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Question

I have a fresh install of Ubuntu 14.04.1.

I tried to boot into it several times, waiting >4 minutes each time, and saw only a fat blinking cursor in the upper left.

I chrooted into the OS from a LiveCD flash stick, updated all packages, and told GRUB to give me the debugging output.

I tried booting again and got this screen:

~4 minutes later, this came up:

A reasonable (albeit untimed) amount of additional waiting did not result in additional messages.

I've searched my /var/log files for the key words here, but apparently the log was not saved.

Installing bootchart did not yield a log either.

I'm not sure what to do, but am considering installing an older kernel.

Any thoughts as to what the issue might be?

Answer

So, I found a way to get things booted: downgrade the kernel.

The kernel that came with 14.04.1 was 3.13.0-32-generic. The kernel that worked was 3.13.0-24-generic. It is available in the repositories.

How to get it?

Boot from a LiveCD/flash drive and open a terminal.

Now, we need to load ourselves into the computer's new, non-functional OS:

sudo mount /dev/sda1 /mnt
sudo mount --bind /dev /mnt/dev
sudo mount --bind /proc /mnt/proc
sudo mount --bind /sys /mnt/sys
sudo chroot /mnt

After the final command all commands you type are now executed as though you had actually booted up the computer. This is handy, because it means we can use:

sudo apt-get update
sudo apt-get upgrade

To grab the latest packages and install them.

We can think downgrade the kernel with:

sudo apt-get install linux-image-3.13.0-24-generic
sudo apt-get install linux-image-extra-3.13.0-24-generic

We can then be sure that GRUB is updated using:

sudo update-grub

If initramfs complains about things, you may need to run:

sudo update-initramfs

But this is unlikely.

After installing the kernel and updating grub, reboot.

Start-up will probably fail again by showing a blank screen or one with a single blinking cursor in the upper left. Ctrl+Alt+Delete to restart a second time.

Now, the GRUB menu will show. Head to Advanced Options for Ubuntu, and boot into the older kernel. After this, things booted just fine for me.