kernel BUG at /build/buildd/linux-2.6.38/fs/btrfs/disk-io.c:2349!

[joshua pritikin]

Power lost to external USB drive with a btrfs filesystem mounted.

ProblemType: KernelOops
DistroRelease: Ubuntu 11.04
Package: linux-image-2.6.38-8-generic 2.6.38-8.42
ProcVersionSignature: Ubuntu 2.6.38-8.42-generic 2.6.38.2
Uname: Linux 2.6.38-8-generic 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
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: joshua 1895 F.... pulseaudio
 /dev/snd/pcmC0D0p: joshua 1895 F...m pulseaudio
 /dev/snd/seq: timidity 1673 F.... timidity
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
 Card hw:0 'Intel'/'HDA Intel at 0xfe9fc000 irq 47'
   Mixer name : 'SigmaTel STAC9228'
   Components : 'HDA:83847616,102801f3,00100201 HDA:14f12c06,14f1000f,00100000'
   Controls : 27
   Simple ctrls : 18
Date: Fri Jul 8 11:11:03 2011
Failure: oops
HibernationDevice: RESUME=UUID=e65c7d03-85ba-4246-b299-2fb76a755ec9
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Beta i386 (20110413)
MachineType: Dell Inc. Inspiron 1420
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-2.6.38-8-generic root=/dev/mapper/jvg-natty32 ro rootflags=subvol=@ quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-2.6.38-8-generic N/A
 linux-backports-modules-2.6.38-8-generic N/A
 linux-firmware 1.52
SourcePackage: linux
Title: kernel BUG at /build/buildd/linux-2.6.38/fs/btrfs/disk-io.c:2349!
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 02/03/2008
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A07
dmi.board.name: 0DT492
dmi.board.vendor: Dell Inc.
dmi.chassis.type: 8
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA07:bd02/03/2008:svnDellInc.:pnInspiron1420:pvr:rvnDellInc.:rn0DT492:rvr:cvnDellInc.:ct8:cvr:
dmi.product.name: Inspiron 1420
dmi.sys.vendor: Dell Inc.