Ubuntu
linux package

Dithering regression on Intel graphics with .38 Natty kernel

Bug #711568 reported by Eric Appleman on 2011-02-01

This bug affects 2 people

	Status	Importance	Assigned to	Milestone
Linux	Fix Released	Medium	linux-kernel-bugs #28382
linux (Ubuntu)	Fix Released	High	Andy Whitcroft	Ubuntu natty-alpha-3
xserver-xorg-video-intel (Ubuntu)	Invalid	Undecided	Unassigned

Bug Description

When using the 2.6.38-1 kernel, there is session-wide color banding where gradients would otherwise appear.

This is not present in the earlier Natty kernels.

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: linux-image-2.6.38-1-generic 2.6.38-1.28
Regression: Yes
Reproducible: Yes
ProcVersionSignature: Ubuntu 2.6.38-1.28-genusername 2.6.38-rc2
Uname: Linux 2.6.38-1-generic i686
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.23.
Architecture: i386
ArecordDevices:
**** List of CAPTURE Hardware Devices ****
card 0: Intel [HDA Intel], device 0: STAC92xx Analog [STAC92xx Analog]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/by-path', '/dev/snd/controlC0', '/dev/snd/hwC0D0', '/dev/snd/hwC0D1', '/dev/snd/pcmC0D0c', '/dev/snd/pcmC0D0p', '/dev/snd/pcmC0D1p', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1:
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
Card hw:0 'Intel'/'HDA Intel at 0xefebc000 irq 43'
   Mixer name : 'SigmaTel STAC9200'
   Components : 'HDA:83847690,102801d8,00102201 HDA:14f12bfa,14f100c3,00090000'
   Controls : 11
   Simple ctrls : 6
Date: Tue Feb 1 18:14:24 2011
HibernationDevice: RESUME=UUID=466e3d0b-f906-4658-bf7d-93e428b77230
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Alpha i386 (20101229)
Lsusb:
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: Dell Inc. MXC061
ProcEnviron:
LANGUAGE=en_US:en
LANG=en_US.UTF-8
LC_MESSAGES=en_US.utf8
SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.38-1-genusername root=UUID=6962d6df-ace0-470e-8518-44affc4c8716 ro quiet splash vt.handoff=7
RelatedPackageVersions:
linux-restricted-modules-2.6.38-1-generic N/A
linux-backports-modules-2.6.38-1-generic N/A
linux-firmware 1.46
SourcePackage: linux
dmi.bios.date: 07/10/2007
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A11
dmi.board.vendor: Dell Inc.
dmi.chassis.type: 8
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA11:bd07/10/2007:svnDellInc.:pnMXC061:pvr:rvnDellInc.:rn:rvr:cvnDellInc.:ct8:cvr:
dmi.product.name: MXC061
dmi.sys.vendor: Dell Inc.

Tags:

Revision history for this message

Eric Appleman (erappleman) wrote on 2011-02-01:

AcpiTables.txt Edit (94.3 KiB, text/plain; charset="utf-8")
AlsaDevices.txt Edit (526 bytes, text/plain; charset="utf-8")
AplayDevices.txt Edit (281 bytes, text/plain; charset="utf-8")
BootDmesg.txt Edit (51.6 KiB, text/plain; charset="utf-8")
Card0.Amixer.values.txt Edit (1.1 KiB, text/plain; charset="utf-8")
Card0.Codecs.codec.0.txt Edit (5.8 KiB, text/plain; charset="utf-8")
Card0.Codecs.codec.1.txt Edit (159 bytes, text/plain; charset="utf-8")
CurrentDmesg.txt Edit (58.9 KiB, text/plain; charset="utf-8")
Dependencies.txt Edit (1.8 KiB, text/plain; charset="utf-8")
IwConfig.txt Edit (507 bytes, text/plain; charset="utf-8")
Lspci.txt Edit (12.8 KiB, text/plain; charset="utf-8")
PciMultimedia.txt Edit (595 bytes, text/plain; charset="utf-8")
ProcCpuinfo.txt Edit (1.4 KiB, text/plain; charset="utf-8")
ProcCpuinfo_.txt Edit (1.4 KiB, text/plain; charset="utf-8")
ProcInterrupts.txt Edit (1.6 KiB, text/plain; charset="utf-8")
ProcModules.txt Edit (2.8 KiB, text/plain; charset="utf-8")
RfKill.txt Edit (128 bytes, text/plain; charset="utf-8")
UdevDb.txt Edit (98.9 KiB, text/plain; charset="utf-8")
UdevLog.txt Edit (249.9 KiB, text/plain; charset="utf-8")
WifiSyslog.txt Edit (13.7 MiB, text/plain; charset="utf-8")

Revision history for this message

Bryce Harrington (bryce) wrote on 2011-02-03:

Photo of screen please?

Changed in xserver-xorg-video-intel (Ubuntu):
status:	New → Incomplete

Revision history for this message

Eric Appleman (erappleman) wrote on 2011-02-03: Re: [Bug 711568] Re: Dithering regression on Intel graphics with .38 Natty kernel

On 02/02/2011 07:33 PM, Bryce Harrington wrote:
> Photo of screen please?
>
> ** Changed in: xserver-xorg-video-intel (Ubuntu)
> Status: New => Incomplete
>
I don't even think my brand new 14.1 MP camera can even capture that
level of detail.

