Bug#860253: xscreensaver: Password dialog is not visible sometimes

[Joshua Honeycutt]

Jamie,

I did some more experimentation using other window environments
(openbox, KDE, Gnome) and I could not reproduce the invisible dialog.
This may just be a caused by the way Xfce handles display changes, but
I don't know enough to come to any conclusion.

Bug#860253: xscreensaver: Password dialog is not visible sometimes

[Jamie Zawinski]

Wow, that's really strange.

--
Jamie Zawinski  https://www.jwz.org/  https://www.dnalounge.com/

Bug#860253: xscreensaver: Password dialog is not visible sometimes

[Joshua Honeycutt]

On Thu, Apr 13, 2017 at 12:03 PM, Jamie Zawinski  wrote:
> Is the screen completely black? Do you have xscreensaver configured to be
> black-only or is it running savers? If you are not running savers, try doing 
> that,
> to see if, when it is in this "invisible" mode, there are any pixels visible 
> at all.

I was configured "Blank Screen Only". The screen was completely black except for
my mouse cursor.

I tried running with a screensaver. Only the dialog area appears black
in this case.
The screensaver freezes while the dialog is active. If I press Esc the
screensaver
continues. Then the dialog appears correctly if activated again by
mouse movement.

This is at least a workaround if I need to see the dialog's state.

It seemed I was able to trigger the blank dialog more easily with a screensaver
enabled (4/4 tries), but only when I suspended and woke via lid
switch. Triggering
the invisible dialog also requires mouse/key activity very quickly
after waking. If I give
time for the screensaver to start running then the dialog displays
normally. I was not
able to reproduce when suspending with a hotkey and waking via power button.

Bug#860253: xscreensaver: Password dialog is not visible sometimes

[Jamie Zawinski]

Is the screen completely black? Do you have xscreensaver configured to be 
black-only or is it running savers? If you are not running savers, try doing 
that, to see if, when it is in this "invisible" mode, there are any pixels 
visible at all.

My guess here is that a bug in your video driver is causing the screen to 
either not be powered on, or is causing the frame buffer to not be displayed. 
That is, the client-facing side of X11 believes there are bits on your screen, 
but the hardware-facing side has lost its mind.

--
Jamie Zawinski  https://www.jwz.org/  https://www.dnalounge.com/

Bug#860253: xscreensaver: Password dialog is not visible sometimes

[Joshua Honeycutt]

Package: xscreensaver
Version: 5.36-1
Severity: important

Dear Maintainer,

Sometimes when xscreensaver is locked and I move the mouse or touch a
key the password dialog does not appear. xscreensaver still responds to
the password being entered and unlocked. The mouse cursor is still
bounded by the area where the dialog would appear, but I only see a
blank black screen (my screensaver is configure to "Blank Screen Only").

I have this issue on two computers, both are running testing
(xscreensaver 5.36-1) and xscreensaver is configured similarly except
for the timer values. Both are running xfce, use intel graphics, one is
a laptop and one is a desktop.

I don't have a good reproduction method. I seemed to be able to
reproduce on the laptop after suspending with the lid close switch. On
the desktop I believe I had the display off or had just turned it on
when I acted for the dialog to appear (the desktop was never in
suspended state).

I have attached a xscreensaver log from the laptop where I did reproduce
the issue on the last lock logged. This lock starts on line 285. Prior
locks had the dialog appear properly.

