Double logging a single time (tty1 +tty7)

[Bib]

I got a dell xps322x installed with latest 13.04 i386-64 and updates which made several times the following behaviour: I made changes that requiered a reboot (clone image to ssd or e.g. unbind Unity-greeter wallpaper from users' personnal desktop one).

On boot I got a black screen with a blinking cursor top-left and... an orphan mouse cursor crying where to clic (black screen).
So I try switching tty1~6 with Ctrl+Alt+F1~6, back to tty7 still black, so go back to tty1 and type in creds which opens the terminal OK, then switch to tty7 which I find opened !!!!
PS: the orphan mouse cursor was visible in all tty !

Don't know howto reproduce, and I can't tell if closing/locking one session does the same to the other. If this happens again I'll check this and report here.

Feel free to change the target package.

Thanks for Ubuntu
---
ApportVersion: 2.9.2-0ubuntu8.3
Architecture: amd64
DistroRelease: Ubuntu 13.04
InstallationDate: Installed on 2013-07-05 (95 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424)
MarkForUpload: True
Package: unity-greeter 13.04.2-0ubuntu1
PackageArchitecture: amd64
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=fr_FR.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 3.8.0-31.46-generic 3.8.13.8
Tags: raring
Uname: Linux 3.8.0-31-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups:

[Bib (bybeu)]

PS: the orphan mouse cursor was visible in all tty !

[Bib (bybeu)]

More on the behaviour:
on boot tty7 keeps stuck on the said black screen, but it is different of what I described in initial post:
two lines of log are shown on top:
[ 37.954403] wlan0: failed to remove key (0, 00:17:9a:75:73:ce) from hardware (-5)
[ 37.970079] wlan0: failed to remove key (1, ff:ff:ff:ff:ff:ff) from hardware (-5)
Can't do nothing here, Ctrl+C does nothing (didn't try Alt+PrtScn+K nor other B)

As soon as I log in tty1 the screen switches to tty7 graphical now opened session which seems to work OK.
I can switch back to tty1 to make sure its is still opened and I can issue commands (ls tested OK).
I can switch to other (2~6) tty but they are unstable and send me back to tty7 after a short while or just hitting Ctrl+Alt(+NothingElse).
When I GUI close tty7, Unity-greeter login screen shows OK.
Beginning now, Crtl+Alt+[F1:F7] work as intended and as usual afaics.
Having a look at tty1 shows it still opened.
How do you say bug in english :) ?

[Bib (bybeu)]

In the time elapsed since last post I found I can blindly enter my password into to black tty7 and this triggers the display of the unity desktop.

[Bib (bybeu)]

Since my previous post the issue did not show again

[Bib (bybeu)]

Hi
Some news
For the purpose of another bug report I was required to test a mainline kernel... then I forgot it.
Yesterday night I hibernated the laptop, and this morning, on thaw, I forgot (again) to select from grub the standard kernel I was working in yesterday (3.8.0-31) so I lost my session. Hopefully, regards to firefox and libreoffice session restore, not all was lost. There apport suggested to report a bug, and I was ready to do it when the popup reminded me this was related to the mainline kernel, so I discarded the submission.
So I decided to remove the mainline test kernel (sudo apt-get purge linux-image-3.12.0-031200rc3-generic).
On reboot, this 1200359 bug happened again: black screen with only the mouse arrow, and switching to tty1 showing the characters loggin prompt ***and*** the mouse cursor, in which I didn't login.
Switch back to tty7 and blindly logged in OK.
Then, just to see, switched back to tty1~6: all 6 seemed to show OK (but tty1 still showing the mouse arrow and a message stating something about system update is OK and waiting for an acquitting Enter strike, and then a blinking prompt undescore somewhere in the middle of the screen), but all tty automatically switch me back to tty7 after a very short 3-4 second amount of time. Althougth I reached to login a tty (don't remember which one) but it still auto switched me to tty7. Although again with some difficulty, I reached to quickly switch to the said ttyN and send an exit command before I was sent back to tty7.
Then I rebooted and now all I working OK, no blank black screen, no auto-switch.
This makes me think both to the grub mechanism that keeps the menu on screen when a crash happened or maybe to the tempo I set in /etc/default/grub.
I will attach the file.

[Bib (bybeu)]

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