2

I've just installed a fresh ubuntu 16.04 and run apt-get upgrade, which apparently resulted in linux 4.4.0-22 being installed.

On reboot, after I select ubuntu from the menu (I have Windows installed as well on a different disk), I get a blinking cursor. The boot hangs here indefinitely.

I tried manually selecting linux 4.4.0-15 from the "advanced" menu in grub and it boots fine.

Attached is a poor man's screenshot of where the boot hangs when I select the 4.4.0-22 kernel recovery mode:

enter image description here

Are any of these errors?

Note: The 4.4.0-15 kernel is failing now as well, and I've been able to sometimes get to a login prompt with 4.4.0-20. It seems to depend on the way the wind is blowing. Windows is working fine.

I have started removing physical devices from my PC to see if it's a hardware issue. I've been able to boot using the default 4.4.0-20 kernel after removing some memory and 2 hard disks. It's too early to tell if I just got lucky though.

quant
  • 762
  • No, looks good to me. For what it's worth, on my system, the next step is the loading of the Linux agpgart interface. Perhaps you could try to boot without the agpgart module. You do that by adding agpgart to the list of blacklisted modules in /etc/modprobe.d/blacklist.conf. – Jos May 12 '16 at 10:45
  • 1
    I bet your system has actually booted and the GUI is crashing. Try i) hitting Alt+F2 or Alt+F3 or so and see if that gets you to a login prompt and ii) press e (the E key) at the grub menu, and remove the "splash" and "quiet" options from the kernel boot line. Does that let you boot straight to a login prompt? – terdon May 12 '16 at 13:50
  • @terdon I tried removing quiet and splash. The effect was that I now got stuck on the purple screen just after grub instead. Those key combinations had no effect. – quant May 12 '16 at 21:59
  • @quant try ctrl+alt+F1 or F2 instead. Does that bring you to a prompt? – terdon May 12 '16 at 22:03
  • @Jos I just tried adding agpgart to the blacklist, without any effect. – quant May 12 '16 at 22:04
  • @terdon no it doesn't. – quant May 12 '16 at 22:05

2 Answers2

1

I've had a few problems with upgrading Ubuntu 16.04 . I never found out the reason but my "guess" has been that it's a problem with the upgrade and not really something wrong with the kernel or Ubuntu 16.04 for my system.

What you can consider is creating a boot disk and boot off of it. Select "Try Ubuntu". I guess this should work. If it does, it at least means that the kernel and Ubuntu 16.04 will work for your system.

Maybe some left-over settings is causing you problems. From here, you can consider the following to re-install Ubuntu:

  1. Mount your root partition and copy system-level files to your home directory. For example, at least everything from /etc.
  2. Select "Install Ubuntu" and one of the options available in Ubuntu 16.04 is to write over your existing Ubuntu, leaving your /home directory intact.
  3. It will wipe the system-level files and install a base system.
  4. Yes, now you have to go through and install all the missing packages. Hopefully, you don't have to stress out what settings you need to edit and just copy over the configuration file(s) from the old /etc.

I wouldn't be stingy with step (1). Copy any settings in /var and so on if you think it would take some time to recover. Just make sure you put it in your home directory. Other parts of the system will be wiped.

Hopefully, this should work. Yes, it's a bit heavy-handed, but I've done this a couple of times (on different systems) for Ubuntu 16.04 already. Trying to figure out the cause is better, but sometimes, you don't have the time...

Ray
  • 2,071
  • Hi Ray, this is for a fresh Ubuntu install. I completely formated the disk before installing. Booting off a USB works fine, but I think the installer for 16.04 has a different kernel version. I say this because this issue only appeared once I did apt-get upgrade, which included a kernel update. I'm starting to think this could be hardware related. – quant May 14 '16 at 04:56
  • My apologies! It's the first sentence of your post and I completely missed it! Kernels get updates every few weeks. What if you hold off updating until a few have passed? It's always possible that an update has introduced a bug... – Ray May 14 '16 at 05:06
  • Sorry, clicked "Add Comment" too soon. You should be able to select the kernel from the grub menu. Just set it to the older one, and once you're in, uninstall the latest one. and then, try to resist the temptation to upgrade for a few weeks (at least until another kernel has appeared in the repository). – Ray May 14 '16 at 05:08
  • That's probably a good idea. Interestingly I've not had issues since removing some ram and hard disks (physically) , so maybe it's a driver module that's getting stuck? – quant May 14 '16 at 05:08
  • There is a way to do an update of all software except the kernel. I haven't done something like this for a while, but you can consider looking at this: (http://askubuntu.com/questions/678630/how-can-i-avoid-kernel-updates) Hopefully, at some point, whatever problem you're encountering with your hardware will be addressed. Personally, I don't have the skills to sort out such problems with kernels -- if I were, of course, I'd try to find out the cause and report it as a bug report... – Ray May 14 '16 at 05:12
0

You can also try the 4.6 kernel. I found this guide to be quite helpful but I had to match the kernel number to the one found here. Essentially I changed just the last 6 digits, which I assume represent the build date.

I'm sorry to say that the 4.6 kernel still has the same problem on my machine. If yours does as well, we should try matching up components to see what is causing the issue. I would hate to be unable to update to a new version of Ubuntu, and that might happen if we have the same issue and it doesn't get fixed.

fossfreedom
  • 172,746
dlpolanco
  • 3