[LightDM] [systemd-devel] sd 221 regression: login - nonexistent sessions via lightdm

[David Herrmann]

Hi

On Tue, Jul 7, 2015 at 10:08 PM, poma <pomidorabelisima at gmail.com> wrote:
> On 07.07.2015 19:48, David Herrmann wrote:
>> Hi
>>
>> On Tue, Jul 7, 2015 at 7:10 PM, David Herrmann <dh.herrmann at gmail.com> wrote:
>>> Hi
>>>
>>> On Tue, Jul 7, 2015 at 6:55 PM, Martin Pitt <martin.pitt at ubuntu.com> wrote:
>>>> Hey David,
>>>>
>>>> David Herrmann [2015-07-07 18:31 +0200]:
>>>>>> Revert "login: re-use VT-sessions if they already exist" - commit 0204c4b
>>>>>> http://cgit.freedesktop.org/systemd/systemd/commit/?id=0204c4b
>>>>>
>>>>> Can someone elaborate what exactly lightdm does here? We really want
>>>>> to prevent multiple sessions on the same VT. This is just nasty and
>>>>> never made any sense. So I'm really interested why lightdm doesn't
>>>>> kill it's manager-session before it starts the new session. Any
>>>>> particular reason here?
>>>>
>>>> I'll let Robert answer with the details, but something I noticed:
>>>>
>>>> It's not that simple to reproduce, but sometimes it seems the lightdm
>>>> "greeter" session (running as user lightdm, where you select user/type
>>>> password and so on) doesn't completely terminate, but some processes
>>>> stay around in it. Thus the greeter session stays around in state
>>>> "Closing", and then the "real" session starts on the same VT.
>>>>
>>>> I asked the reporter of https://launchpad.net/bugs/1472259 to attach
>>>> systemd-cgls, so that we can see what's running in the session.
>>>
>>> So it might indeed just be a race in lightdm. Hmm..
>>> Anyway, this patch here should also fix the issue (if it does, I'll
>>> commit something proper).
>>
>> Ok, I pushed this to -git now. Should be fixed. Can you guys verify?
>>
>> Thanks
>> David
>>
>
> $ loginctl list-sessions
>    SESSION        UID USER             SEAT
>          1       1001 test             seat0
>         c1        989 lightdm          seat0
>
> 2 sessions listed.
>
> $ loginctl show-session c1
> Id=c1
> Name=lightdm
> Timestamp=Tue 2015-07-07 21:44:41 CEST
> TimestampMonotonic=51125373
> VTNr=1
> Display=:0
> Remote=no
> Service=lightdm-greeter
> Scope=session-c1.scope
> Leader=1346
> Audit=0
> Type=x11
> Class=greeter
> Active=no
> State=closing
> IdleHint=no
> IdleSinceHint=0
> IdleSinceHintMonotonic=0
>
> $ loginctl show-session 1
> Id=1
> Name=test
> Timestamp=Tue 2015-07-07 21:56:10 CEST
> TimestampMonotonic=739928248
> VTNr=1
> Display=:0
> Remote=no
> Service=lightdm
> Desktop=xfce
> Scope=session-1.scope
> Leader=1983
> Audit=1
> Type=x11
> Class=user
> Active=yes
> State=active
> IdleHint=no
> IdleSinceHint=0
> IdleSinceHintMonotonic=0
>
> $ rpm -q systemd lightdm lightdm-gtk
> systemd-222-2.fc23.x86_64
> lightdm-1.15.0-2.fc23.x86_64
> lightdm-gtk-2.0.1-2.fc23.x86_64
>
> It's OK.

Much appreciated, thanks!

I'd still prefer a comment from Robert about the intended behavior.
But that's not release critical.

Thanks
David