kernel panic when changing brightness

[Ryan Kitty]

This is the first time this has ever happened. I am using Ubuntu 10.04 LTS with both the original shipped kernel, and the updated kernel in the repo. I don't remember the version off the top of my head, though. Anyway, the kernel panics whenever I change the screen brightness on my lappy. This has never happened before using this or any other version of Ubuntu. I first experienced this issue with Linux Mint 9, so I wiped out my Linux partition and installed Ubuntu 10.04LTS. the issue is still there. Every time i switch the brightness, I get a frozen laptop with the message Glib-WARNING: getpwuid_r() failed due to unknown user id (0). Now that I think about this, that doesn't seem to be related, but i know nothing about the Kernel itself. If you need more details or debug files, please let me know which ones you need, and I will be happy to provide you with them.

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: linux-image-2.6.32-22-generic 2.6.32-22.36
Regression: No
Reproducible: No
ProcVersionSignature: Ubuntu 2.6.32-22.36-generic 2.6.32.11+drm33.2
Uname: Linux 2.6.32-22-generic i686
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.21.
Architecture: i386
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: ryan 2205 F.... pulseaudio
 /dev/snd/pcmC0D0p: ryan 2205 F...m pulseaudio
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
 Card hw:0 'SB'/'HDA ATI SB at 0xb0000000 irq 16'
   Mixer name : 'SigmaTel STAC9250'
   Components : 'HDA:83847634,107b0367,00100101 HDA:10573057,00010001,00100100'
   Controls : 9
   Simple ctrls : 7
Date: Sat Jun 12 14:45:19 2010
EcryptfsInUse: Yes
Frequency: Once a day.
HibernationDevice: RESUME=UUID=948c66f8-6fe0-4d23-afe6-996a1e79512f
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release i386 (20100429)
Lsusb:
 Bus 003 Device 002: ID 045e:00e3 Microsoft Corp.
 Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: Gateway MT6458
PccardctlIdent:
 Socket 0:
   no product info available
PccardctlStatus:
 Socket 0:
   no card
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.32-22-generic root=UUID=5b73989b-45f8-4d74-96db-6252bfb38d14 ro quiet splash
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
RelatedPackageVersions: linux-firmware 1.34.1
RfKill:

SourcePackage: linux
dmi.bios.date: 11/27/2006
dmi.bios.vendor: Phoenix Technologies LTD
dmi.bios.version: 84.06
dmi.board.vendor: Gateway
dmi.board.version: 84.06
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 8
dmi.chassis.vendor: Gateway
dmi.chassis.version: Rev.1
dmi.modalias: dmi:bvnPhoenixTechnologiesLTD:bvr84.06:bd11/27/2006:svnGateway:pnMT6458:pvr3408447R:rvnGateway:rn:rvr84.06:cvnGateway:ct8:cvrRev.1:
dmi.product.name: MT6458
dmi.product.version: 3408447R
dmi.sys.vendor: Gateway

[Ryan Kitty (gothickitty93)]

Oh, and I have already tested the upstream kernel, and that one won't even boot. It just turns off the LCD and no hard drive activity occurs.

[Jeremy Foshee (jeremyfoshee)]

Hi Ryan,

If you could also please test the latest upstream kernel available that would be great. It will allow additional upstream developers to examine the issue. Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Once you've tested the upstream kernel, please remove the 'needs-upstream-testing' tag. This can be done by clicking on the yellow pencil icon next to the tag located at the bottom of the bug description and deleting the 'needs-upstream-testing' text. Please let us know your results.

Thanks in advance.

    [This is an automated message. Apologies if it has reached you inappropriately; please just reply to this message indicating so.]

[Ryan Kitty (gothickitty93)]

As I previously posted, I already tested the upstream kernel. It does not even boot past grub. It just shuts off the LCD screen and sits there. The new upstream I tested wouldn't complete booting because it panicked even before I changed the brightness. Unfortunatly, I cannot provide logs or debug info for this bug anymore because I am trying to get my computer to work again, so I no longer have this instance of Ubuntu 10.04 installed. (FYI everything works fine in Fedora, at least screen brightness wise.)

[Ryan Kitty (gothickitty93)]

I have found the issue (I think) on my computer. I changed the display settings in my BIOS from CRT to LCD+CRT. That, and a fresh install of Ubuntu 10.04LTS, everything works just fine. I'm gonna take a guess and say that the panic should not occur no matter which mode it is in, so I will leave this bug report open until it expires automatically. Thanks for the great support community!

Ryan S.