Comment 46 for bug 966480

> at the time the plymouth upstart jobs were written, plymouthd was only forking
> once - and correctly opening its socket before detaching from the foreground.

This is not correct. main.c:main calls ply_create_daemon before start_boot_server, so the process does fork before binding the port.

When the error occurs the plymouthd log states:

        [main.c] on_display_message:not displaying message Please remove installation media and close the tray (if any) then press ENTER: as no splash

Note "not displaying message... as no splash". That error message only occurs when the splash screen is not being shown. It is not related to unmounting the filesystem.

> And considering we're discussing a problem that occurs only on shutdown -
> there have been no problems with reliability of plymouth splash appearing on
> boot due to a corresponding race condition - I don't think this is at all a
> likely explanation for the behavior.

Boot and shutdown are different. On boot, plymouth.conf executes plymouthd, then plymouth-splash.conf executes plymouth show-splash. On shutdown, plymouth-shutdown.conf executes both plymouthd and plymouth. Since one script executes both, the timing is tighter.

I have tested the patch and it works.