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Conference turris::digital_unix

Title:DIGITAL UNIX(FORMERLY KNOWN AS DEC OSF/1)
Notice:Welcome to the Digital UNIX Conference
Moderator:SMURF::DENHAM
Created:Thu Mar 16 1995
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:10068
Total number of notes:35879

9056.0. "debug crahses the system: Urgent help" by GRIFUN::BENVI () Thu Mar 06 1997 15:07

Hi all,
	I'm involved in a very strange situation at a customer's site.
There is a AlphaStation 255 4/233 with Digital Unix 4.0B and latest firmware version.
The system has been installed with a custom installation specifying all the
subset and all the kernel options.
We wrote this simple and silly program: (I posted the line numbers as seen by the debugger)

1	#include <stdio.h>
2	main()
3	{	
4		printf("hello\n");
5	}
We tried to debug this with ladebug (V4.0-25 and 4.0-30), dbx and gdb
we issued:
stop at 4
run
in EVERY case the system crashed with an illegal instruction.

If we booted the system with the generic kernel (/genvmunix) the behavior is
correct.

We tried to builkd a new kernel with the following procedure:
boot /genvmunix
doconfig
select all the components

the newly created kernel has the same trouble as the one build by the installation procedure.

What can be the cause of the problem?
What can I look at?
I must solve this asap, customer now is working with the generic kernel, but he'll have
to build a new one....
By the way.Why the genvmunix is smaller than vmunix?

HELP!!!
Thanks in advance
	Angelo
T.RTitleUserPersonal
Name		DateLines
9056.1SMURF::DENHAMDigital UNIX KernelThu Mar 06 1997 15:2625
    There must a real patch on the way for this soon, but I don't
    have details.
    
    Two *easy* workarounds for this:
    
    1. Comment out options KDEBUG in /usr/sys/conf/SYSTEM-NAME:
    
       #options KDEBUG
    
    2. As root:
    
       Fix the running kernel:
    
       . # dbx -k /vmunix
       . (dbx) a db_enable = 0
       . (dbx) q
    
       Fix the on-disk kernel image, in case of reboots:
    
       . # dbx /vmunix
       . (dbx) patch db_enable = 0
       . (dbx) q
9056.2please send crash-data to CANASTA Mail ServerHAN::HALLEVolker Halle MCS @HAO DTN 863-5216Thu Mar 06 1997 18:0616
    re: .0
    
    Angelo,
    
    could you please obtain the crash-data file from the system and send it
    to the CANASTA Mail Server ? Please use the following command:
    
    # Mail -s "Diagnose case=dunix_9056 customer=notes_on_turris" 
    			can_server@xocomp.enet.dec.com < crash-data.n
    
    Once I see the footprint of that crash, I can write a rule for
    CANASTA. For information about CANASTA, please read note 8919.
    
    Thanks,
    
    Volker.
9056.3help on the way...QUARRY::petertrigidly defined areas of doubt and uncertaintyThu Mar 06 1997 18:0610
There is a patch on the way.  I tested it out recently and it appears to 
work fine.  It should be in the next patch release for V4.0b.  Yet another
workaround is:

 Add the following to the /etc/sysconfigtab as a workaround.

kdebug:
	kdebug_saveterm = 0

PeterT