[i915gm] screen repeatedly goes black for a fraction of a second (two monitors detected?)

[Cobalt]

Binary package hint: xorg

Since I upgraded from Ubuntu 10.04 to 10.10, the monitor displays correctly for a couple of seconds, then turns black for a fraction of a second and then repeats the on and off sequence, making the computer nearly unusable.

The whole sequence is periodic, not random.

Another bug reported earlier (#606987) persists in this release as well, perhaps with the exception that restarting the computer (as opposed to turning it on after a shutdown) gives a normal logon screen. (I only used Restart a couple of times since the upgrade.)

Thanks and regards

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: xorg 1:7.5+6ubuntu3
ProcVersionSignature: Ubuntu 2.6.35-23.40-generic 2.6.35.7
Uname: Linux 2.6.35-23-generic i686
Architecture: i386
DRM.card0.DVI.D.1:
 status: connected
 enabled: enabled
 dpms: On
 modes: 1680x1050 1600x1000 1280x1024 1280x1024 1440x900 1440x900 1152x864 1024x768 1024x768 1024x768 800x600 800x600 800x600 640x480 640x480 640x480 640x480 720x400
 edid-base64: AP///////wAwrkYRAQEBATESAQOAMB547u6Vo1RMmSYPUFStzwAxRnFPgYCVAJUPqQCzAAEBfC6QoGAaHkAwIDYA2SgRAAAaAAAA/ABMMjI0MHB3RAogICAgAAAA/QAySx5LDwAKICAgICAgAAAA/wA2VjYwMTg3MQogICAgAJ4=
DRM.card0.VGA.1:
 status: connected
 enabled: enabled
 dpms: On
 modes: 1680x1050 1600x1000 1280x1024 1280x1024 1440x900 1440x900 1152x864 1024x768 1024x768 1024x768 800x600 800x600 800x600 640x480 640x480 640x480 640x480 720x400
 edid-base64: AP///////wAwrkYRAQEBATESAQOAMB547u6Vo1RMmSYPUFStzwAxRnFPgYCVAJUPqQCzAAEBfC6QoGAaHkAwIDYA2SgRAAAaAAAA/ABMMjI0MHB3RAogICAgAAAA/QAySx5LDwAKICAgICAgAAAA/wA2VjYwMTg3MQogICAgAJ4=
Date: Wed Nov 24 18:09:03 2010
MachineType: ASUSTeK Computer INC. NOVALITE PX20
ProcCmdLine: root=UUID=37b5536f-4bc2-458a-8381-a46d761e21ac ro quiet splash
ProcEnviron:
 LANG=en_US.utf8
 SHELL=/bin/bash
SourcePackage: xorg
Symptom: display
dmi.bios.date: 01/25/2008
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 0501
dmi.board.asset.tag: To Be Filled By O.E.M.
dmi.board.name: PXP5M1-DHS
dmi.board.vendor: ASUSTeK Computer INC.
dmi.board.version: 0501
dmi.chassis.asset.tag: 0x00000000
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTek Computer INC.
dmi.chassis.version: x.x
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr0501:bd01/25/2008:svnASUSTeKComputerINC.:pnNOVALITEPX20:pvr0501:rvnASUSTeKComputerINC.:rnPXP5M1-DHS:rvr0501:cvnASUSTekComputerINC.:ct10:cvrx.x:
