kernel BUG at /build/buildd/linux-2.6.38/fs/ecryptfs/crypto.c:349!; EIP is at encrypt_scatterlist+0xe4/0x120

i think xorg crashed? screen hang and i just saw text (cli), mouse was still visible.

ProblemType: KernelOops
DistroRelease: Ubuntu 11.04
Package: linux-image-2.6.38-8-generic-pae 2.6.38-8.42
Regression: Yes
Reproducible: No
ProcVersionSignature: Ubuntu 2.6.38-8.42-generic-pae 2.6.38.2
Uname: Linux 2.6.38-8-generic-pae i686
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
ArecordDevices:
 **** List of CAPTURE Hardware Devices ****
 card 0: Intel [HDA Intel], device 0: ALC662 rev1 Analog [ALC662 rev1 Analog]
   Subdevices: 0/1
   Subdevice #0: subdevice #0
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: raimond 1916 F.... pulseaudio
 /dev/snd/pcmC0D0c: raimond 1916 F...m pulseaudio
 /dev/snd/pcmC0D0p: raimond 1916 F...m pulseaudio
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
 Card hw:0 'Intel'/'HDA Intel at 0xfdef4000 irq 47'
   Mixer name : 'Intel Cantiga HDMI'
   Components : 'HDA:10ec0662,10431833,00100101 HDA:80862802,80860101,00100000'
   Controls : 20
   Simple ctrls : 9
Date: Sat Apr 16 15:28:23 2011
Failure: oops
Frequency: This has only happened once.
HibernationDevice: RESUME=UUID=e307c480-89e0-4dd6-bdfa-9b958f195f9d
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release i386 (20101007)
MachineType: ASUSTeK Computer Inc. X71Q
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.38-8-generic-pae root=UUID=7437807f-70ad-4a7e-8afc-f0ff487a7a04 ro quiet splash acpi_backlight=vendor vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-2.6.38-8-generic-pae N/A
 linux-backports-modules-2.6.38-8-generic-pae N/A
 linux-firmware 1.50
RfKill:
 0: phy0: Wireless LAN
  Soft blocked: no
  Hard blocked: no
SourcePackage: linux
Title: kernel BUG at /build/buildd/linux-2.6.38/fs/ecryptfs/crypto.c:349!
UpgradeStatus: Upgraded to natty on 2011-04-02 (13 days ago)
dmi.bios.date: 06/05/2009
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 205
dmi.board.asset.tag: ATN12345678901234567
dmi.board.name: X71Q
dmi.board.vendor: ASUSTeK Computer Inc.
dmi.board.version: 1.0
dmi.chassis.asset.tag: ATN12345678901234567
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTeK Computer Inc.
dmi.chassis.version: 1.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr205:bd06/05/2009:svnASUSTeKComputerInc.:pnX71Q:pvr1.0:rvnASUSTeKComputerInc.:rnX71Q:rvr1.0:cvnASUSTeKComputerInc.:ct10:cvr1.0:
dmi.product.name: X71Q
dmi.product.version: 1.0
dmi.sys.vendor: ASUSTeK Computer Inc.