Kernel panics and double panics

[Dave Hammond]

OS: Xenix 386, release 2.3.2, update R ("GT" upgrade kit)
Hardware: Everex 25mhz 386, 6 MB 32 bit RAM
Peripherals: 80387, ESDI drive, 60MB QIC tape, Arnet Smart-8 serial expander.

The system boots and operates normally for a period of time, but will
eventually panic with an error:

	Kernel Panic - Non-recoverable Kernel Page Fault.

The most recent panic (this morning) was followed by:

	Kernel Double Panic - Stack Fault.

The panics can occur hours or days apart, and (as yet) can not be
attributed to any specific condition.  The most obvious hint that the
problem is surfacing is when an exec?() call causes a segmentation
violation, without ever loading the program.  If the shell is attempting
the exec?(), this results in a "Memory fault, core dumped" message and a
return to the shell prompt.

System load does not appear to be an obvious factor.  Nor does command
argument length appear to be an issue, as a simple one word command
line, like "ps" or "vi", can fail.


The boot screen configuration info follows:

10 bits of I/O address decoding
Wed Dec 27 11:30:03

device    address	vector	dma	comment
----------------------------------------------------------------------------
%fpu      -		35	-	type=80387
%floppy   0x3F2-0x3F7	06	2	unit=0 type=96ds15
%serial   0x3F8-0x3FF	04	-	unit=0 type=Standard nports=1
%serial   0x2F8-0x2FF	03	-	unit=1 type=Standard nports=1
%parallel 0x378-0x37A	07	-	unit=0
%parallel 0x3BC-0x3BE	07	-	unit=1
%tape     0x300-0x304	05	1	type=W
Arnet Smartport with 8 ports on COM4
%console  -		-	-	unit=mono type=2
Wed Dec 27 11:30:04
%disk     0x1F0-0x1F7	36	-	type=W0 unit=0 cyls=1224 hds=7 secs=36
rootdev 1/40, pipedev 1/40, swapdev 1/41
mem: total = 10112k, reserved = 4k, kernel = 1764k, user = 8344k
kernel: drivers = 4k, 12 screens = 68k, 1024 i/o bufs = 1024k, msg bufs = 8k
nswap = 25000, swplo = 0, Hz = 50, maximum user process size = 15844k

Advice as to remedial action, debugging procedures, etc is desparately
sought!  E-mail is preferred, however, I read this newsgroup daily.

__
Dave Hammond 
EMAIL: daveh at marob.masa.com
VOICE: 516-872-3535
FAX: 516-872-3579