WARNING: at /build/buildd/linux-2.6.38/drivers/gpu/drm/radeon/radeon_fence.c:248 radeon_fence_wait+0x36f/0x3e0 [radeon]()

[Renji]

was installing addons in firefox when alt tab caused this error

ProblemType: KernelOops
DistroRelease: Ubuntu 11.04
Package: linux-image-2.6.38-7-generic 2.6.38-7.39
Regression: Yes
Reproducible: No
ProcVersionSignature: Ubuntu 2.6.38-7.39-generic 2.6.38
Uname: Linux 2.6.38-7-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
ArecordDevices:
 **** List of CAPTURE Hardware Devices ****
 card 0: PCH [HDA Intel PCH], device 0: ALC892 Analog [ALC892 Analog]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: renji 1451 F.... pulseaudio
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
 Card hw:0 'PCH'/'HDA Intel PCH at 0xfe720000 irq 55'
   Mixer name : 'Realtek ALC892'
   Components : 'HDA:10ec0892,80862005,00100302'
   Controls : 32
   Simple ctrls : 18
Card1.Amixer.info:
 Card hw:1 'Generic'/'HD-Audio Generic at 0xfe640000 irq 56'
   Mixer name : 'ATI R6xx HDMI'
   Components : 'HDA:1002aa01,00aa0100,00100200'
   Controls : 4
   Simple ctrls : 1
Card1.Amixer.values:
 Simple mixer control 'IEC958',0
   Capabilities: pswitch pswitch-joined penum
   Playback channels: Mono
   Mono: Playback [on]
Date: Sun Apr 3 14:01:35 2011
Failure: oops
Frequency: This has only happened once.
HibernationDevice: RESUME=UUID=bdbfb0be-4090-48b4-85e8-34aea442d0bd
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release amd64 (20101007)
IwConfig:
 lo no wireless extensions.

 eth0 no wireless extensions.
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.38-7-generic root=UUID=3a977586-1996-4963-9e4f-27d10ec35f70 ro quiet splash vt.handoff=7
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
RfKill:

SourcePackage: linux
Title: WARNING: at /build/buildd/linux-2.6.38/drivers/gpu/drm/radeon/radeon_fence.c:248 radeon_fence_wait+0x36f/0x3e0 [radeon]()
UpgradeStatus: Upgraded to natty on 2011-04-03 (0 days ago)
dmi.bios.date: 10/29/2010
dmi.bios.vendor: Intel Corp.
dmi.bios.version: BAP6710H.86A.0031.2010.1029.1501
dmi.board.asset.tag: To be filled by O.E.M.
dmi.board.name: DP67BA
dmi.board.vendor: Intel Corporation
dmi.board.version: AAG10219-202
dmi.chassis.type: 3
dmi.modalias: dmi:bvnIntelCorp.:bvrBAP6710H.86A.0031.2010.1029.1501:bd10/29/2010:svn:pn:pvr:rvnIntelCorporation:rnDP67BA:rvrAAG10219-202:cvn:ct3:cvr: