Package: gdm3 Version: 3.14.2-2 Severity: important After a recent update, the greeter for gdm3 does not start anymore. Instead the infamous 'Oh no something went wrong" is displayed, with a "Logout" button that cycles back to that same error page.
When I configure automatic login, I get a working session, so gnome-session appears to be working correctly. I did some debugging, and found out that /usr/lib/gnome-session/gnome-session- check-accelerated-helper fails. I ran the program under strace as user Debian- gdm and noticed the following : stat("/dev/nvidiactl", {st_mode=S_IFCHR|0660, st_rdev=makedev(195, 255), ...}) = 0 open("/dev/nvidiactl", O_RDWR) = -1 EACCES (Permission denied) So it looks like that device is not accessible for user Debian-gdm $ ls -l /dev/nvidiactl crw-rw---- 1 root video 195, 255 Sep 27 21:16 /dev/nvidiactl $ groups Debian-gdm Debian-gdm : Debian-gdm Adding the user Debian-gdm to group video fixes the problem. -- System Information: Debian Release: stretch/sid APT prefers unstable APT policy: (500, 'unstable'), (1, 'experimental') Architecture: amd64 (x86_64) Foreign Architectures: i386 Kernel: Linux 4.2.0-1-amd64 (SMP w/8 CPU cores) Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/dash Init: systemd (via /run/systemd/system) Versions of packages gdm3 depends on: ii accountsservice 0.6.40-3 ii adduser 3.113+nmu3 ii dconf-cli 0.24.0-2 ii dconf-gsettings-backend 0.24.0-2 ii debconf [debconf-2.0] 1.5.57 ii gir1.2-gdm3 3.14.2-2 ii gnome-session [x-session-manager] 3.16.0-1 ii gnome-session-bin 3.16.0-1 ii gnome-settings-daemon 3.16.3-1 ii gnome-shell 3.16.3-2 ii gnome-terminal [x-terminal-emulator] 3.18.0-1 ii gsettings-desktop-schemas 3.18.0-1 ii libaccountsservice0 0.6.40-3 ii libaudit1 1:2.4.4-3+b1 ii libc6 2.19-22 ii libcanberra-gtk3-0 0.30-2.1 ii libcanberra0 0.30-2.1 ii libgdk-pixbuf2.0-0 2.32.0-1 ii libgdm1 3.14.2-2 ii libglib2.0-0 2.46.0-1 ii libglib2.0-bin 2.46.0-1 ii libgtk-3-0 3.16.6-1 ii libpam-modules 1.1.8-3.1 ii libpam-runtime 1.1.8-3.1 ii libpam-systemd 226-3 ii libpam0g 1.1.8-3.1 ii librsvg2-common 2.40.10-1 ii libselinux1 2.3-2+b1 ii libsystemd0 226-3 ii libwrap0 7.6.q-25 ii libx11-6 2:1.6.3-1 ii libxau6 1:1.0.8-1 ii libxdmcp6 1:1.1.2-1 ii libxrandr2 2:1.5.0-1 ii lsb-base 9.20150917 ii metacity [x-window-manager] 1:3.17.2-4 ii mutter [x-window-manager] 3.16.3-1 ii policykit-1 0.105-12 ii tinywm [x-window-manager] 1.3-9 ii twm [x-window-manager] 1:1.0.9-1 ii ucf 3.0030 ii x11-common 1:7.7+9 ii x11-xserver-utils 7.7+5 ii xterm [x-terminal-emulator] 320-1 Versions of packages gdm3 recommends: ii at-spi2-core 2.16.0-1 ii desktop-base 8.0.2 ii gnome-icon-theme 3.12.0-1 ii gnome-icon-theme-symbolic 3.12.0-1 ii x11-xkb-utils 7.7+2 ii xserver-xephyr 2:1.17.2-1.1 ii xserver-xorg 1:7.7+9 ii zenity 3.18.0-1 Versions of packages gdm3 suggests: ii gnome-orca 3.16.2-2 ii libpam-gnome-keyring 3.16.0-4 -- debconf information: gdm3/daemon_name: /usr/sbin/gdm3 * shared/default-x-display-manager: gdm3