dmi.product.name: NOVALITE PX20
dmi.product.version: 0501
dmi.sys.vendor: ASUSTeK Computer INC.
system:
 distro: Ubuntu
 codename: maverick
 architecture: i686
 kernel: 2.6.35-23-generic
---
Architecture: i386
CurrentDmesg: [ 34.032023] eth0: no IPv6 routers present
DRM.card0.DVI.D.1:
 status: connected
 enabled: enabled
 dpms: Off
 modes: 1680x1050 1600x1000 1280x1024 1280x1024 1440x900 1440x900 1152x864 1024x768 1024x768 1024x768 800x600 800x600 800x600 640x480 640x480 640x480 640x480 720x400
 edid-base64: AP///////wAwrkYRAQEBATESAQOAMB547u6Vo1RMmSYPUFStzwAxRnFPgYCVAJUPqQCzAAEBfC6QoGAaHkAwIDYA2SgRAAAaAAAA/ABMMjI0MHB3RAogICAgAAAA/QAySx5LDwAKICAgICAgAAAA/wA2VjYwMTg3MQogICAgAJ4=
DRM.card0.VGA.1:
 status: connected
 enabled: enabled
 dpms: Off
 modes: 1680x1050 1600x1000 1280x1024 1280x1024 1440x900 1440x900 1152x864 1024x768 1024x768 1024x768 800x600 800x600 800x600 640x480 640x480 640x480 640x480 720x400
 edid-base64: AP///////wAwrkYRAQEBATESAQOAMB547u6Vo1RMmSYPUFStzwAxRnFPgYCVAJUPqQCzAAEBfC6QoGAaHkAwIDYA2SgRAAAaAAAA/ABMMjI0MHB3RAogICAgAAAA/QAySx5LDwAKICAgICAgAAAA/wA2VjYwMTg3MQogICAgAJ4=
DistroRelease: Ubuntu 10.10
DkmsStatus: Error: [Errno 2] No such file or directory
MachineType: ASUSTeK Computer INC. NOVALITE PX20
Package: xserver-xorg-video-intel 2:2.14.0+git20110122.5baa63c6-0ubuntu0sarvatt~maverick
PackageArchitecture: i386
ProcCmdLine: root=UUID=37b5536f-4bc2-458a-8381-a46d761e21ac ro quiet splash
ProcEnviron:
 LANG=en_US.utf8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.35-25.44-generic 2.6.35.10
Tags: maverick maverick
Uname: Linux 2.6.35-25-generic i686
UnreportableReason: This is not a genuine Ubuntu package
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare
dmi.bios.date: 01/25/2008
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 0501
dmi.board.asset.tag: To Be Filled By O.E.M.
dmi.board.name: PXP5M1-DHS
dmi.board.vendor: ASUSTeK Computer INC.
dmi.board.version: 0501
dmi.chassis.asset.tag: 0x00000000
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTek Computer INC.
dmi.chassis.version: x.x
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr0501:bd01/25/2008:svnASUSTeKComputerINC.:pnNOVALITEPX20:pvr0501:rvnASUSTeKComputerINC.:rnPXP5M1-DHS:rvr0501:cvnASUSTekComputerINC.:ct10:cvrx.x:
dmi.product.name: NOVALITE PX20
dmi.product.version: 0501
dmi.sys.vendor: ASUSTeK Computer INC.
system:
 distro: Ubuntu
 codename: maverick
 architecture: i686
 kernel: 2.6.35-25-generic

