BUG: unable to handle kernel NULL pointer dereference at (null)

[Massimiliano Forner]

It happend at every start/restart of the system.

ProblemType: KernelOops
DistroRelease: Ubuntu 11.04
Package: linux-image-2.6.38-7-generic 2.6.38-7.39
Regression: Yes
Reproducible: Yes
ProcVersionSignature: Ubuntu 2.6.38-7.39-generic 2.6.38
Uname: Linux 2.6.38-7-generic i686
NonfreeKernelModules: openafs nvidia
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.23.
Annotation: Your system might become unstable now and might need to be restarted.
Architecture: i386
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: massimiliano 4058 F.... pulseaudio
Card0.Amixer.info:
 Card hw:0 'Intel'/'HDA Intel at 0xf8400000 irq 47'
   Mixer name : 'Realtek ALC268'
   Components : 'HDA:10ec0268,103c30cc,00100003 HDA:10573055,10573055,00100700'
   Controls : 21
   Simple ctrls : 13
Date: Wed Mar 30 15:58:29 2011
Failure: oops
HibernationDevice: RESUME=UUID=40cb1a91-6429-4fa6-8f5b-8952fe377fc2
MachineType: Hewlett-Packard HP Pavilion dv6500 Notebook PC
ProcKernelCmdLine: root=UUID=e069f758-844f-4aa6-8530-6df59c525938 ro quiet splash vga=792
RelatedPackageVersions:
 linux-restricted-modules-2.6.38-7-generic N/A
 linux-backports-modules-2.6.38-7-generic N/A
 linux-firmware 1.49
SourcePackage: linux
Title: BUG: unable to handle kernel NULL pointer dereference at (null)
UpgradeStatus: Upgraded to natty on 2011-03-29 (0 days ago)
WpaSupplicantLog:

dmi.bios.date: 10/03/2007
dmi.bios.vendor: Hewlett-Packard
dmi.bios.version: F.23
dmi.board.name: 30D2
dmi.board.vendor: Quanta
dmi.board.version: 79.22
dmi.chassis.type: 10
dmi.chassis.vendor: Quanta
dmi.chassis.version: N/A
dmi.modalias: dmi:bvnHewlett-Packard:bvrF.23:bd10/03/2007:svnHewlett-Packard:pnHPPaviliondv6500NotebookPC:pvrRev1:rvnQuanta:rn30D2:rvr79.22:cvnQuanta:ct10:cvrN/A:
dmi.product.name: HP Pavilion dv6500 Notebook PC
dmi.product.version: Rev 1
dmi.sys.vendor: Hewlett-Packard