Bug#894098: gdm3: Lockup when connecting externel monitor via DP or HDMI

[Julien Beraud]

Package: gdm3
Version: 3.28.0-1
Severity: important

Dear Maintainer,

With up to date Debian Testing of today March 26th, I have a total lockup of
gnome when connecting my external screen, via HDMI or DP. I have found no other
action than rebooting to regain access to my machine.

The last messages I see when looking at /var/log/messages after a reboot are :
-------------------
Mar 26 09:38:08 julien gnome-shell[1708]: Failed to set CRTC mode 3840x2160:
Argument invalide
Mar 26 09:38:08 julien gnome-shell[1708]: Failed to flip: Argument invalide
Mar 26 09:38:08 julien gnome-shell[1708]: Failed to set CRTC mode 3840x2160:
Argument invalide
Mar 26 09:38:08 julien gnome-session-binary[1697]: Entering running state
Mar 26 09:38:08 julien xbrlapi.desktop[2053]: openConnection: connect: Aucun
fichier ou dossier de ce type
Mar 26 09:38:08 julien xbrlapi.desktop[2053]: cannot connect to braille devices
daemon brltty at :0
Mar 26 09:38:33 julien gsd-xsettings[1959]: Failed to get current display
configuration state: Le délai d’attente est dépassé
Mar 26 09:38:33 julien gnome-session[1697]: gnome-session-binary[1697]:
GnomeDesktop-WARNING: Failed to acquire idle monitor proxy: Le délai d’attente
est dépassé
-------------------------------

This problem appeared today when I was rebooting. I haven't connected my screen
for a week and made some updates in the meantime so it either comes from an
action I did myself or from an update during the course of last week.

Regards,
Julien



-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (500, 'testing'), (150, 'unstable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386, armhf

Kernel: Linux 4.14.0-3-amd64 (SMP w/4 CPU cores)
Locale: LANG=fr_FR.UTF-8, LC_CTYPE=fr_FR.UTF-8 (charmap=UTF-8), LANGUAGE=fr_FR.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages gdm3 depends on:
ii  accountsservice                       0.6.45-1
ii  adduser                               3.117
ii  dconf-cli                             0.26.1-3
ii  dconf-gsettings-backend               0.26.1-3
ii  debconf [debconf-2.0]                 1.5.66
ii  gir1.2-gdm-1.0                        3.28.0-1
ii  gnome-session [x-session-manager]     3.28.0-1
ii  gnome-session-bin                     3.28.0-1
ii  gnome-settings-daemon                 3.28.0-1
ii  gnome-shell                           3.28.0-1
ii  gnome-terminal [x-terminal-emulator]  3.28.0-1
ii  gsettings-desktop-schemas             3.28.0-1
ii  libaccountsservice0                   0.6.45-1
ii  libaudit1                             1:2.8.2-1
ii  libc6                                 2.27-2
ii  libcanberra-gtk3-0                    0.30-6
ii  libcanberra0                          0.30-6
ii  libgdk-pixbuf2.0-0                    2.36.11-2
ii  libgdm1                               3.28.0-1
ii  libglib2.0-0                          2.56.0-2
ii  libglib2.0-bin                        2.56.0-2
ii  libgtk-3-0                            3.22.29-1
ii  libkeyutils1                          1.5.9-9.2
ii  libpam-modules                        1.1.8-3.7
ii  libpam-runtime                        1.1.8-3.7
ii  libpam-systemd                        238-3
ii  libpam0g                              1.1.8-3.7
ii  librsvg2-common                       2.40.20-2
ii  libselinux1                           2.7-2+b1
ii  libsystemd0                           238-3
ii  libwrap0                              7.6.q-27
ii  libx11-6                              2:1.6.5-1
ii  libxau6                               1:1.0.8-1+b2
ii  libxcb1                               1.13-1
ii  libxdmcp6                             1:1.1.2-3
ii  lsb-base                              9.20170808
ii  metacity [x-window-manager]           1:3.28.0-1
ii  mutter [x-window-manager]             3.28.0-2
ii  policykit-1                           0.105-18
ii  ucf                                   3.0038
ii  x11-common                            1:7.7+19
ii  x11-xserver-utils                     7.7+8
ii  xterm [x-terminal-emulator]           331-1

Versions of packages gdm3 recommends:
ii  at-spi2-core    2.28.0-1
ii  desktop-base    9.0.5
ii  x11-xkb-utils   7.7+3+b1
ii  xserver-xephyr  2:1.19.6-1
ii  xserver-xorg    1:7.7+19
ii  zenity          3.28.0-1

Versions of packages gdm3 suggests:
ii  gnome-orca            3.26.0-5
pn  libpam-fprintd        <none>
ii  libpam-gnome-keyring  3.28.0.1-1

-- debconf information:
  gdm3/daemon_name: /usr/sbin/gdm3
* shared/default-x-display-manager: gdm3