---
Architecture: i386
DRM.card0.DVI.D.1:
 status: connected
 enabled: enabled
 dpms: Off
 modes: 1680x1050 1600x1000 1280x1024 1280x1024 1440x900 1440x900 1152x864 1024x768 1024x768 1024x768 800x600 800x600 800x600 640x480 640x480 640x480 640x480 720x400
 edid-base64: AP///////wAwrkYRAQEBATESAQOAMB547u6Vo1RMmSYPUFStzwAxRnFPgYCVAJUPqQCzAAEBfC6QoGAaHkAwIDYA2SgRAAAaAAAA/ABMMjI0MHB3RAogICAgAAAA/QAySx5LDwAKICAgICAgAAAA/wA2VjYwMTg3MQogICAgAJ4=
DRM.card0.VGA.1:
 status: connected
 enabled: disabled
 dpms: Off
 modes:
 edid-base64:
DistroRelease: Ubuntu 10.10
DkmsStatus: Error: [Errno 2] No such file or directory
MachineType: ASUSTeK Computer INC. NOVALITE PX20
Package: xserver-xorg-video-intel 2:2.14.0+git20110214.23f9b14d-0ubuntu0sarvatt~maverick
PackageArchitecture: i386
ProcCmdLine: root=UUID=37b5536f-4bc2-458a-8381-a46d761e21ac ro quiet splash video=VGA-1:d
ProcEnviron:
 LANG=en_US.utf8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.35-25.44-generic 2.6.35.10
Tags: maverick maverick
Uname: Linux 2.6.35-25-generic i686
UnreportableReason: This is not a genuine Ubuntu package
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare
dmi.bios.date: 01/25/2008
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 0501
dmi.board.asset.tag: To Be Filled By O.E.M.
dmi.board.name: PXP5M1-DHS
dmi.board.vendor: ASUSTeK Computer INC.
dmi.board.version: 0501
dmi.chassis.asset.tag: 0x00000000
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTek Computer INC.
dmi.chassis.version: x.x
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr0501:bd01/25/2008:svnASUSTeKComputerINC.:pnNOVALITEPX20:pvr0501:rvnASUSTeKComputerINC.:rnPXP5M1-DHS:rvr0501:cvnASUSTekComputerINC.:ct10:cvrx.x:
dmi.product.name: NOVALITE PX20
dmi.product.version: 0501
dmi.sys.vendor: ASUSTeK Computer INC.
system:
 distro: Ubuntu
 codename: maverick
 architecture: i686
 kernel: 2.6.35-25-generic
---
Architecture: i386
DRM.card0.HDMI.A.1:
 status: connected
 enabled: enabled
 dpms: On
 modes: 1680x1050 1600x1000 1280x1024 1280x1024 1440x900 1440x900 1152x864 1024x768 1024x768 1024x768 800x600 800x600 800x600 640x480 640x480 640x480 640x480 720x400
 edid-base64: AP///////wAwrkYRAQEBATESAQOAMB547u6Vo1RMmSYPUFStzwAxRnFPgYCVAJUPqQCzAAEBfC6QoGAaHkAwIDYA2SgRAAAaAAAA/ABMMjI0MHB3RAogICAgAAAA/QAySx5LDwAKICAgICAgAAAA/wA2VjYwMTg3MQogICAgAJ4=
DRM.card0.VGA.1:
 status: disconnected
 enabled: disabled
 dpms: Off
 modes:
 edid-base64:
DistUpgraded: Fresh install
DistroCodename: natty
DistroRelease: Ubuntu 11.04
DistroVariant: ubuntu
GdmLog1: Not present
GdmLog2: Not present
GraphicsCard:
 Subsystem: ASUSTeK Computer Inc. Device [1043:82d9]
   Subsystem: ASUSTeK Computer Inc. Device [1043:82d9]
LiveMediaBuild: Ubuntu 11.04 "Natty Narwhal" - Alpha i386 (20110214)
MachineType: ASUSTeK Computer INC. NOVALITE PX20
Package: xserver-xorg-video-intel 2:2.14.0-1ubuntu7
PackageArchitecture: i386
ProcEnviron:
 LANGUAGE=en_US.UTF-8:en
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: file=/cdrom/preseed/hostname.seed boot=casper initrd=/casper/initrd.lz quiet splash -- maybe-ubiquity
ProcVersionSignature: Ubuntu 2.6.38-3.30-generic 2.6.38-rc4
Tags: natty running-unity ubuntu
Uname: Linux 2.6.38-3-generic i686
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare
dmi.bios.date: 01/25/2008
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 0501
dmi.board.asset.tag: To Be Filled By O.E.M.
dmi.board.name: PXP5M1-DHS
dmi.board.vendor: ASUSTeK Computer INC.
dmi.board.version: 0501
dmi.chassis.asset.tag: 0x00000000
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTek Computer INC.
dmi.chassis.version: x.x
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr0501:bd01/25/2008:svnASUSTeKComputerINC.:pnNOVALITEPX20:pvr0501:rvnASUSTeKComputerINC.:rnPXP5M1-DHS:rvr0501:cvnASUSTekComputerINC.:ct10:cvrx.x:
dmi.product.name: NOVALITE PX20
dmi.product.version: 0501
dmi.sys.vendor: ASUSTeK Computer INC.
version.compiz: compiz 1:0.9.2.1+glibmainloop4-0ubuntu11
version.libdrm2: libdrm2 2.4.23-1ubuntu3
version.libgl1-mesa-glx: libgl1-mesa-glx 7.10-1ubuntu1
version.xserver-xorg: xserver-xorg 1:7.6~3ubuntu4
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.13.2+git20110124.fadee040-0ubuntu4
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.14.0-1ubuntu7
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20110107+b795ca6e-0ubuntu4
---
Architecture: i386
DistroRelease: Ubuntu 11.04
LiveMediaBuild: Ubuntu 11.04 "Natty Narwhal" - Beta i386 (20110405)
Package: xserver-xorg-video-intel 2:2.14.0-4ubuntu6
PackageArchitecture: i386
ProcEnviron:
 LANGUAGE=en_US:en
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.38-7.39-generic 2.6.38
Tags: natty running-unity
Uname: Linux 2.6.38-7-generic i686
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare

