How to fix Ubuntu 20.04 upgrade 5.8.0-

Question

I have the dell xps laptop. It was delivered with Windows 10, but I wiped that to install Ubuntu 18.04 which was fine. Last year, I did the upgrade to ubuntu 20.04. It worked pretty well except for a lot of messages on shutdown about devices not disconnecting. Different messages sometimes. When starting, there was always the disk check.

Today, I did "apt upgrade", there were 42 upgrades. This is after being up to date with updates and upgrades yesterday. So, 42 new updates in the past day... seemed high in retrospect. Now, I cannot boot normally into my OS. I get the encryption password screen, but after that just hangs with Dell and Ubuntu logo.

Hard reboot, esc, I get to a boot page. My choices are Ubuntu, with Linux 5.8.0-34 generic Ubuntu, with Linux 5.8.0-34 generic (recovery) Ubuntu, with Linux 5.4.0-59 generic Ubuntu, with Linux 5.4.0-59 generic (recovery)

If I boot with 5.4.0-59 generic, I can get in and everything looks the same as before. So, that is my workaround in the meantime.

Solution 1

I can also confirm that Ubuntu 20.04.1 upgraded to Linux 5.8.0-34.

$ cat /etc/os-release
NAME="Ubuntu"
VERSION="20.04.1 LTS (Focal Fossa)"
...

$ inxi -r
Repos:     Active apt repos in: /etc/apt/sources.list 
           1: deb http://hr.archive.ubuntu.com/ubuntu/ focal main restricted
           2: deb http://hr.archive.ubuntu.com/ubuntu/ focal-updates main restricted
           3: deb http://hr.archive.ubuntu.com/ubuntu/ focal universe
           4: deb http://hr.archive.ubuntu.com/ubuntu/ focal-updates universe
           5: deb http://hr.archive.ubuntu.com/ubuntu/ focal multiverse
           6: deb http://hr.archive.ubuntu.com/ubuntu/ focal-updates multiverse
           7: deb http://hr.archive.ubuntu.com/ubuntu/ focal-backports main restricted universe multiverse
           8: deb http://archive.canonical.com/ubuntu focal partner
           9: deb http://security.ubuntu.com/ubuntu focal-security main restricted universe multiverse

In /var/log/apt/term.log I can find the following:

Selecting previously unselected package linux-image-5.8.0-34-generic.
Preparing to unpack .../46-linux-image-5.8.0-34-generic_5.8.0-34.37~20.04.2_amd64.deb ...
Unpacking linux-image-5.8.0-34-generic (5.8.0-34.37~20.04.2) ...

apt-cache shows the following about the new kernel package:

$ apt-cache showpkg linux-image-5.8.0-34-generic
Package: linux-image-5.8.0-34-generic
Versions: 
5.8.0-34.37~20.04.2 (/var/lib/apt/lists/hr.archive.ubuntu.com_ubuntu_dists_focal-updates_main_binary-amd64_Packages) (/var/lib/apt/lists/security.ubuntu.com_ubuntu_dists_focal-security_main_binary-amd64_Packages) (/var/lib/dpkg/status)
...

So, it seems the new kernel came from an official repository. See also: https://packages.ubuntu.com/focal/linux-image-5.8.0-34-generic https://packages.ubuntu.com/focal-updates/linux-image-5.8.0-34-generic

My problem is that the Ubuntu desktop environment (GNOME) fails to start after the Linux kernel upgrade. With Linux 5.4.0-59-generic it works fine.

As suggested by guiverc I removed support for HWE stack on Ubuntu 20.04. The following articles were useful in that regard: Disable HWE and continue with GA kernal of 16.04? https://wiki.ubuntu.com/Kernel/LTSEnablementStack

$ sudo apt install linux-generic
$ sudo apt remove linux-image-5.8.0-34-generic linux-headers-5.8.0-34-generic linux-modules-5.8.0-34-generic linux-modules-extra-5.8.0-34-generic linux-hwe-5.8-headers-5.8.0-34 linux-generic-hwe-20.04

After reboot the system is back on Linux 5.4.0-59-generic and "apt update" does not offer upgrade to Linux 5.8 any more.

Solution 2

I just ran into the same problem with my notebook (Ryzen 4 + rtx2060). The cause was the custom GRUB flags "nomodeset amdgpu.dc=0" I was using.

I restored the /etc/default/grub to its default, ran sudo update-grub and everything is running again.

Plus kernel 5.8 and nvidia drivers 460 fixed almost every issue I had (black screen after suspend, hdmi not working, many games not running).

Hope it helps

Comments

[guiverc]

Are you running Ubuntu 20.04? Ubuntu 20.04 is currently at 20.04.1, and the 5.8 kernel doesn't complete testing and become stable until 20.04.2, so a Ubuntu 20.04 LTS system should still be using the 5.4 kernel? so why do you have the 5.8 kernel? Are you instead running Pop or another OS?

[guiverc]

A standard 20.04 install will use the 5.4 kernel, however if HWE edge is enabled, 5.8 will be installed already; edge causes the testing kernel to be installed (stable users still use 5.4)

[Archisman Panigrahi]

@guiverc There is another recent question on Kernel 5.8.0-34. This may be a bug. Edit: I found another askubuntu.com/questions/1305559/…

[guiverc]

@ArchismanPanigrahi I've seen 7 questions today (here, IRC etc) on 5.8 kernel on focal. I suspect now there is an instruction on some blog somewhere telling people to use the HWE edge kernel as a fix for something.. and it's now biting the users who enabled it because of an ordinary update (and their prior fix enabling testing software & edge kernel)

[faleh]

I've got two 20.04.1 systems and both have linux-generic-hwe-20.04 installed, Not sure how, maybe that was a dependency that got installed or something. However, both had this 5.8 after doing apt update, and both lost Wi-Fi (bcmwl). Others reporting loss of Wi-Fi, e.g., Launchpad bug #1907445.

[Pilot6]

@guiverc The hwe kernel moved to 5.8 today. It always happens around this time of a year. But how people get linux-generic-hwe-20.04 is a mystery to me. It was pointing to the same driver as linux-generic till today and could't fix anything. I have around 10 computers with 20.04 and none had the hwe meta. I have one with a Ryzen and was waiting for this switch to remove the edge. It's very strange. I don't see that the 20.04.1 image has it.

[Scott Bowers]

Hello, OP here. I did not purposefully go to the 5.8 kernel. It was installed through apt update && apt upgrade. If there is some way that I did this through the UI or through the update, then it could have happened that way. I am not an expert linux user, so I don't try anything fancy. Says at cat /etc/os-release that I have Ubuntu 20.04.1. Every few weeks I do apt upgrade. Sometimes, there is a UI popup to update software, so I do that. So we got to my state through one of those methods.

[guiverc]

All boxes I have access to with 20.04 on them (including a QA-test install using yesterday's 20.04.2 daily) have only the 5.4 kernel installed (HWE is still not default kernel) but the following may be helpful - sudo apt install linux-generic linux-generic-hwe-20.04- (Sorry I've nothing to test it on, nor a box to look at what is installed & thus what issues you may experience, as no focal boxes I have have HWE kernels) thanks @sarnold

[Sébastien Serre]

Thank you, you saved me !