Slack 13.1 Framebuffer problem

erraticassassin · 09-23-2010, 01:40 PM

Hi chaps,

This is my first post on LQ for ages, mostly because I've been happily running 12.2 on several laptops and desktops for a good long while without any problems.

However... I don't like to get too far behind the curve, so I tried upgrading my main desktop to 13.1. Installation went fine, as usual, but on rebooting, the framebuffer changes resolution mid-boot. The text ends up tiny, and the display seems to be resized so it's too large to fit the monitor. The boot messages relevant to the problem seem to be these:

Code:

fb: conflicting fb he usage inteldrmfb vs VESA VGA - removing generic driver
console: switching to color dummy device 80x25
console: switching to color framebuffer device 160x64

The desktop in question is a Lenovo Thinkcenter, model unknown, using the Intel 946GZ Express chipset.

Any thoughts?

clw54 · 09-23-2010, 01:47 PM

I ran into the same thing on my HP laptop. It can also cause the screen to go blank. You can get rid of it by putting this in LILO.

append = "nomodeset"

The trouble is you can't use X anymore. Maybe somebody has come up with a fix recently, but I spent a lot of time Googling and searching this forum for an answer. I finally went back to 12.2, which ran very well on my laptop. If you solve it, please let us know how you did it.

erraticassassin · 09-23-2010, 01:51 PM

Quote:

Originally Posted by clw54

The trouble is you can't use X anymore.

Ha. I won't be doing that, then.

It's an annoying problem because it's very rare, in my experience, to run into this sort of thing with Slackware...

clw54 · 09-23-2010, 02:05 PM

I was going to live with it until I started getting a blank screen instead of the framebuffer. It has something to do with kernel mode setting, where the kernel takes over responsibilities that were previously with X. Nomodeset turns that off. Google kernel mode setting and it will turn up a lot of information. I'm hoping they'll find a way to leave the console alone. I like a regular VGA console.

piratesmack · 09-23-2010, 02:30 PM

You can change the resolution with the 'video' boot parameter.

e.g.

Code:

append = "video=640x480"

Also, here is something ugly I did on my computer so I don't see the resolution change during boot:

Blacklist the i915 module:

Code:

echo "blacklist i915" > /etc/modprobe.d/BLACKLIST-i915.conf

Then edit /etc/rc.d/rc.4 so it loads i915 right before X starts:

Code:

# Tell the viewers what's going to happen...
echo "Starting up X11 session manager..."


chvt 2
modprobe i915

*Note: that's assuming your using runlevel 4 as default. For runlevel 3, you can load i915 in ~/.xinitrc or something.
*Also, substitute i915 with a different module if you don't use it.

oldfolio · 09-23-2010, 02:51 PM

Piratesmack's solution has the advantage of allowing you to keep framebuffering. So, if that works for you, I'd go with it. If you'd really like to disable framebuffering altogether, this was a crude solution that worked for me.

1. Created file /etc/modprobe.d/i915.conf with the line:

Code:

options i915 modeset=0

(Obviously, if you're not using the i915 module, you'd edit accordingly.)

2. I then created a minimal /etc/X11/xorg.conf file to load the vesa driver (because otherwise I got the black screen of death):

Code:

Section "Device"
    Identifier "Configured Video Device"
    Driver "vesa"
EndSection

Section "Monitor"
    Identifier "Configured Monitor"
EndSection

Section "Screen"
    Identifier "Default Screen"
    Monitor "Configured Monitor"
    Device "Configured Video Device"
EndSection

erraticassassin · 09-24-2010, 04:19 PM

Cheers, chaps. I've played around with piratesmack's suggestion and it seems like a decent workaround, in that it makes the problem less visible and allows X to work, so I think that's a sort-of-win.

I'm assuming at this point that the problem is limited to Intel chipsets, because I installed 13.1 on an old laptop with ATI video before I installed it on my Thinkcenter, and it worked fine... which raises the question of why, if the problem is limited to Intel gear, hasn't it been picked up and solved already? It's not like Intel is an obscure manufacturer...