[lspci]
Nux: lspci: 00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile 915GM/GMS/910GML Express Graphics Controller [8086:2592] (r

[Cobalt (cliapis)]

Natty (from USB stick) gives no improvement.

[Bryce Harrington (bryce)]

I notice there is a typo in your xorg.conf:

        Option "metamodes" "CRT-0: 1680x1050

You're missing quotes.

Also, you should include an explanation in your bug report why you're using an xorg.conf, since for this hardware you typically shouldn't need to use an xorg.conf except in specific circumstances.

Do a 'tail -f /var/log/Xorg.0.log' and check if the file grows each time the screen blanks.

[Cobalt (cliapis)]

Regarding xorg.conf on my hard disk, which has Ubuntu 10.10 - I renamed it so as to have no file with exactly that name, but the problem persists in 10.10, as it does with a live CD for natty.

Regarding Xorg.0.log - no, it does not grow as the screen goes blank.

[Bryce Harrington (bryce)]

Hmm, ok reason I ask is looking at your Xorg.0.log everything looks totally bog standard except at the end there are 9 sequences of XRANDR queries to the monitor. Those queries can typically cause screen flickers such as what you're seeing. And it is not unprecedented for some arbitrary client application to set up polling calls of X server such as to check if a new monitor is installed; on some hardware this works without flicker, on some it does. This behavior is typically highly periodic, such as you're seeing. A way to check if this is the case would be to review what processes you have running (e.g. look at ps aux) and one by one shut them down until the blanking stops.

The other typical cause of blanking issues like this is underruns of the GPU. Basically, X is not able to feed data through to your graphics card fast enough. Often when this happens, there are error messages printed to dmesg and/or Xorg.0.log, yet this does not appear in your logs. Also, this problem tends to be intermittent/random rather than periodic.

[Bryce Harrington (bryce)]

If you do rule out a client app, or otherwise want to continue exploring it as an X issue specifically, here's the next step.

We're going to be moving natty to its new X stack within the next week or two. Currently this stack is available in xorg-edgers, and should match almost exactly what will soon be in natty.

I'd like to have you attempt to reproduce your issue with this new stack. If it still occurs with that stack, we can then take the the bug upstream, or approach the kernel team or other appropriate groups about it.

The PPA is available at: https://launchpad.net/~xorg-edgers/+archive/ppa

Here's a simple way to install:
  sudo add-apt-repository ppa:xorg-edgers/ppa
  sudo apt-get update
  sudo apt-get upgrade

Then reboot your system to get to the new bits.

If you want to go back to stock Ubuntu, there is a corresponding ppa-purge tool:
  sudo ppa-purge xorg-edgers
  sudo apt-get update
  sudo apt-get upgrade

[Cobalt (cliapis)]

a) With a live CD for natty, the display is fine up to the screen where I am shown the menu that includes using Ubuntu without installing. Once I choose this option the display changes and the name ubuntu appears, underscored by five dots whose color changes from white to red and back to show that the computer is doing work. It is there that the screen starts to blink.

b) For maverick, the PPA gives no improvement. Since there are dozens of processes even at startup, many run by root, I am not sure which ones to kill short of taking down gnome. Could you perhaps suggest candidates?

[Chris Halse Rogers (raof)]

It seems that you've got two monitors plugged in - does this problem occur on both monitors simultaneously, both monitors independently, or just one monitor?

Does this still happen if you unplug one of the monitors? (I'd start with the VGA monitor, as I think it's more likely to have problems)

If you *don't* have two monitors plugged in (and the EDID information is suspicious, unless you've got two identical monitors plugged in), then there's at least one problem diagnosed ☺.

