[present + prime] HDMI output (nouveau) broken

[Jean-Louis Dupond]

I recently upgraded my system to Ubuntu 14.10.
Now when testing HDMI, I hit some bug.

My system is an optimus laptop.
The HDMI is connected to a nvidia card.

Now the HDMI has signal, and while logging in (so when Xorg is starting) I can shortly move my cursor over the external display. But when login is complete, the external display is 1 artifact, and doesn't show any updates anymore.

So I started bisecting the version from 14.10 to 14.04 (where it was working).

And I found out the following commit caused the issue:
commit 975b9798be77b30cbed485583d0ccb48318708f7
Author: Chris Wilson <email address hidden>
Date: Wed May 21 08:58:24 2014 +0100

    sna: Add support for Present

    Signed-off-by: Chris Wilson <email address hidden>

Now I recompiled the intel driver without the commit, and that fixes the issue.
Another option is to use --disabled-dri3.

My hardware
00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)
01:00.0 VGA compatible controller: NVIDIA Corporation GF108M [GeForce GT 540M] (rev a1)

The driver I use for the nvidia card is nouveau.

[Jean-Louis Dupond (dupondje)]

I recently upgraded my system to Ubuntu 14.10.
Now when testing HDMI, I hit some bug.

My system is an optimus laptop.
The HDMI is connected to a nvidia card.

Now the HDMI has signal, and while logging in (so when Xorg is starting) I can shortly move my cursor over the external display. But when login is complete, the external display is 1 artifact, and doesn't show any updates anymore.

So I started bisecting the version from 14.10 to 14.04 (where it was working).

And I found out the following commit caused the issue:
commit 975b9798be77b30cbed485583d0ccb48318708f7
Author: Chris Wilson <email address hidden>
Date: Wed May 21 08:58:24 2014 +0100

    sna: Add support for Present

    Signed-off-by: Chris Wilson <email address hidden>

Now I recompiled the intel driver with --disabled-dri3, and that fixes the issue also.

My hardware
00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)
01:00.0 VGA compatible controller: NVIDIA Corporation GF108M [GeForce GT 540M] (rev a1)

The driver I use for the nvidia card is nouveau.

[penalvch (penalvch)]

Jean-Louis Dupond, thank you for taking the time to report this bug and helping to make Ubuntu better. Please execute the following command, as it will automatically gather debugging information, in a terminal:
apport-collect -p xorg 1374618

Please ensure you have the package xdiagnose installed, and that you click the Yes button for attaching additional debugging information.

When reporting bugs in the future please use apport by using 'ubuntu-bug' and the name of the package affected. You can learn more about this functionality at https://wiki.ubuntu.com/ReportingBugs.