KDE Lockscreen unsresponsive

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1

I prefer to keep my computer running at all times and dislikes having to shut it down or restart it.
When I am away from my computer(work) I invoke the KDE lockscreen (CTRL+ALT+L). Usually I have no problem with it.
However when the computer has been locked for a long period(weekend), it does not respond when I try to wake it up. Nothing responds. Its a black screen and no keyboard shortcuts work(screensaver is also just a black screen, perhaps changing it can fix the problem). The only thing I can do is to manually force my computer to power down.

Anyone know how I can solve this problem? I need to use the lockscreen, but does not want to shut down the computer after each day.

Don’t know if it has anything to do with this, but logging in is through Windows Domain.
Also my computer is a laptop sitting in a docking station with an extra monitor attached. Neither the USB keyboard/mouse nor the laptop keyboard/mouse works.
Detaching it from the docking station doesn’t work either.

2

DJViking wrote:
> Anyone know how I can solve this problem? I need to use the lockscreen,
> but does not want to shut down the computer after each day.

In order to fix it, it may help to diagnose the problem some more. In
order to do that it might be worth logging in to your laptop from
another rmachine over the network using ssh. Then just leave that
session open when you go home.

When you come back and the laptop is unresponsive you may find that you
can still execute commands via the ssh session. If so, you can
investigate what the cause of your problem is - people can make
suggestions if you’re unsure what to do.

On the other hand, if the ssh session is also not responding, it tells
you that the problem may be at a lower level and some other questions
may be asked.

3

If you can login via ssh, then su to root in the ssh session, and kill the Xorg process. See if that gets things working again.

The chances are that you have a video driver problem.

4

It has now become worse. Can’t even keep my computer locked from day to day.

Cannot SSH in, because the computer is not accessible through the network.

5

I think @nrickert has a valid point. But there’s also power management options, that could be related. Check /var/log/messages if you can find any messages about the Xserver dying, or the system changing power management state.

6

Will check my video driver. (Be back with this when I check under Windows whats there…)

As for the power management. While on AC power the screen should power down after 15 minutes. Any hibernation is disabled.

There is nothing in /var/log/messages for previous boot cycles. After I force shutdown og power up, the content of this file from previous is gone.

7

Been away to long (not long actually) and cannot edit my last post…

Have Intel HD Graphics on my Fujitsu Lifebook S761.
Intel VGA Compatible controller
modprobe: i915

How can I check if its the right graphics driver and if not change it?

8

Tried not to lock KDE this last time. Back on after sitting idle for 18 hours and the screen had been powered down, but the computer(KDE) woke up without problems.

Wondering if i should report a bug in KDE lockscreen for this.

9

It’s not a KDE bug, it’s a DPMS issue. Essentially the monitor will turn itself off but won’t turn itself back on which is why you see the black screen, but no response, and I’ve heard of this happening in windows too. So for all intents and purposes it’s a hardware issue. You can typically solve this by telling X not to dpms, via


xset -dpms

and this needs to be run every time you log in, or resume from a suspend.

And it occurring randomly is to be expected for this issue as we’re looking at essentially a hardware bug.

10

I disabled the powersaving mode in KDE before I locked my session last time. It seem like it did the trick.

If it is just the monitor that will not wake up, why was I not able to access the machine through SSH?

I do not have any suspend/hibernation enabled, even when powersaving mode is enabled.

11

The thing is. I don’t want to disable powersaving. My computer is a laptop and I consider powersaving crucial. The only situation where I do not need suspend/hibernation is when connected to power.

12

My laptop has Intel graphics (uses i915 driver).

When it locks up, the entire computer freezes. Even the ethernet card does not respond to arp queries.

I currently disable screen dimming, which helps a lot. Screen blanking, shutting off the screen, does not seem to be a problem. But changing the screen brightness can cause a freeze.

I mostly use connected to power, so I don’t know whether hibernation or suspend causes problems. I seem to recall configuring it to shutdown, rather than hibernate, if idle while on battery.

13

I am also using i915 driver. In my case suspend session is disabled. I have now also disabled screen dimming and screen blanking, while still keeping turn off screen after 15 minutes. Screen dimming does not work on my secondary screen (which is actually my primary screen) anyway.

14

What just happened to my update post. Its removed…

Anyway:
After a while I noticed the problem was gone. I had no longer problem with locking my KDE session and waking up my computer the next day.

My KDE power saving options is, Suspend session with lock screen after 5 minutes and turning off screen after 15 minutes.

After many KDE 4.10 updates the problem went away. Then I upgraded to KDE 4.11 and the problem came back. Considering that, I do not think it is a hardware problem or a graphic driver problem. It must be somewhere in the KDE power saving.

15

When I first had the problem, I experimented. Freezing was actually more likely in Gnome (that was Gnome 3) than in KDE. I don’t think I ever had a freeze problem when running XFCE or icewm.

So it’s not just KDE.

It really could not be KDE if the system completely locking up. A bug in KDE could possibly cause looping and poor response, but it could not cause a lockup. A lockup requires something happening at the system level (such as in a device driver). KDE and Gnome might be more prone to trigger the bug, but the bug is not in KDE or Gnome.

I have not yet used KDE 4.11 extensively enough. Actually, I don’t have it on my system that freezes, but I do have KDE 10.97 (a release candidate for 4.11). Perhaps I’ll experiment a bit more with that.