[Cobalt (cliapis)]

No, I have only one monitor, although at some level - at least for maverick and older versions - the computer seems to think that I have two. This is probably at least part of the cause of the other bug (#606987) I mentioned in the original description of this problem.

Again, maverick runs from the hard drive; natty only from a live CD.

[Bryce Harrington (bryce)]

[Bumping priority to high since it's a regression, although at this time we know of only one affected machine]

[Bryce Harrington (bryce)]

Could you run the command 'apport-collect 681054' while running the xorg-edgers bits? That will attach files with the proper versions, which will allow us to forward this bug report upstream. Since it affects xorg-edgers too, it's likely to be a bug in the upstream code, and they may have more of a clue what's going wrong.

[Chris Halse Rogers (raof)]

Another useful thing to try would be to see if disabling the phantom output makes things better.

To do that you would need to access the grub menu and add “video=VGA1:d” (if your monitor is not connected via a VGA cable) to the end of the kernel command line.

[Cobalt (cliapis)]

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[Cobalt (cliapis)]

Reran apport following Bryce's #11 and will try #12 during the weekend.

[Cobalt (cliapis)]

Adding video=VGA-1:d at the end of the kernel line in GRUB

[Cobalt (cliapis)]

Adding video=VGA-1:d at the end of the kernel line in GRUB menu.lst (hint from Chris in #12) corrects the problem in earlier bug (#606987) but does not change the screen's blinking.

[Bryce Harrington (bryce)]

Hmm, this should probably be forwarded upstream as the next step. Betting that both the blinking and the phantom output are related.

[Bryce Harrington (bryce)]

Hi Cobalt, are you still reproducing this bug on latest natty? If so, like I mentioned I think the next step is to forward it upstream. Now that natty has been updated to the latest kernel and X bits, we can do this. Can you again run apport-collect 681054 to put the new logs onto the bug report? If you can do this after the system starts exhibiting the bug, that would be helpful.

Also, did you sort out a way to work around the issue?

[Cobalt (cliapis)]

a) Booted from natty live CD dated Feb. 14. The screen still blinks.

b) For maverick, no workaround for this bug, only for #606987 as mentioned in #38. Rerunning apport-collect 681054.

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[Bryce Harrington (bryce)]

No Cobalt, those are maverick logs again, you need to have natty logs from running apport on natty. Otherwise upstream won't look at the bug report since the versions are too old.

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[Cobalt (cliapis)]

Sorry, Bryce, I misunderstood what you wanted me to do. I am running natty from a live CD and have just run apport to update this report. Hope that helps.

[Bryce Harrington (bryce)]

Hi Cobalt, just to check - are you still experiencing this bug?

[Cobalt (cliapis)]

Hi, Bryce! Yes, I am still experiencing this bug. (Otherwise I would have cancelled the report.) I have been updating my maverick with xorg-edgers and the bug has not gone away. I have also tried natty from a live CD, last time was at the time of note #84.

I would also like to remind you that this is a regression (see also your note #10).

[Bryce Harrington (bryce)]

Thanks; re-testing xorg-edgers is helpful but this is almost certainly a kernel bug. xorg-edgers doesn't carry kernel updates, so I wouldn't expect it'd solve this. Instead, download and boot a new daily cd, then run 'apport-collect 681054' to update the logs.

This is kind of a borderline High/Medium importance... on the one hand it is a severe issue, on the other it appears to affect only a single person. I'll bump it back to high for now.

[Cobalt (cliapis)]

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[Cobalt (cliapis)]

Thanks a lot for your message and explanation, Bryce. I have used a natty live CD from April 5 and attached the apport info again.

[Bryce Harrington (bryce)]

Can you confirm that you are still seeing this problem with the natty release?

If you are, can you test one more thing please - we are now providing builds of upstream's experimental driver and I'd like to confirm it also affects their code as well before we send this bug upstream. Please install the kernel and reboot onto it, reproduce the bug, and then attach a fresh 'dmesg > dmesg.txt' here. Thanks ahead of time!

[Cobalt (cliapis)]

Hi, Bryce,

could we coordinate further processing with upstream? I understand everybody has a lot of work to do, so I would like to know you are ready to forward the report and upstream is ready to look into it if I test again. I have tested edgers and especially natty several times only to be asked to test again weeks later since the upstream code might have changed in the mean time.

