Locked VT

Locked VT

Post by Mike Tom Frantz » Tue, 06 Apr 1999 04:00:00



As I was writing a lab report, one of my VT windows locked.
I tried hitting scroll lock, control-O, control-q,j, and almost every
other one but no dice.  Switched keyboards, banged it against my head,
swore alot *alot*.
I do get a 'Keyboard LED command not ACKed' in dmesg.

When I try to change the vt with scon, it reports:
ioctl VGAGETSCREEN failed: Inappropriate ioctl for device

Any suggestions other than reboot?  Does the pcvt driver accept modem
control codes that could have locked it?

Now I am hugging my Sparc 20 and considering trading in the intel box as
a down payment on an Ultra-5.

The way it is looking, I'll be having a rebooting funeral on thursday
and get really really drunk.

later,
.mike

---

Every one we don't catch would be a "yet another major ms security hole",
and the theory tells us we can't catch all of them.  So, we're just not
going to start down that path.

 
 
 

Locked VT

Post by Julien Oste » Tue, 06 Apr 1999 04:00:00


I'm afraid I might not help you, but I think I guess _why_ it locked...

    Mike> As I was writing a lab report, one of my VT windows locked.  I tried
    Mike> hitting scroll lock, control-O, control-q,j, and almost every other
    Mike> one but no dice.  Switched keyboards, banged it against my head,
    Mike> swore alot *alot*.  I do get a 'Keyboard LED command not ACKed' in
    Mike> dmesg.

Hm. Do you have an odd/old keyboard? There is a problem in the pcvt driver,
which aims to be already fixed (which OpenBSD are you using?), it sounds
pretty much like that. You can read about it in the pcvt FAQ, I think it
resides in /usr/src/sys/arch/i386/isa/pcvt/Doc/FAQ. It is reported, that
especially old keyboards could hang the pcvt driver. The reason is that the
keyboard doesn't allow changing the keyboard LEDs from the computer, it has an
internal mechanism to switch the LEDs on or off at keypress. This, of course,
is very bad behaviour and happens only on very old keyboards.

After thinking about it... no, I don't think you have such an old keyboard, do
you? But what has happened is almost obvious. Maybe the hardware of your
keyboard is easy influencable by external interferences or it just failed at
the moment... your system tried to set the status of the keyboard LEDs
and... mayber your keyboard was* or not getting the request, nobody can
say, but it never responded to your computer. Now the keyboard controller
hangs.

    Mike> When I try to change the vt with scon, it reports: ioctl
    Mike> VGAGETSCREEN failed: Inappropriate ioctl for device

Hm :(

    Mike> Any suggestions other than reboot?  Does the pcvt driver accept
    Mike> modem control codes that could have locked it?

I don't think that this could happen... you're just an unlucky boy, as it
seems, beaten down by something that _can_ happen, but never actually _does_
happen.

    Mike> Now I am hugging my Sparc 20 and considering trading in the intel
    Mike> box as a down payment on an Ultra-5.

    Mike> The way it is looking, I'll be having a rebooting funeral on
    Mike> thursday and get really really drunk.

So you still have access via telnet? Well, tell me if it worked, don't expect
to much, don't get too drunk if it won't work :) but try the following:

kcon -R

and pray. Let me know if it could solve your problem.

Oh, yes, and if the problem persists, which might tell you that your mainboard
firmware, your keyboard controller or your keyboard is instable in this
aspect, read the pcvt FAQ. I think there is a (compiletime?) workaround, which
disables keyboard LED handling.

Good luck.

--
  /--/ Julien Oster /---/ www.fuzzys.org <---> www.sysadm.cc /---/
 /--/ OpenBSD  2.5 /---/ Greetings  from  Munich,   Germany /---/


 
 
 

1. ctrl-C locks VT terminal

Hello gurus...

I have small but painfull problem..
My environment :
Compaq Alpha ES40, tru64Unix 5.1
vt420 terminal device with TERM=vt220 in the KORN shell
In the output of stty -a ; Intr is ^C

The problem ;
when I put
set -o emacs in .profile
ctrl-C locks the SESSION.For example, if I write ls -l and tries to
cut the flow (I press ctrl-C) Interrupt key locks the SESSION.
I have found that this is due to set -o emacs in the .profile. When I
comment that line, everything works nicely...

Now I want to ask ;
1- I have installed bash..(2.03). Which is working good so far.. Can I
use it without any problem instead of ksh. I have some scripts, Do
they run without *any change* ?? What about Initialization files i.e.
profiles, do they need any change..? (I think bash reads profiles..)

2- How can I use line-editing property (set -o emacs) in ksh WITHOUT
THIS PROBLEM..

thanks in advance ..

selcuk karaca
Unix Sys Adm
TURKIYE

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