Dear Maintainer,

I'm having issues in Debian Jessie similar to those described in
700235 where between entering my password in
lightdm and the MATE desktop environment appearing I get:
* on a clean boot a green screen with random coloured speckles
* on subsequent reboots a collage of bits of the screen from previous boots.

Sometimes the bits of the screen can be from 2 or 3 clean boots ago, even
sometimes showing
bits of webpages visited the previous day.  My PC's been off at the wall
overnight.

This differs from 700235 in that it looks from the last comment like,
for that person, it's been resolved in the version I'm running.
------------------

The following workarounds from similar bugs have not helped:

NOT HELPING (suggested workaround from 732854): /etc/X11/xorg.conf:
Section "Extensions"
        Option "Composite" "0"
EndSection


This doesn't work either (from 700235):
echo "LIBGL_ALWAYS_SOFTWARE=1" >> /etc/environment

I also tried, before attempting either of the above workarounds, enabling
compositing in MATE itself and it didn't fix the issue, nor has disabling
it again.

----------------------------

Driver version info:

Package: xserver-xorg-video-nouveau
Version: 1:1.0.11-1

Some more debugging...

I've been able to remove this problem by adding the nomodeset option to
the Linux command line, in that there is no display corruption during
login with nomodeset, and the previous display contents aren't revealed
until I next boot without the nomodeset option.

It's not a good solution, because  I'm left with a poor X display
resolution and a lower-resolution console; and the desktop is still
shown right to the point the machine is powered off at the end of shutdown.

Note I also reported bug #783881 which I found on the same machine as
this one.  I mention that because I think there's an outside chance
these bugs could be related.  The nomodeset option also appears after
minimal number of tests to work around the shutdown issues described
there, just as well as redirecting the console to serial port.

Dear Maintainers,

Similar symptoms can be observed in my system. Previous screen contents is visible:
1. between XDM login and desktop display,
2. during regular work: "I see dead windows" (or screens), closed like 5 days earlier,
popping out over the current contents. Running Iceweasel, Gimp and Libre Office seem
to increase the probability of screen corruption, but I've not found any reliable
steps to reproduce.

I was fine using unstable version of nouveau till the beginning of may.

Best regards

Dear Maintainers!

Two recent observations:

1. It's funny, but I can actually capture the corrupted screen with XFCE "Screen Capture"
widget.

2. Option "Composite" "0"  does not help

Best regards

Hi again,

I can pinpoint now my problem to a tandem of xserver-xorg-video-nouveau
(either in current stable and testing/unstable) and xfwm4 in version 4.12.

More specifically XFWM in recent version (4.12):
1. triggers problem when used with nouveau 1.0.11 [b1] and G92.
2. works OK with nouveau 1.0.11 and G86
3. works OK with Intel graphics.

There are several points in XFWM changelog that looks suspicious (like
https://bugzilla.xfce.org/show_bug.cgi?id=8898 applied in 4.12), but no
clue what to investigate further.

Best regards