On my machine when I was locking my dual-screen-gnome-screen, the left "nav-bar" and the top gnome bar were still viewable. Everything else went black, the super-key was also working and opening the unity menu!
In the Unity Menu I was able to open Firefox! You can't search in the bar, but the visible most-used application are clickable there! The Buttons on the left bar are not clickable.
For sure it's ought to black out both screens completely on lock.
ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: xorg 1:7.6~3ubuntu11
ProcVersionSignature: Ubuntu 2.6.38-5.32-generic 2.6.38-rc6
Uname: Linux 2.6.38-5-generic x86_64
NonfreeKernelModules: nvidia
.proc.driver.nvidia.gpus.0: Error: [Errno 21] Is a directory: '/proc/driver/nvidia/gpus/0'
.proc.driver.nvidia.registry: Binary: ""
.proc.driver.nvidia.version:
NVRM version: NVIDIA UNIX x86_64 Kernel Module 270.29 Wed Feb 23 16:18:35 PST 2011
GCC version: gcc version 4.5.2 (Ubuntu/Linaro 4.5.2-3ubuntu3)
Architecture: amd64
CompizPlugins: [core,bailer,detection,composite,opengl,decor,mousepoll,vpswitch,regex,animation,snap,expo,move,compiztoolbox,place,grid,imgpng,gnomecompat,wall,ezoom,workarounds,staticswitcher,resize,fade,unitymtgrabhandles,scale,session,unityshell]
CompositorRunning: compiz
Date: Sat Mar 5 12:40:43 2011
DistUpgraded: Log time: 2011-03-03 19:30:36.779892
DistroCodename: natty
DistroVariant: ubuntu
DkmsStatus: nvidia-current, 270.29, 2.6.38-5-generic, x86_64: installed
GraphicsCard:
nVidia Corporation G96 [GeForce GT 120] [10de:0646] (rev a1) (prog-if 00 [VGA controller])
Subsystem: Micro-Star International Co., Ltd. Device [1462:a330]
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Alpha amd64 (20110301)
JockeyStatus: xorg:nvidia_current - NVIDIA accelerated graphics driver (Proprietary, Enabled, In use)
MachineType: HP-Pavilion NQ858AA-ABD a6758de
ProcEnviron:
LANGUAGE=en_US:en
LANG=en_US.UTF-8
SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.38-5-generic root=UUID=2659f4cd-a5e6-4af3-82ae-731da976dd83 ro quiet splash vt.handoff=7
Renderer: Unknown
SourcePackage: xorg
Symptom: display
UpgradeStatus: Upgraded to natty on 2011-03-04 (0 days ago)
dmi.bios.date: 05/06/2009
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 5.39
dmi.board.name: Benicia
dmi.board.vendor: PEGATRON CORPORATION
dmi.board.version: 1.01
dmi.chassis.asset.tag: Asset-1234567890
dmi.chassis.type: 3
dmi.chassis.vendor: Hewlett-Packard
dmi.chassis.version: Chassis Version
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr5.39:bd05/06/2009:svnHP-Pavilion:pnNQ858AA-ABDa6758de:pvr:rvnPEGATRONCORPORATION:rnBenicia:rvr1.01:cvnHewlett-Packard:ct3:cvrChassisVersion:
dmi.product.name: NQ858AA-ABD a6758de
dmi.sys.vendor: HP-Pavilion
version.compiz: compiz 1:0.9.4-0ubuntu3
version.libdrm2: libdrm2 2.4.23-1ubuntu3
version.libgl1-mesa-glx: libgl1-mesa-glx 7.10.1~git20110215.cc1636b6-0ubuntu2
version.nvidia-graphics-drivers: nvidia-graphics-drivers N/A
version.xserver-xorg: xserver-xorg 1:7.6~3ubuntu11
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.0-0ubuntu2
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.14.0-4ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20110107+b795ca6e-0ubuntu5
Thanks for your bug report. Are you still facing this issue? a similar bug was fixed a few weeks ago and I think the issue should not happen anymore.