Plymouth text-mode splash causes X to crash on first run due to shared tty7
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
X.Org X server |
Invalid
|
Undecided
|
Unassigned | ||
plymouth (Ubuntu) |
Fix Released
|
High
|
Scott James Remnant (Canonical) | ||
xorg-server (Ubuntu) |
Invalid
|
Undecided
|
Unassigned |
Bug Description
Binary package hint: plymouth
Lucid adopted the Plymouth graphical splash service that uses the Kernel Mode Setting (KMS) facilities to provide a flicker-free graphical splash during start-up. For older video chipsets and drivers (e.g. intel i815) that *do not* support KMS plymouth falls back to using a text console (using the text plugin). It attaches to tty7 and outputs Linux terminfo control codes to draw a colour progress-bar at the bottom of the display.
There is an unfortunate interaction between plymouth and X. X also uses tty7. When the X/GDM log-in screen appears for the first time plymouth is still running. A script triggers a quit message to the plymouth daemon. It seems that plymouth is waiting for either the "2" key or "Enter" key to be pressed, whereupon a SIGQUIT (signal 3) is sent to tty7. This causes both plymouth *and* X to terminate.
So, if a password contains "2" or the user logs in by pressing "Enter" after typing their password, the user experience is that X 'crashes' (however, gdb reveals that X receives SIGQUIT).
Some stray plymouth control codes can be witnessed on tty7 if X is stopped and tty7 console is on-screen.
Upstart (/sbin/init) then restarts gdm (which launches X) and the second session performs correctly.
*** A temporary workaround is to disable the plymouth-splash upstart job ***
sudo mv /etc/init/
affects: | xorg (Ubuntu) → xorg-server (Ubuntu) |
tags: | added: crash |
Changed in xorg-server (Ubuntu): | |
status: | New → Confirmed |
Changed in plymouth (Ubuntu): | |
status: | New → Confirmed |
importance: | Undecided → High |
assignee: | nobody → TJ (intuitivenipple) |
Changed in xorg-server (Ubuntu): | |
status: | In Progress → Confirmed |
summary: |
- Xorg crashed at first login attempt + Plymouth text-mode splash causes X to crash on first run due to shared + tty7 |
Changed in xorg-server: | |
status: | New → Invalid |
Changed in plymouth (Ubuntu): | |
milestone: | none → ubuntu-10.04-beta-1 |
assignee: | nobody → Scott James Remnant (scott) |
Changed in plymouth (Ubuntu): | |
status: | In Progress → Fix Released |
Changed in plymouth (Ubuntu): | |
status: | Fix Released → New |
Changed in plymouth (Ubuntu): | |
status: | New → Fix Released |
tags: | added: iso-testing |
This appears to be caused by stty calls in the init scripts that reset the isig flag on the current VT, which means the VT gets a SIGQUIT when Enter is pressed. I'm working on trying to confirm this scenario is the cause.
References:
http://<email address hidden> /msg07800. html people. gnome.org/ ~michael/ blog/2009- 05-29.html
http://