-- System Information:
Debian Release: 9.0
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.9.0-2-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages xscreensaver depends on:
ii  libatk1.0-0  2.22.0-1
ii  libc62.24-9
ii  libcairo21.14.8-1
ii  libfontconfig1   2.11.0-6.7+b1
ii  libfreetype6 2.6.3-3.1
ii  libgdk-pixbuf2.0-0   2.36.5-2
ii  libglade2-0  1:2.6.4-2
ii  libglib2.0-0 2.50.3-2
ii  libgtk2.0-0  2.24.31-2
ii  libice6  2:1.0.9-2
ii  libpam0g 1.1.8-3.5
ii  libpango-1.0-0   1.40.4-1
ii  libpangocairo-1.0-0  1.40.4-1
ii  libpangoft2-1.0-01.40.4-1
ii  libsm6   2:1.2.2-1+b3
ii  libx11-6 2:1.6.4-3
ii  libxext6 2:1.3.3-1+b2
ii  libxi6   2:1.7.9-1
ii  libxinerama1 2:1.1.3-1+b3
ii  libxml2  2.9.4+dfsg1-2.2
ii  libxmu6  2:1.1.2-2
ii  libxpm4  1:3.5.12-1
ii  libxrandr2   2:1.5.1-1
ii  libxrender1  1:0.9.10-1
ii  libxt6   1:1.1.5-1
ii  libxxf86vm1  1:1.1.4-1+b2
ii  xscreensaver-data5.36-1

Versions of packages xscreensaver recommends:
ii  libgnomeui-0  2.24.5-3.1
pn  libjpeg-turbo-progs   
pn  perl5 
ii  wamerican [wordlist]  7.1-1

Versions of packages xscreensaver suggests:
ii  chromium [www-browser] 57.0.2987.98-1
ii  firefox-esr [www-browser]  45.8.0esr-1
pn  fortune
pn  gdm3 | kdm-gdmcompat   
pn  qcam | streamer
ii  w3m [www-browser]  0.5.3-34
pn  xdaliclock 
pn  xfishtank  
pn  xscreensaver-data-extra
pn  xscreensaver-gl
pn  xscreensaver-gl-extra  

-- no debconf information



##
xscreensaver: 10:12:58: logging to "log.txt" at Thu Apr 13 10:12:58 2017
##

xscreensaver 5.36, copyright (c) 1991-2016 by Jamie Zawinski .
xscreensaver: 10:12:58: running as username/coweater (1000/1000)
xscreensaver: 10:12:58: in process 683.
xscreensaver: 10:12:58: running on display ":0.0"
xscreensaver: 10:12:58: vendor is The X.Org Foundation, 11902000.
xscreensaver: 10:12:58: useful extensions:
xscreensaver: 10:12:58:   MIT Screen-Saver (disabled at compile time)
xscreensaver: 10:12:58:   Shared Memory (1.2)
xscreensaver: 10:12:58:   Double-Buffering (1.0)
xscreensaver: 10:12:58:   Power Management (1.1)
xscreensaver: 10:12:58:   GLX
xscreensaver: 10:12:58:   XF86 Video-Mode (2.2)
xscreensaver: 10:12:58:   XC Misc (disabled at compile time)
xscreensaver: 10:12:58:   Xinerama (1.1)
xscreensaver: 10:12:58:   Resize-and-Rotate (1.5)
xscreensaver: 10:12:58:   XInput
xscreensaver: 10:12:58: screen 0 non-colormapped depths: 24.
xscreensaver: 10:12:58: WARNING: RANDR and Xinerama report different
xscreensaver: 10:12:58: screen layouts!  Believing RANDR.
xscreensaver: 10:12:58: screens in use: 1
xscreensaver: 10:12:58:0/0: 1440x900+0+0 (LVDS1)
xscreensaver: 10:12:58: rejected screens: 4
xscreensaver: 10:12:58:1/0: 1440x900+0+0 (DP1) -- output disabled
xscreensaver: 10:12:58:2/0: 1440x900+0+0 (HDMI1) -- output disabled
xscreensaver: 10:12:58:3/0: 1440x900+0+0 (VGA1) -- output disabled
xscreensaver: 10:12:58:4/0: 0x0+0+0 (VIRTUAL1) -- output disabled
xscreensaver: 10:12:58: selecting RANDR events
xscreensaver: 10:12:58: not using XInputExtension.
xscreensaver: 10:12:58: consulting /proc/interrupts for keyboard activity.
xscreensaver: 10:12:58: 0: visual 0x20 (TrueColor,