I have what I believe is the same problem. I have an Ubuntu 12.04 with encrypted filesystem, which started displaying the problem after upgrading to 15.04.
Bizarrely, the screen turns on and correctly shows the encryption password prompt if I hit the "down" arrow on the keyboard, but not when hitting any other key. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1030094 Title: LVM encrypted, screen turned off after grub To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/plymouth/+bug/1030094/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs