Arch Linux

NBonaparte

Member

Registered: 2015-04-17

Posts: 12

LightDM still running after unlock

After successfully unlocking LightDM (locked with dm-tool lock), the process lightdm-gtk-greeter is still running after the WM (Openbox) appears. Locking and unlocking several times more results in more lightdm-gtk-greeter processes, each of which take considerable amounts of memory. I usually have to manually kill the processes.

How can I prevent this from occurring?

andreyv

Member

From: Riga, Latvia

Registered: 2012-11-02

Posts: 34

Re: LightDM still running after unlock

I just wanted to report the same thing. I use LightDM, lightdm-gtk-greeter and light-locker. After some locks/unlocks "loginctl list-sessions" shows something like

   SESSION        UID USER             SEAT            
       c13        620 lightdm          seat0           
        c2       1000 andrey           seat0           
       c12        620 lightdm          seat0           
       c14        620 lightdm          seat0           

4 sessions listed.

and I have to run "sudo loginctl terminate-session <session>" to kill all these greeter sessions.

This only started recently, there was no such problem a few weeks ago.

nbvcxz

Member

From: Poland

Registered: 2007-12-29

Posts: 202

Re: LightDM still running after unlock

After successfully unlocking LightDM (locked with dm-tool lock), the process lightdm-gtk-greeter is still running after the WM (Openbox) appears. Locking and unlocking several times more results in more lightdm-gtk-greeter processes, each of which take considerable amounts of memory. I usually have to manually kill the processes.

Same here about multiplied lightdm. Moreover lightdm starts at-spi2-core although I have

NO_AT_BRIDGE=1
GNOME_ACCESSIBILITY=0

in my /etc/environment. Any ideas how to force lightdm to as before 1.14 version (I mean single instance and no accessibility tools).

---

Lenovo G50 | LXQT-git | compton | conky

andrew_the_p

Member

From: BY

Registered: 2015-03-17

Posts: 16

Re: LightDM still running after unlock

Could you provide some additional information?
1. `ps` output with multiple lightdm/lightdm-gtk-greeter instances
2. LightDM log: /var/log/lightdm/lightdm.log
3. Greeter log: /var/log/lightdm/x-*-greeter.log (the newest one, and add "allow-debugging" option to greeter config).

NO_AT_BRIDGE=1

This option is hardcoded to greeter source code to prevent described situation + greeter terminates its own at-spi instance at exit. Just strange that it doesn't work in your case.

Is it similar to this bug?

andreyv

Member

From: Riga, Latvia

Registered: 2012-11-02

Posts: 34

Re: LightDM still running after unlock

Hello,

Yes, this is similar, though I never allowed it go up to 7 instances and don't know what happens then.

Here is the requested information after logging in and locking/unlocking one time:

ps output: http://pastie.org/private/sibatkccsbbareu4qjes8w
lightdm.log: http://pastie.org/private/fnshhcoo4noyf91unskiq
x-0-greeter.log: http://pastie.org/private/neihqit2ohibvglfrj7mgg
x-1-greeter.log (should correspond to the greeter that is left running): http://pastie.org/private/gyjpkjpxnckklng1dd6hg

Should I post this information in the mentioned bug report?

EDIT: I suppose the most interesting part is lightdm.log after I switch to the VT where the greeter is left running: http://pastie.org/private/t9xnlxaewelwpijm7agta

As soon as I do the switch, the greeter exits and then lightdm starts a new one.

Last edited by andreyv (2015-04-22 17:17:23)

NBonaparte

Member

Registered: 2015-04-17

Posts: 12

Re: LightDM still running after unlock

Is it similar to this bug?

I have discovered that after several logins the WM freezes, but I have not managed to count how many logins it takes.
It could possibly be the same issue, maybe.

PieterGen

Member

From: Groningen, NL, EU

Registered: 2012-01-18

Posts: 59

Re: LightDM still running after unlock

I have no answer but I like your user name, NBonaparte !

maurizeio

Member

Registered: 2015-04-25

Posts: 3

Re: LightDM still running after unlock

Hello,
Manjaro user here. Having encountered this issue after last update, I started investigate the involved packages. I discovered that downgrading gtk3 from version 3.16 to 3.14 (that present before the update) is a possible workaround. Note that, if you are using pamac, you'll have to downgrade that too since the last version depends on gtk3>=3.16. Alternatively, you can switch to octopi.

NBonaparte

Member

Registered: 2015-04-17

Posts: 12

Re: LightDM still running after unlock

Thanks for informing us.
I downgraded gtk3, and indeed, lightdm-gtk-greeter does not run after unlocking.

NBonaparte

Member

Registered: 2015-04-17

Posts: 12

Re: LightDM still running after unlock

Apparently lightdm has been updated to 1.14.0-2. I have updated it and reverted to the current version of gtk3 (as I downgraded before), but the problem persists (with gtk 3.16).

andrew_the_p

Member

From: BY

Registered: 2015-03-17

Posts: 16

Re: LightDM still running after unlock

It's change in gtk, not in lightdm. Somewhere between 3.15.0 and 3.15.5.
1. Greeter catches SIGTERM signal from lightdm
2. Tries to stop main gtk loop by calling gtk_main_quit()
3. Nothing happens if gtk version > 3.15.0
Maybe some gdk issue - I'll check Gtk changelog, but it will take some time.
There is a simple workaround - killing greeter instance in its SIGTERM handler. But it's just not nice solution.

Last edited by andrew_the_p (2015-04-29 03:51:50)

andrew_the_p

Member

From: BY

Registered: 2015-03-17

Posts: 16

Re: LightDM still running after unlock

LightDM leaves a systemd session after login

Last edited by andrew_the_p (2015-05-03 18:16:10)

andreyv

Member

From: Riga, Latvia

Registered: 2012-11-02

Posts: 34

Re: LightDM still running after unlock

Thanks for investigating this!

I noticed that the greeter closes immediately once I switch again to the corresponding VT after unlock (see comment #5 here). Is it possible that XSync() is waiting for the VT to become active and only then returns to the caller?

maurizeio

Member

Registered: 2015-04-25

Posts: 3

Re: LightDM still running after unlock

LightDM leaves a systemd session after login

I can confirm this issue is present also with gtk3 3.14.9 (which instead prevents the first one discussed) so it's probably unrelated.

Last edited by maurizeio (2015-05-03 20:28:42)

andrew_the_p

Member

From: BY

Registered: 2015-03-17

Posts: 16

Re: LightDM still running after unlock

I noticed that the greeter closes immediately once I switch again to the corresponding VT after unlock (see comment #5 here). Is it possible that XSync() is waiting for the VT to become active and only then returns to the caller?

I don't know what is the real source of the problem, it's out of my knowledge.

andrew_the_p

Member

From: BY

Registered: 2015-03-17

Posts: 16

Re: LightDM still running after unlock

Yep, looks like two different bugs. It's definitely worse than one.

You can test temporary workaround for many-VTs-bug, just use PKGBUILD from AUR with this branch:
lp:~lightdm-gtk-greeter-team/lightdm-gtk-greeter/lp-1445461-leave-instance

maurizeio

Member

Registered: 2015-04-25

Posts: 3

Re: LightDM still running after unlock

Thanks for your help, andrew.

andreyv

Member

From: Riga, Latvia

Registered: 2012-11-02

Posts: 34

Re: LightDM still running after unlock

You can test temporary workaround for many-VTs-bug, just use PKGBUILD from AUR with this branch:
lp:~lightdm-gtk-greeter-team/lightdm-gtk-greeter/lp-1445461-leave-instance

I applied this patch to the latest stable lightdm-gtk-greeter release. It works — no more rogue greeter processes are left.

andrew_the_p

Member

From: BY

Registered: 2015-03-17

Posts: 16

Re: LightDM still running after unlock

The patch changed slightly, PKGBUILD.

andreyv

Member

From: Riga, Latvia

Registered: 2012-11-02

Posts: 34

Re: LightDM still running after unlock

The revised patch works as well.

Korrode

Member

From: Australia

Registered: 2009-11-02

Posts: 110

Re: LightDM still running after unlock

I've just applied andrew_the_p's branch changes to the 2.0 release of lightdm-gtk-greeter and added it to Manjaro's unstable and testing branches.
(There was some fuzz with one hunk when applying the patch to the 2.0 release, but it looks inconsequential.)

It seems to be working fine for me, thanks Andrew.

If the packager for Arch (Maxime) would like the new package source, it's here:
Package source
Diff to current Arch package source

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xfce | compiz | gmrun | urxvt | chromium | geany | aqualung | vlc | geeqie

NBonaparte

Member

Registered: 2015-04-17

Posts: 12

Re: LightDM still running after unlock

Has anyone had any issues with the latest update of lightdm (1.14.0-3) and lightdm-gtk-greeter (branch patch)? It seems that I cannot use dm-tool at all, as there is nothing happens. After downgrading lightdm to the previous version it seems to work fine.
Does this apply to just the patched version of gtk-greeter or is it for all versions?

Korrode

Member

From: Australia

Registered: 2009-11-02

Posts: 110

Re: LightDM still running after unlock

lightdm-gtk-greeter 2.0.1 has been released, i've flagged Arch's package out of date.

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xfce | compiz | gmrun | urxvt | chromium | geany | aqualung | vlc | geeqie

Alucryd

Developer

From: France

Registered: 2011-05-07

Posts: 110

Website

Re: LightDM still running after unlock

2.0.1 is up, thx guys. Should fix this one as well: https://bugs.archlinux.org/task/43999

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The bird of Hermes is my name, eating my wings to make me tame.

Chazza

Wiki Maintainer

Registered: 2013-06-02

Posts: 506

Re: LightDM still running after unlock

v2.0.1 doesn't completely fix the greeter processes problem for me. The problem of multiple greeter processes is gone but I have noticed that one greeter process will remain running after authenticating.