[comp.unix.microport] SysV/386: db module not cofigured ???

carvalho@ernie.Berkeley.EDU (Marcio de Carvalho) (09/12/88)

	Maybe someone out ther might have encountered such error 
and can help me.
	At some apparently random accasions, my Everex 386/20
running uport's V/386 version 2.2 enters in a loop and fills
screens and more screens with:

*** Attention: attempting to run DEBUGGER with no db module configured

*** Attention: attempting to run DEBUGGER with no db module configured

*** Attention: attempting to run DEBUGGER with no db module configured

*** Attention: attempting to run DEBUGGER with no db module configured

	And the only way I found to get out of this is to turn 
the machine OFF and reboot it.
	Thanks for the help.

--Marcio
	
=--=--=--=--=--=--=--=--=--=--=--=--=--=--=--=--=--=--=--=--=--=--=--=--=--=
=                          Marcio de Carvalho                              =
=                                                         IEOR Department  =
= ...!ucbvax!ernie!carvalho          University of California at Berkeley  =

blair@obdient.UUCP (Doug Blair) (09/17/88)

In article <26061@ucbvax.BERKELEY.EDU>, carvalho@ernie.Berkeley.EDU (Marcio de Carvalho) writes:
> 
> 	At some apparently random accasions, my Everex 386/20
> running uport's V/386 version 2.2 enters in a loop and fills
> screens and more screens with:
> 
> *** Attention: attempting to run DEBUGGER with no db module configured
> 
> 	And the only way I found to get out of this is to turn 
> the machine OFF and reboot it.

We have also experienced a similar problem, in fact the ONLY problem
that we've had with microport SysV/386.  Our machine has on a couple
of occasions generated the same message when we have attempted to
cu -l ttyXX at the same time that another process is using another
one of the tty's for routine communications.  This happened in the
course of installing a new internal modem card; the card was being
removed and reconfigured (different interrupts and addresses, etc)
and reinstalled a few times.

I suspect we may have a bug related to the AT buss's inability to
have two boards with the same IRQ even throught the devices
don't have the same port address.

Comments, uport?

Thanks
Doug
 ___  _           _  _             _    
|   || |_  ___  _| ||_| ___  __  _| |_  Doug Blair    Obedient Software Corp.
| | ||  .\/ ._\/.  || |/ ._\|  \|_   _| 1007 Naperville Road1 +1 312-653-5527
|___||___/\___/\___||_|\___/|_|_| |_|   Wheaton, Illinois 60187 obdient!blair

scotty@l5comp.UUCP (Scott Turner) (09/21/88)

In article <835@obdient.UUCP> blair@obdient.UUCP (Doug Blair) writes:
>In article <26061@ucbvax.BERKELEY.EDU>, carvalho@ernie.Berkeley.EDU (Marcio de Carvalho) writes:
>> 
>> 	At some apparently random accasions, my Everex 386/20
>> running uport's V/386 version 2.2 enters in a loop and fills
>> screens and more screens with:
>> 
>> *** Attention: attempting to run DEBUGGER with no db module configured
>> 
>> 	And the only way I found to get out of this is to turn 
>> the machine OFF and reboot it.
>
>I suspect we may have a bug related to the AT buss's inability to
>have two boards with the same IRQ even throught the devices
>don't have the same port address.

This isn't a bug, they just don't ship the product with a kernel debugger
installed.

Of course what I don't understand is why the damn thing attempts to enter
the debugger when it KNOWS it ain't got one. :)

I think they should supply a dummy kernel debugger that comes up and says:
"Sorry to bother you, but I'm feeling a little unwell right now. So I'm
going to take a nice long nap."

Lord knows the damn fsck is probably going to munch yer hard drive when you
reboot so you better take a nap as well so you can deal with the stress.
"Oh God, tell me it isn't removing /bin/sh again!"

Why does the system double panic? Right now my system double panics whenever
I try to write to the floppy drive. (I'm SERIOUS folks) Something about a
user mode interrupt 0x2... Weird. I'm hoping that installing the system one
more time will clear that up.

The AT buss can deal with two boards using the same IRQ. The problem is that
the IRQ service routine must check BOTH devices before re-arming the 8259...
This gets REALLY hairy if you can't guarantee that you can re-arm the 8259
before one of the damn ports drops it's IRQ line again. I hope someone out
there knows why the 8259 is run edge triggered rather than level triggered,
I sure can't explain it...

Scott Turner
scotty@l5comp -or- uunet!l5comp!scotty

betel@swivax.UUCP (Michiel Betel) (09/30/88)

After numerous reinstallations of sysV/386 U2.2 we got rid of an
unexpected intterupt 0x4. This one occured at startup, gave a double Panic, 
entered the none existant db module and hung the system after dumping
2516 pages of core. It seems it was caused by a buggy devicedriver for
our multiport serial board, because since I've installed the new driver
the problem is gone.

This error message should really be documented, because the dump of registers
generates beautiful patterns but is not very usefull.

Michiel.

dave@pmafire.UUCP (Dave Remien) (10/03/88)

>From: betel@swivax.UUCP (Michiel Betel)
>Message-ID: <687@swivax.UUCP>

>After numerous reinstallations of sysV/386 U2.2 we got rid of an
>unexpected intterupt 0x4. This one occured at startup, gave a double Panic, 
>entered the none existant db module and hung the system after dumping
>2516 pages of core. It seems it was caused by a buggy devicedriver for
>our multiport serial board, because since I've installed the new driver
>the problem is gone.
>This error message should really be documented, because the dump of registers
>generates beautiful patterns but is not very usefull.

Various articles posted to this newsgroup (I think by John Sully of
Microport), and discussed on the Microport BBS, show how to use the
panic dump to figure out where in the kernel the panic occurred. I once
had a beta kernel Microport sent which had the debug module; you could
wander around (albeit blindly, without documentation) in the kernel and
look at things. I agree that an explanation of how to determine where
the panic was caused should be in the Sys Admin documentation.



-- 
----------
Dave Remien - WINCO Computer Engineering Group (only somewhat confused, now)
208-526-3523, 0800 to 1615 MDT; 208-524-1906, 1800 'til whenever
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