Thanks again for the assistance, anyways!

piratesmack · 09-25-2010, 02:24 AM

Here is one more thing you can try.

Downgrade to xf86-video-intel-2.9.x (This was the last version that didn't require KMS) and boot with nomodeset

Forum member Gapan has built packages:
http://www.linuxquestions.org/questi...9/#post3982112

erraticassassin · 09-25-2010, 08:16 AM

Well... looks like it might be time to try the older drivers. I now seem to be getting random shut-downs, presumably down to X crashing?

On the plus side, my graphics tablet now seems to be recognised without any faffing around, so assuming I can ever sort out the video problem that'll be a bonus!

Piratesmack - how to I go about installing/configuring the older driver?

piratesmack · 09-25-2010, 08:47 AM

Quote:

Originally Posted by erraticassassin

Well... looks like it might be time to try the older drivers. I now seem to be getting random shut-downs, presumably down to X crashing?

KMS was also very unstable for me with the 2.6.33 kernel.
It seems to be OK with 2.6.34+, though. So maybe if downgrading xf86-video-intel doesn't work, then upgrading your kernel is worth a shot.

Quote:

Piratesmack - how to I go about installing/configuring the older driver?

I don't think any special configuration is necessary.
Just download the package and downgrade with:

Code:

# upgradepkg xf86-video-intel-2.9.1-i486-1gv.txz

Then restart X

Slackware doesn't care about version numbers, so you can downgrade the same way you upgrade.

clw54 · 09-25-2010, 12:14 PM

Thank you, Piratesmack! I put 13.1 back on my HP laptop and used the 2.9.1 driver. upgradepkg did the trick. I now have VGA at the console and X works.

For the record, lspci shows I have an Intel Corporation Moble GM965/GL960 Integrated Graphics Controller using the i915 module. Hopefully the keywords will bring anybody with the same problem here.

My lilo.conf has this line:

# Append any additional kernel parameters:
Append="nomodeset vt.default_utf8=0"

I didn't need to blacklist i915.

Thanks again.

erraticassassin · 09-25-2010, 05:57 PM

Well... looks like it's back to 12.2 tomorrow.

Having tried the various options, none of them work reliably enough and well enough that I'm happy to use them. Using the older driver looked promising, but logging out leads to a blank screen rather than the KDE login manager; booting to runlevel 3 and starting X manually doesn't help, as attempting to logout leads to blank screens again. The various methods of camouflaging the ugly boot resolution change can't get around the fact that once I get to a desktop, there are still random shutdowns/resolution problems to deal with.

Disappointed doesn't quite cover it.

piratesmack · 09-25-2010, 06:53 PM

Quote:

Originally Posted by erraticassassin

Using the older driver looked promising, but logging out leads to a blank screen rather than the KDE login manager

Try adding this to /etc/kde/kdm/kdmrc:

Code:

TerminateServer=true

May require a reboot

titopoquito · 09-26-2010, 06:05 AM

I'm starting in runlevel 3, so I cannot say something about kdm. I had initial problems too with the framebuffer, but it is running perfectly so far with the newest kernel 2.6.35.5 and the stock Slackware 13.1 packages (I used the generic kernel config file Robby Workman posted in the xorg-testing thread). I've built an initrd.gz file which contains the i915 module and now the KMS switches before I have to edit a password to unlock my LUKS encrypted root partition and remains in this setting right up to the login.
Before that, the switch didn't work correctly and I got a blank black login screen. Typing in the login and password blindly and after that "startx" made the screen become visible though.

My graphics card is listed by lspci as

Code:

00:02.0 VGA compatible controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 03)
00:02.1 Display controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 03)

so I think this could be relevant to your problem.

erraticassassin · 09-26-2010, 08:35 AM

Thanks for your assistance, chaps, but as there's no "must have" in 13.1, I'm cutting my losses and reverting to 12.2 for my main desktop box.