Is there any reason to think that this particular issue may have been addressed, however? Actually, I would expect upstream to be able to answer this question quickly and if they want me to retest I will be happy to do it.

Regarding the kernel, well, I have used live CD's for natty. Do you want me to retest maverick with a new kernel? If so, where do I get the experimental version?

Thanks a lot.

[Bryce Harrington (bryce)]

[I've marked this bug for inclusion in our oneiric bug queue. While technically this bug has not been re-confirmed against oneiric, I feel it is worth continued development attention. We will need to ask that it be re-confirmed once oneiric is further along, perhaps once we get closer to alpha.]

[Bryce Harrington (bryce)]

Forwarding this bug from Ubuntu reporter Cobalt:
https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/681054

[Problem]
Very brief periodic screen blanking every couple seconds. Regression began in 10.10 and continues in 11.04. Reporter has been testing upstream git snapshots and finds problem still persists.

[Original Description]
Since I upgraded from Ubuntu 10.04 to 10.10, the monitor displays correctly for a couple of seconds, then turns black for a fraction of a second and then repeats the on and off sequence, making the computer nearly unusable.

The whole sequence is periodic, not random.

Another bug reported earlier (#606987) persists in this release as well, perhaps with the exception that restarting the computer (as opposed to turning it on after a shutdown) gives a normal logon screen. (I only used Restart a couple of times since the upgrade.)

With a live CD for natty, the display is fine up to the screen where I am shown the menu that includes using Ubuntu without installing. Once I choose this option the display changes and the name ubuntu appears, underscored by five dots whose color changes from white to red and back to show that the computer is doing work. It is there that the screen starts to blink.

I have only one monitor, although at some level - at least for maverick and older versions - the computer seems to think that I have two. This is probably at least part of the cause of the other bug (#606987) I mentioned in the original description of this problem.

Thanks and regards

DistUpgraded: Fresh install
GraphicsCard:
 Subsystem: ASUSTeK Computer Inc. Device [1043:82d9]
   Subsystem: ASUSTeK Computer Inc. Device [1043:82d9]
MachineType: ASUSTeK Computer INC. NOVALITE PX20
version.compiz: compiz 1:0.9.2.1+glibmainloop4-0ubuntu11
version.libdrm2: libdrm2 2.4.23-1ubuntu3
version.libgl1-mesa-glx: libgl1-mesa-glx 7.10-1ubuntu1
version.xserver-xorg: xserver-xorg 1:7.6~3ubuntu4
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.13.2+git20110124.fadee040-0ubuntu4
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.14.0-1ubuntu7
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20110107+b795ca6e-0ubuntu4
Architecture: i386
DistroRelease: Ubuntu 11.04
LiveMediaBuild: Ubuntu 11.04 "Natty Narwhal" - Beta i386 (20110405)
Package: xserver-xorg-video-intel 2:2.14.0-4ubuntu6
PackageArchitecture: i386
Uname: Linux 2.6.38-7-generic i686

[lspci]
Nux: lspci: 00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile 915GM/GMS/910GML Express Graphics Controller [8086:2592] (r

[Bryce Harrington (bryce)]

Created attachment 47083
BootDmesg.txt

[Bryce Harrington (bryce)]

Created attachment 47084
CurrentDmesg.txt

[Bryce Harrington (bryce)]

Created attachment 47085
XorgLog.txt

[Bryce Harrington (bryce)]

Cobalt - I've forwarded this bug upstream to http://bugs.freedesktop.org/show_bug.cgi?id=37526 - please subscribe yourself to this bug, in case they need further information or wish you to test something. Thanks ahead of time!

[Chris Wilson (ickle)]

There are too many possible factors; from output polling to fbc and fifos. Can we identify when the regression was introduced?

[Chris Wilson (ickle)]

The workaround will be echo 0 > /sys/module/drm_kms_helper/parameters/poll. But that won't tell us why the periodic polling is causing the output to blank... Load detection on the VGA should be possible with the current mode settings, and the VGA crtc should not be stolen for any other load detections (TV).

