Intel SNA garbled screen when detaching from the docking station

[Martin Vysny]

I have the Dell E6510 laptop with the following Intel VGA: "Core Processor Integrated Graphics Controller [8086:0046] (rev 02)". The laptop sits docked in the docking station. An external 1920x1200 monitor is connected via the docking station's DisplayPort. I have configured the laptop's display (eDP1) to be disabled while docked, as shown in xrandr:

$ xrandr
Screen 0: minimum 320 x 200, current 1920 x 1200, maximum 8192 x 8192
eDP1 connected (normal left inverted right x axis y axis)
   1600x900 60.0 + 40.0
   1440x900 59.9
   1360x768 59.8 60.0
   1152x864 60.0
   1024x768 60.0
   800x600 60.3 56.2
   640x480 59.9
VGA1 disconnected (normal left inverted right x axis y axis)
HDMI1 disconnected (normal left inverted right x axis y axis)
DP1 disconnected (normal left inverted right x axis y axis)
HDMI2 disconnected (normal left inverted right x axis y axis)
HDMI3 disconnected (normal left inverted right x axis y axis)
DP2 disconnected (normal left inverted right x axis y axis)
DP3 connected 1920x1200+0+0 (normal left inverted right x axis y axis) 518mm x 324mm
   1920x1200 60.0*+
   1920x1080 60.0
   1600x1200 60.0
   1680x1050 60.0
   1280x1024 60.0
   1440x900 59.9
   1280x960 60.0
   1024x768 60.0
   800x600 60.3
   640x480 60.0

When the SNA is enabled and the notebook is ejected from the docking station, the screen becomes garbled on the internal screen (please see attachment for a screenshot). When I switch to old UXA using the following xorg.conf:

$ cat /etc/X11/xorg.conf
Section "Device"
  Identifier "Card0"
  Driver "intel"
  Option "AccelMethod" "uxa"
EndSection

the laptop detachment works flawlessly and the screen is not garbled.

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: xorg 1:7.7+1ubuntu4
ProcVersionSignature: Ubuntu 3.8.0-18.28-generic 3.8.6
Uname: Linux 3.8.0-18-generic i686
.tmp.unity.support.test.0:

ApportVersion: 2.9.2-0ubuntu8
Architecture: i386
CompizPlugins: [core,composite,opengl,decor,move,regex,gnomecompat,vpswitch,mousepoll,resize,place,grid,compiztoolbox,snap,imgpng,unitymtgrabhandles,session,animation,workarounds,wall,expo,ezoom,fade,scale,unityshell]
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW: true
Date: Thu Apr 18 09:20:49 2013
DistUpgraded: 2013-04-12 09:14:34,410 DEBUG enabling apt cron job
DistroCodename: raring
DistroVariant: ubuntu
DkmsStatus:
 virtualbox, 4.2.10, 3.8.0-17-generic, i686: installed
 virtualbox, 4.2.10, 3.8.0-18-generic, i686: installed
EcryptfsInUse: Yes
ExtraDebuggingInterest: Yes, if not too technical
GraphicsCard:
 Intel Corporation Core Processor Integrated Graphics Controller [8086:0046] (rev 02) (prog-if 00 [VGA controller])
   Subsystem: Dell Device [1028:040b]
InstallationDate: Installed on 2010-05-17 (1066 days ago)
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release i386 (20100429)
MachineType: Dell Inc. Latitude E6510
MarkForUpload: True
PccardctlIdent:
 Socket 0:
   no product info available
PccardctlStatus:
 Socket 0:
   no card
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.8.0-18-generic root=UUID=02dfb985-99c1-431d-882f-87475db02062 ro crashkernel=384M-2G:64M,2G-:128M splash elevator=noop
SourcePackage: xorg
UpgradeStatus: Upgraded to raring on 2013-04-12 (6 days ago)
XorgConf:
 Section "Device"
   Identifier "Card0"
   Driver "intel"
   Option "AccelMethod" "uxa"
 EndSection
dmi.bios.date: 11/20/2010
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A06
dmi.board.name: 02K3Y4
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 9
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA06:bd11/20/2010:svnDellInc.:pnLatitudeE6510:pvr0001:rvnDellInc.:rn02K3Y4:rvrA00:cvnDellInc.:ct9:cvr:
dmi.product.name: Latitude E6510
dmi.product.version: 0001
dmi.sys.vendor: Dell Inc.
version.compiz: compiz 1:0.9.9~daily13.04.15-0ubuntu1
version.libdrm2: libdrm2 2.4.43-0ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 9.1.1-0ubuntu2
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 9.1.1-0ubuntu2
version.xserver-xorg-core: xserver-xorg-core 2:1.13.3-0ubuntu6
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.3-0ubuntu2b2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.1.0-0ubuntu2
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.21.6-0ubuntu3
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.7-0ubuntu1

[Martin Vysny (vyzivus)]

Proof that SNA was enabled during previous Xorg start:
$ sudo grep SNA Xorg.*
Xorg.0.log.old:[ 461.127] (II) intel(0): SNA compiled: xserver-xorg-video-intel 2:2.21.6-0ubuntu3 (Bryce Harrington <email address hidden>)
Xorg.0.log.old:[ 461.549] (II) intel(0): SNA initialized with Ironlake backend

Proof that UXA is enabled now:
$ sudo grep UXA Xorg.*
Xorg.0.log:[ 582.860] (II) UXA(0): Driver registered support for the following operations:

[Martin Vysny (vyzivus)]

Xorg logs

[Martin Vysny (vyzivus)]

Xorg SNA log

[Martin Vysny (vyzivus)]

Note that the issue manifested three times out of three docking station detachments.

[Chris Wilson (ickle)]

The bug here is a pageflipping vs modesetting race in the kernel.

[Martin Vysny (vyzivus)]

Thank you very much, the newest xorg-intel 2:2.21.6-0ubuntu4 fixes the issue for me. Thanks again :)