kernel-packages team mailing list archive

["Christopher M. Penalver" <christopher.m.penalver@xxxxxxxxx>]

Mark, could you please test the latest upstream kernel available from
the very top line at the top of the page from http://kernel.ubuntu.com
/~kernel-ppa/mainline/?C=N;O=D (the release names are irrelevant for
testing, and please do not test the daily folder)? Install instructions
are available at https://wiki.ubuntu.com/Kernel/MainlineBuilds . This
will allow additional upstream developers to examine the issue.

If the latest kernel did not allow you to test to the issue (ex. you couldn't boot into the OS) please make a comment in your report about this, and continue to test the next most recent kernel version until you can test to the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this issue is fixed in the mainline kernel, please add the following tags by clicking on the yellow circle with a black pencil icon, next to the word Tags, located at the bottom of the report description:
kernel-fixed-upstream
kernel-fixed-upstream-X.Y-rcZ

Where X, and Y are the first two numbers of the kernel version, and Z is
the release candidate number if it exists.

If the mainline kernel does not fix the issue, please add the following tags:
kernel-bug-exists-upstream
kernel-bug-exists-upstream-X.Y-rcZ

Please note, an error to install the kernel does not fit the criteria of
kernel-bug-exists-upstream.

Once testing of the latest upstream kernel is complete, please mark this
report's Status as Confirmed. Please let us know your results.

Thank you for your understanding.

-- 
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https://bugs.launchpad.net/bugs/1486896

Title:
  On Lenovo Thinkpad Edge E330, the screen backlight flickers badly.

Status in linux package in Ubuntu:
  Incomplete

Bug description:
  Behavior is the same on Ubuntu 14.04 -- 15.04.

  Steps were taken according to this:
  https://wiki.ubuntu.com/Kernel/Debugging/Backlight

  With acpi_backlight=vendor, the flicker stops, and the brightness control doesn't work.
  However,
      echo 8 > /sys/class/backlight/intel_backlight/brightness
  dims the screen.

  thinkpad-acpi.brightness_enable = 1 does nothing.

  Old workaround: If no changes are made to boot options, and
      echo 4437 > /sys/class/backlight/intel_backlight/brightness
  is done, the flicker stops and the GUI control / acpi_video0 works, but causes flicker again.

  Workaround 2: Kernel parameters: "thinkpad-acpi.brightness_enable=0
  acpi_backlight=vendor" fully fix the bug behavior and retain the
  brightness control.

  Issue: the intel_backlight device should be used, the workaround above
  disables the other devices, leaving only one, thus no conflicts occur.

  
  Attaching the necessary files.

  ProblemType: Bug
  DistroRelease: Ubuntu 15.04
  Package: linux-image-3.19.0-26-generic 3.19.0-26.28
  ProcVersionSignature: Ubuntu 3.19.0-26.28-generic 3.19.8-ckt4
  Uname: Linux 3.19.0-26-generic x86_64
  ApportVersion: 2.17.2-0ubuntu1.3
  Architecture: amd64
  AudioDevicesInUse:
   USER        PID ACCESS COMMAND
   /dev/snd/controlC0:  mark       1391 F.... pulseaudio
  CurrentDesktop: Unity
  Date: Thu Aug 20 11:21:39 2015
  HibernationDevice: RESUME=UUID=7a9e1f17-c57b-4e6f-bb0c-0b090b5d1405
  InstallationDate: Installed on 2014-08-22 (363 days ago)
  InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
  MachineType: LENOVO 3354DGG
  ProcFB: 0 inteldrmfb
  ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.19.0-26-generic root=UUID=b566feb2-5a5c-4573-8782-b78d130dbc45 ro quiet splash acpi_backlight=vendor vt.handoff=7
  RelatedPackageVersions:
   linux-restricted-modules-3.19.0-26-generic N/A
   linux-backports-modules-3.19.0-26-generic  N/A
   linux-firmware                             1.143.3
  SourcePackage: linux
  UpgradeStatus: Upgraded to vivid on 2015-08-20 (0 days ago)
  dmi.bios.date: 02/25/2013
  dmi.bios.vendor: LENOVO
  dmi.bios.version: H3ET72WW(1.09)
  dmi.board.asset.tag: Not Available
  dmi.board.name: 3354DGG
  dmi.board.vendor: LENOVO
  dmi.board.version: 0B98409 Std
  dmi.chassis.asset.tag: No Asset Information
  dmi.chassis.type: 10
  dmi.chassis.vendor: LENOVO
  dmi.chassis.version: Not Available
  dmi.modalias: dmi:bvnLENOVO:bvrH3ET72WW(1.09):bd02/25/2013:svnLENOVO:pn3354DGG:pvrThinkPadEdgeE330:rvnLENOVO:rn3354DGG:rvr0B98409Std:cvnLENOVO:ct10:cvrNotAvailable:
  dmi.product.name: 3354DGG
  dmi.product.version: ThinkPad Edge E330
  dmi.sys.vendor: LENOVO

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