I'll make a test image with a gradient and see if I can get a decent shot.

The banding is very subtle unless you have a dark image.

Bryce Harrington (bryce) on 2011-02-04

Changed in xserver-xorg-video-intel (Ubuntu):
status:	Incomplete → New
status:	New → Incomplete

Revision history for this message

Eric Appleman (erappleman) wrote on 2011-02-04:

Reference image of background Edit (201.3 KiB, image/jpeg)

Revision history for this message

Eric Appleman (erappleman) wrote on 2011-02-04:

Displayed image Edit (80.1 KiB, image/jpeg)

Eric Appleman (erappleman) on 2011-02-05

Changed in xserver-xorg-video-intel (Ubuntu):
status:	Incomplete → Confirmed
status:	Confirmed → New

Andy Whitcroft (apw) on 2011-02-07

tags:

added: kernel-key

Revision history for this message

Bryce Harrington (bryce) wrote on 2011-02-07:

drm-intel.git-72389a33b8878e6091f7ab8080f5ed07054c7c39.patch Edit (1.7 KiB, text/plain)

Revision history for this message

Bryce Harrington (bryce) wrote on 2011-02-07:

Fixed upstream by the attached patch.

Kernel team, over to you.

Changed in linux (Ubuntu):
importance:	Undecided → High
milestone:	none → natty-alpha-3
status:	New → Triaged
assignee:	nobody → Jeremy Foshee (jeremyfoshee)

Jeremy Foshee (jeremyfoshee) on 2011-02-07

tags:

added: patch
removed: needs-upstream-testing

Revision history for this message

Bryce Harrington (bryce) wrote on 2011-02-07:

llstarks, thanks for interfacing with upstream directly. Since it's pinpointed to the kernel drm and since we've got a patch now, the kernel team can take it from here.

Changed in xserver-xorg-video-intel (Ubuntu):
status:	New → Invalid

Jeremy Foshee (jeremyfoshee) on 2011-02-07

Changed in linux (Ubuntu):
assignee:	Jeremy Foshee (jeremyfoshee) → nobody

Andy Whitcroft (apw) on 2011-02-07

Changed in linux (Ubuntu):
assignee:	nobody → Andy Whitcroft (apw)

Revision history for this message

Andy Whitcroft (apw) wrote on 2011-02-08:

Ok I have pulled in the commit Bryce suggested and built some test kernels. Could those of you affected please test the kernels at the URL below:

http://people.canonical.com/~apw/lp711568-natty/

Please test and report back here. Thanks.

Revision history for this message

Eric Appleman (erappleman) wrote on 2011-02-08:

#10

Linux kingfisher 2.6.38-3-generic #30~lp711568v201102080908 SMP Tue Feb 8 09:10:43 UTC 2011 i686 i686 i386 GNU/Linux

Patch works. Dithering is back.

Revision history for this message

Andy Whitcroft (apw) wrote on 2011-02-09:

#11

Ok this should be hitting us pretty soon via upstream, it looks like it will be in -rc5 as it is on the intel-fixes branch already. I will pull it in temporarily for futher testing, expecting it to go on on the next rebase.

Changed in linux (Ubuntu):
status:	Triaged → Fix Committed

Bug Watch Updater (bug-watch-updater) on 2011-02-09

Changed in linux:
importance:	Unknown → Medium
status:	Unknown → Fix Released

Revision history for this message

Launchpad Janitor (janitor) wrote on 2011-02-10:

#12

This bug was fixed in the package linux - 2.6.38-3.30

---------------
linux (2.6.38-3.30) natty; urgency=low

[ Andy Whitcroft ]

  * rebase to v2.6.38-rc4
  * ppc64 -- add basic architecture
  * ubuntu: AUFS -- update to 65835da20b77c98fb538c9114fc31f5de1328230

[ Colin Ian King ]

  * SAUCE: Add WMI hotkeys support for Dell All-In-One series
    - LP: #676997
  * SAUCE: Add WMI hotkeys support for another Dell All-In-One series
    - LP: #701530
  * SAUCE: Dell WMI: Use sparse keymaps and tidy up code.
    - LP: #701530

[ Dan Rosenberg ]

* SAUCE: (drop after 2.6.38) Convert net %p usage %pK

[ Kees Cook ]

  * Revert "SAUCE: kernel: make /proc/kallsyms mode 400 to reduce ease of
    attacking"
  * SAUCE: (drop after 2.6.38) use %pK for /proc/kallsyms and /proc/modules

[ Tim Gardner ]

  * [Config] CONFIG_BLK_CGROUP=y
    - LP: #706394
  * [Config] CONFIG_DELL_WMI_AIO=m

[ Upstream Kernel Changes ]

* drm/i915/lvds: Restore dithering on native modes for gen2/3
- LP: #711568

[ Upstream Kernel Changes ]

* rebase from v2.6.38-rc3 to v2.6.38-rc4.
-- Andy Whitcroft <email address hidden> Tue, 08 Feb 2011 02:07:18 +0000