This happens on my laptop when using additional monitor.
I think that there also may be xorg-intel-driver involved but I can see no information in syslog nor xorg.log.
I'm attaching some screenshots of unity desktop.
ProblemType: KernelOops
DistroRelease: Ubuntu 11.04
Package: linux-image-2.6.38-6-generic 2.6.38-6.34
Regression: No
Reproducible: Yes
ProcVersionSignature: Ubuntu 2.6.38-6.34-generic 2.6.38-rc7
Uname: Linux 2.6.38-6-generic x86_64
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.23.
Annotation: Your system might become unstable now and might need to be restarted.
Architecture: amd64
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/controlC0: Slmodemd 1378 F.... slmodemd
matusikk 5892 F.... pulseaudio
/dev/snd/pcmC0D6c: Slmodemd 1378 F.... slmodemd
/dev/snd/pcmC0D6p: Slmodemd 1378 F.... slmodemd
Card0.Amixer.info:
Card hw:0 'Intel'/'HDA Intel at 0xe8580000 irq 44'
Mixer name : 'Analog Devices AD1981'
Components : 'HDA:11d41981,103c30aa,00100200 HDA:11c13026,103c30aa,00100700'
Controls : 13
Simple ctrls : 11
Date: Thu Mar 17 09:49:27 2011
Failure: oops
HibernationDevice: RESUME=UUID=8a029044-6ad2-4766-8699-bbdb4ecec430
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Alpha amd64 (20100803.1)
PccardctlIdent:
Socket 0:
no product info available
PccardctlStatus:
Socket 0:
no card
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.38-6-generic root=UUID=ae1b442f-c06a-4626-ab65-d11f01735f1e ro quiet splash vt.handoff=7
RelatedPackageVersions:
linux-restricted-modules-2.6.38-6-generic N/A
linux-backports-modules-2.6.38-6-generic N/A
linux-firmware 1.48
SourcePackage: linux
Title: BUG: unable to handle kernel NULL pointer dereference at 0000000000000230
UpgradeStatus: Upgraded to natty on 2010-12-07 (100 days ago)
dmi.bios.date: 02/21/2008
dmi.bios.vendor: Hewlett-Packard
dmi.bios.version: 68YDU Ver. F.0E
dmi.board.name: 30AA
dmi.board.vendor: Hewlett-Packard
dmi.board.version: KBC Version 58.13
dmi.chassis.asset.tag: CNU6412FYD
dmi.chassis.type: 10
dmi.chassis.vendor: Hewlett-Packard
dmi.modalias: dmi:bvnHewlett-Packard:bvr68YDUVer.F.0E:bd02/21/2008:svnHewlett-Packard:pn:pvrF.0E:rvnHewlett-Packard:rn30AA:rvrKBCVersion58.13:cvnHewlett-Packard:ct10:cvr:
dmi.product.version: F.0E
dmi.sys.vendor: Hewlett-Packard
