Bug#826636: The screensaver fails to hide the second screen in dual screen configuration

[John Paul Adrian Glaubitz]

Control: tags -1 unreproducible
Control: tags -1 moreinfo

Hi Alex!

On 06/07/2016 11:30 AM, Alex Mestiashvili wrote:
> After upgrade from Mate 1.12.0-1 -> 1.14.1-1 the screensaver fails to hide
> the second screen in dual monitor setup.
> One can see the part which suppose to cover the second screen on the first
> primary screen area. It also covers the login dialog, though one still can
> un-lock the session by typing the password.

I am currently sitting in front of a MATE desktop with two displays on Debian
unstable and I cannot reproduce the problem. I just locked the screen and
both screens are properly covered, both with a blank screen as screensaver
as well as "Flying MATE". We therefore need more information to debug this.

Can you make a screenshot? You should be able to do that using a script like:

#!/bin/bash

if [ -d "$1" ]; then
    OUTPUT="$1/xdump_`hostname`.png"
else
    OUTPUT="xdump.png"
fi

if [ -r /var/lib/gdm/:0.Xauth ]; then
    XAUTHORITY=/var/lib/gdm/:0.Xauth DISPLAY=:0.0 xwd -root |xwdtopnm 2>/dev/null |pnmtopng >$OUTPUT
    pngcheck $OUTPUT
elif [ -r /var/lib/gdm3/:0.Xauth ]; then
    XAUTHORITY=/var/lib/gdm3/:0.Xauth DISPLAY=:0.0 xwd -root |xwdtopnm 2>/dev/null |pnmtopng >$OUTPUT
    pngcheck $OUTPUT
elif [ -r /var/lib/mdm/:0.Xauth ]; then
    XAUTHORITY=/var/lib/mdm/:0.Xauth DISPLAY=:0.0 xwd -root |xwdtopnm 2>/dev/null |pnmtopng >$OUTPUT
    pngcheck $OUTPUT
elif [ -r /var/lib/lightdm/.Xauthority ]; then
    XAUTHORITY=/var/lib/lightdm/.Xauthority DISPLAY=:0.0 xwd -root |xwdtopnm 2>/dev/null |pnmtopng >$OUTPUT
    pngcheck $OUTPUT
else
    echo "can't access /var/lib/gdm/:0.Xauth"
    DISPLAY=:0.0 xwd -root |xwdtopnm 2>/dev/null |pnmtopng >$OUTPUT
fi

> Here is the screen setup ( proprietary nvidia driver )

Could you please re-test with the free nouveau driver? This might be related to
the proprietary nVidia driver which cannot properly debug and support anyway
(the sources are with nVidia).

Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer - glaubitz at debian.org
`. `'   Freie Universitaet Berlin - glaubitz at physik.fu-berlin.de
  `-    GPG: 62FF 8A75 84E0 2956 9546  0006 7426 3B37 F5B5 F913