[Chris Wilson (ickle)]

The workaround would be to disable polling (drm_kms_helper.poll=0). Improving the locking around modesetting is a longer term issue, but I think the fundamental issue is more likely to a FIFO starvation when doing load-detection on the second pipe. Which falls into the DSPARB terroritory. A full drm.debug=0xe dmesg for boot-up + blanking period would help.

(Reducing priority, not going to be fixed in the immediate term.)

[Bryce Harrington (bryce)]

Hi Cobalt, upstream has several questions.

 * Can you help pinpoint when exactly the regression first started?

 * Does this workaround make it stop?
    echo 0 > /sys/module/drm_kms_helper/parameters/poll

Please install xdiagnose, run 'sudo xdiagnose' and turn on debug messages (the first checkbox). Then reboot, and do whatever you need to do to reproduce the blanking bug. Then, run 'sudo dmesg > dmesg.txt' and attach the dmesg.txt to the upstream bug report at https://bugs.freedesktop.org/show_bug.cgi?id=37526

[Cobalt (cliapis)]

Hi, Bryce, I appreciate your explanation. I am not proficient enough to understand Chris' rather technical note.

I am not sure about the checkbox you mentioned though. I typed sudo xdiagnose and then the system showed a bunch of lines, which I copied into the traceback.txt file (attached). I am also attaching the dmesg output. Could you take a look and let me know if this is good enough?

The workaround you mentioned works for me. It stops the blinking.

Thanks a lot.

[Chris Halse Rogers (raof)]

The debugging information Chris Wilson is after can be gathered by adding ‘drm.debug=0xe’ to your kernel command line - you can do that the same way that you added “video=VGA-1:d”. Once you've booted, and the screen has flickered a bit, please grab dmesg and attach it here.

You should also be able to add “drm_kms_helper.poll=0” to your kernel command line in /etc/default/grub if you want that work around to be permanently enabled.

[Cobalt (cliapis)]

Attaching dmesg.txt after upgrading to oneiric.

[Bryce Harrington (bryce)]

Created attachment 56587
dmesg.txt

[Bryce Harrington (bryce)]

drm_kms_helper.poll=0 did indeed prove to help the user.
We're still waiting on the dmesg data from him.

[Bryce Harrington (bryce)]

Hi Cobalt, could you try attaching the dmesg.txt again? It appears to have not gotten saved in launchpad for some reason.

Or, go ahead and post it directly to the bug at https://bugs.freedesktop.org/show_bug.cgi?id=37526

[Jesse Barnes (jbarnes-virtuousgeek)]

Some of the recent i2c improvements may have helped too, worth verifying.

[Daniel-ffwll (daniel-ffwll)]

To be slightly more precise, please test the drm-intel-next-queued branch from my git repository at http://cgit.freedesktop.org/~danvet/drm/

[Bryce Harrington (bryce)]

Cobalt, upstream believes they have found the fix for this bug. It is included in their upstream git branch. Debs for you to install and test are provided here:

  http://kernel.ubuntu.com/~kernel-ppa/mainline/drm-intel-experimental/

Please install and test this ASAP and let us know if it fixes the issue for you.

[Cobalt (cliapis)]

Hi, Bryce, sorry about the late response. My monitor died and it took me a while to get a replacement - same model. I am attaching the dmesg output and will try to install the fix soon.

When I replaced the monitor I realized - and wish I had done it sooner - that the monitor does not flicker when connected to the computer via the analog cable (with the help of an adapter).

[Cobalt (cliapis)]

Launchpad seems to have lost the attachment. Trying again.

[Cobalt (cliapis)]

Hi, Bryce, sorry about the delay. I had to be away from home.

I take it I need to upgrade to 12.04. Do I need to install both the linux-header and linux-image debs? What about the difference between the pae debs and the rest? Which ones do I need to install?

Thanks very much.

[Daniel-ffwll (daniel-ffwll)]

Upstream reporter seems to have gone awol, closing because if missing data. Please reopen only when the request dmesg is available (and preferably the bisect result).

[Bryce Harrington (bryce)]

Cobalt, feel free to reopen if you can complete the directions provided for collecting the necessary information.

If you have questions on how to perform the technical steps, use http://askubuntu.com for technical support.