Comment 5 for bug 1200359

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.