Just a quick note because I think I have a lead, but won't be able to go through all your suggestions today.
First of all, I'm also unable to reproduce the issue if I go straight to logging into the Gnome session after booting my VM. However I am able to reproduce it if I first log into and log out of a few other session types. I'm still trying to figure out the minimal set which triggers the issue consistently, but so far I can see the issue if I: - boot the VM - log into LXDE session and log out - log into Cinnamon session and log out - log into "System X11 default" session which I think is LXQT in this case, and log out - log into Gnome session - lock the screen through the menu in upper right-hand corner - try to unlock FWIW, the message which "journalctl -f" shows (in an ssh session running in parallel) when I enter the unlock password is: lut 28 21:48:52 debian gdm-password][38277]: gkr-pam: unlocked login keyring A few replies to some of your points below, I'll keep digging whenever I have some free time in the coming week. sob., 27 lut 2021 o 22:28 Simon McVittie <s...@debian.org> napisaĆ(a): > On Sat, 27 Feb 2021 at 19:21:46 +0100, Marcin Owsiany wrote: > > Regarding the messages I see in syslog, see the screenshot I had > attached to my > > previous message. > > On a freshly-installed, up to date test VM, you should find that the gdm > login screen has a grey background, but the gnome-shell lock screen has a > dark blue background (it's a blurred version of your desktop background, > for which the default in Debian 11 is going to be dark blue). Right, I'm pretty sure the weird behaviour is in the lock screen, not the gdm login screen. > It would > be useful if you could describe the steps you use to reproduce this bug, > and at each step that involves a login screen, say whether the background > is grey or blue. > > Here is a sequence of screenshots illustrating my > attempt to reproduce this, together with my system log: > <https://people.debian.org/~smcv/973474/> (and then after pressing Enter > for my test user's password, I'm back to my unlocked session, equivalent > to <https://people.debian.org/~smcv/973474/5.png>). At what point does > what you see diverge from that? > > I'm surprised you see messages from Xorg: those should only appear when > you start a completely new session, not when you just lock and unlock > the screen. This suggests that maybe the session is crashing, and instead > of the gnome-shell lock screen on tty7, you are going back to the gdm > login screen on tty1. > As far as I can tell it's not crashing. Could they have been triggered by switching between virtual consoles? Going forward I'll try to use a parallel SSH login rather than messing around with CTRL+ALT+Fx to keep things simpler. > Given that you see messages from Xorg, I would also expect to see more > messages than just those. Before locking the screen, please run > > logger "before locking" > > to leave a marker in the system log; and then please look back through > the system log at least as far as that marker. > > If you look at the systemd journal (as root) instead of syslog, you'll > also see "auth" messages, which could be relevant: for instance, when > you enter a wrong password, that should be logged as an "auth" message > from PAM. > > Please describe the steps you took to install your test VM, including > any non-default settings used? For example, I wonder whether this is > locale-sensitive - I'm using en_GB.UTF-8 but you seem to be using a > non-English locale. > > If your test VM does not contain any personal or confidential data, > and you can can transfer files off it with ssh, a shared filesystem or > paste.debian.net, it would be useful to see the entire systemd journal > (starting from boot) for this procedure: > > - boot the VM > - log in as a user > - lock the screen > - unlock with a correct password > > and compare it with > <https://people.debian.org/~smcv/973474/journalctl_-b.log.gz>. > > Or if your test VM contains personal/confidential things, please could > you try to set up a similar VM without those and reproduce the bug there? > > > Is there perhaps some setting I could tweak to convince gnome-shell to > produce > > some debug output when I attempt unlocking? > > Try these: > > systemctl --user edit gnome-shell@x11.service > systemctl --user edit gnome-shell@wayland.service > sudo systemctl edit gdm.service > > and in each case, add this: > > [Service] > Environment=G_MESSAGES_DEBUG=all > > Thanks, > smcv >