logind session ID not used due to race condition
| Affects | Status | Importance | Assigned to | Milestone | |
|---|---|---|---|---|---|
| Light Display Manager |
Fix Released
|
High
|
Robert Ancell | ||
| 1.10 |
Fix Released
|
High
|
Robert Ancell | ||
| lightdm (Ubuntu) |
Fix Released
|
Critical
|
Robert Ancell | ||
| Trusty |
Fix Released
|
High
|
Robert Ancell | ||
| Utopic |
Fix Released
|
Critical
|
Robert Ancell | ||
Bug Description
[Impact]
Sometimes a session will fail to get the logind session ID to pass back to the LightDM daemon. This appears to be due to a race using the D-Bus method org.freedesktop
This bug was detected by a bug in LightDM 1.11.7 where the daemon would attempt to read both a logind and ConsoleKit ID when this D-Bus call failed.
The solution is to use the XDG_SESSION_ID environment variable and not GetSessionByPID() and to fix the passing of the session id(s) from the session to the daemon to be unambiguous.
[Test Case]
Check the LightDM log always contains lines like:
[+0.78s] DEBUG: Activating login1 session c1
for each session.
[Regression Potential]
Change is non-trivial and could cause other bugs. Regression tests confirm existing test cases work.
| Changed in lightdm (Ubuntu): | |
| importance: | Undecided → High |
| Ricardo Salveti (rsalveti) wrote | #1 |
| Ricardo Salveti (rsalveti) wrote | #2 |
| Ricardo Salveti (rsalveti) wrote | #3 |
| Ricardo Salveti (rsalveti) wrote | #4 |
| Ricardo Salveti (rsalveti) wrote | #5 |
| Ricardo Salveti (rsalveti) wrote | #6 |
| Ricardo Salveti (rsalveti) wrote | #8 |
| Changed in lightdm (Ubuntu): | |
| assignee: | nobody → Robert Ancell (robert-ancell) |
| importance: | High → Critical |
| status: | New → Triaged |
| Changed in lightdm: | |
| status: | New → Triaged |
| importance: | Undecided → High |
| assignee: | nobody → Robert Ancell (robert-ancell) |
| Launchpad Janitor (janitor) wrote | #9 |
| Changed in lightdm (Ubuntu): | |
| status: | Triaged → Fix Released |
| Changed in lightdm: | |
| milestone: | none → 1.11.8 |
| status: | Triaged → Fix Released |
| summary: |
- Krillin fails to display spinner/unity8 after upgrade to 1.11.7-0ubuntu1 + logind session ID not used due to race condition |
| Changed in lightdm (Ubuntu Trusty): | |
| importance: | Undecided → Medium |
| status: | New → In Progress |
| assignee: | nobody → Robert Ancell (robert-ancell) |
| importance: | Medium → High |
| description: | updated |
| description: | updated |
| description: | updated |
| Robert Ancell (robert-ancell) wrote | #10 |
| Mathew Hodson (mhodson) wrote | #11 |
| Changed in lightdm (Ubuntu Trusty): | |
| status: | In Progress → Fix Committed |
| tags: | added: verification-needed |
| Mathew Hodson (mhodson) wrote | #12 |
| Robert Ancell (robert-ancell) wrote | #13 |
| tags: |
added: verification-done removed: verification-needed |
| Launchpad Janitor (janitor) wrote | #14 |
| Changed in lightdm (Ubuntu Trusty): | |
| status: | Fix Committed → Fix Released |
root@ubuntu-
[+0.00s] DEBUG: Logging to /var/log/
[+0.00s] DEBUG: Starting Light Display Manager 1.11.7, UID=0 PID=1323
[+0.00s] DEBUG: Loading configuration dirs from /usr/share/
[+0.00s] DEBUG: Loading configuration from /usr/share/
[+0.00s] DEBUG: Loading configuration from /usr/share/
[+0.00s] DEBUG: Loading configuration from /usr/share/
[+0.00s] DEBUG: Loading configuration from /usr/share/
[+0.00s] DEBUG: Loading configuration dirs from /custom/
[+0.00s] DEBUG: Loading configuration dirs from /etc/xdg/
[+0.00s] DEBUG: Loading configuration from /etc/lightdm/
[+0.00s] DEBUG: Loading configuration from /etc/lightdm/
[+0.00s] DEBUG: Using D-Bus name org.freedesktop
[+0.01s] DEBUG: Registered seat module xlocal
[+0.01s] DEBUG: Registered seat module xremote
[+0.01s] DEBUG: Registered seat module unity
[+0.06s] DEBUG: Monitoring logind for seats
[+0.06s] DEBUG: New seat added from logind: seat0
[+0.06s] DEBUG: Seat seat0: Starting
[+0.07s] DEBUG: Using VT 1
[+0.07s] DEBUG: DisplayServer: Logging to /var/log/
[+0.07s] DEBUG: Launching process 1369: /usr/share/
[+0.07s] DEBUG: DisplayServer: Waiting for system compositor for 60s
[+0.07s] DEBUG: Acquired bus name org.freedesktop
[+0.07s] DEBUG: Registering seat with bus path /org/freedeskto
[+0.30s] DEBUG: Loading users from org.freedesktop
[+0.30s] DEBUG: User /org/freedeskto
[+1.43s] DEBUG: DisplayServer: READY
[+1.43s] DEBUG: DisplayServer: Compositor ready
[+1.43s] DEBUG: Seat seat0: Compositor ready
[+1.43s] DEBUG: Seat seat0: Creating user session
[+1.43s] DEBUG: Seat seat0: Creating display server of type mir
[+1.44s] DEBUG: Seat seat0: Display server ready, starting session authentication
[+1.44s] DEBUG: Session pid=1623: Started with service 'lightdm-
[+1.50s] DEBUG: Session pid=1623: Authentication complete with return value 0: Success
[+1.50s] DEBUG: Seat seat0: Session authenticated, running command
[+1.50s] DEBUG: Registering session with bus path /org/freedeskto
[+1.51s] DEBUG: Session pid=1623: Running command /usr/sbin/
[+1.51s] DEBUG: Creating shared data directory /var/lib/
[+1.51s] DEBUG: Session pid=1623: Logging to .xsession-errors
root@ubuntu-
Warning: ignoring unrecognised arguments: --vt 1
GL_VENDOR = ARM
GL_RENDERER = Mali-400 MP
GL_VERSION = OpenGL ES 2.0
dm_connection_start
WARNING: QApplication was not created in the main() thread.
initialized brightness parameters
Opening session session-0