_vn_write(5c07c0,ffffff24,5bab80) + ae
_write(5b7000,ffffff84,ffffff7c) + a4
_syscall(4) + 138
_trap0() + e

My system is:

A2000, ECS
GVP G-Force 68040 with 12MB 32-bit RAM
GVP I/O Extender (G-Force also has I/O Extender hardware built in)
Seagate ST31200N SCSI-2 drive, sync enabled
Archive Viper 2525S tape drive

I also reported a panic that occurred when accessing adosfs
partitions; for the record, I wasn't doing any adosfs stuff
when this hang occurred, nor was I using the tape drive.

o These hangs have been occuring for me since mid-July.
o They occur both with and without the I/O Extender plugged
	in (I had the I/O Extender out for about a month,
	and still had the system freeze up often).
o They occur with or without the tape drive (the system hangs
  were in fact the primary motivation for buying a tape drive :) )
o The hangs happen with sync enabled or disabled.  (They also
  occur both with kernels I've compiled myself and with kernels
  obtained from the binary distribution.  I am using the GENERIC
  configuration for compilation).

I can provide more information or try various things out if
anyone has any ideas.  I hope the above info is helpful;
I've seen several other reports of disk-related system
freezes.

-Andrew Cherry
([email-masked])