Problems Booting 20.04.4 on a Dell Latitude 7400

[Martin_Kuemmel]

Okay usually to whatever the "Software Updater" recommends and that's how I ended up with the 5.8 kernel that had the issues on boot.

To follow the suggestion to got back to 5.4.0.67 I followed a webpage I googled and did:

sudo apt-get install linux-image-5.4.0.67-generic linux-headers-5.4.0.67-generic

The kernel showed up in grub, I booted into it and it showed the behaviour above. My did not re-install any other dependent libraries and applications. So in the end I find it understandable that not everything works when using this "old" kernel.

I guess the two last posts would lead to a clean, working installation based on 5.4.0.67. Since I experience already now the failures to boot into 5.4.0.67 described above I am somehow afraid to end up with a 5.4.0.67 based laptop that has the same problems I am having right now with 5.8.x.

So, is there still hope that I'll be able reliably boot my laptop once turning everything back to 5.4.0.67?

[kansasnoob]

Okay usually to whatever the "Software Updater" recommends and that's how I ended up with the 5.8 kernel that had the issues on boot.

To follow the suggestion to got back to 5.4.0.67 I followed a webpage I googled and did:

sudo apt-get install linux-image-5.4.0.67-generic linux-headers-5.4.0.67-generic

The kernel showed up in grub, I booted into it and it showed the behaviour above. My did not re-install any other dependent libraries and applications. So in the end I find it understandable that not everything works when using this "old" kernel.

I guess the two last posts would lead to a clean, working installation based on 5.4.0.67. Since I experience already now the failures to boot into 5.4.0.67 described above I am somehow afraid to end up with a 5.4.0.67 based laptop that has the same problems I am having right now with 5.8.x.

So, is there still hope that I'll be able reliably boot my laptop once turning everything back to 5.4.0.67?

I'm trying to get you back to the state you were in May 2020 with 20.04:

https://ubuntuforums.org/showthread....2443622&page=2

At that time 20.04 would have been running the 5.4 series kernel and you said all was well. What I'm recommending now should not create any new problems, but I would avoid removing any kernels until we have a 5.4 series kernel working properly. I suspect you may be missing something like the appropriate "linux-modules-extra" packages.

Just installing a specific kernel can create problems that's why we need to install 'linux-generic' with all of its "depends" and "recommends" so we know we're working with a complete kernel. Installing 'linux-generic' may well remove 'linux-generic-hwe' but right now we don't care about that. Those are just meta-packages to ensure we're not missing any dependencies and also to ensure proper updates to the series kernel we use so we're getting all the proper security updates. Like just yesterday most of my machines got the update to 5.4.0.70.73 just through the software-updater.

[Martin_Kuemmel]

Thanks for the explanation. This all makes sense, and I will tackle that during the weekend after generating the necessary backups and so on.
I'll post the result, of course!

[Martin_Kuemmel]

I did as suggested in #10. After a reboot everything works, which is great!
The newest kernel is -70, and #11 applied to that gives:

mkuemmel@bruce-2:~$ dpkg --list | grep 5.4.0-70
ii  linux-headers-5.4.0-70                     5.4.0-70.78                           all          Header files related to Linux kernel version 5.4.0
ii  linux-headers-5.4.0-70-generic             5.4.0-70.78                           amd64        Linux kernel headers for version 5.4.0 on 64 bit x86 SMP
ii  linux-image-5.4.0-70-generic               5.4.0-70.78                           amd64        Signed kernel image generic
ii  linux-libc-dev:amd64                       5.4.0-70.78                           amd64        Linux Kernel Headers for development
ii  linux-modules-5.4.0-70-generic             5.4.0-70.78                           amd64        Linux kernel extra modules for version 5.4.0 on 64 bit x86 SMP
ii  linux-modules-extra-5.4.0-70-generic       5.4.0-70.78                           amd64        Linux kernel extra modules for version 5.4.0 on 64 bit x86 SMP

I rebooted a couple of times (maybe 4), which for me is "Power off" and then switch on again. I did that with and without the dockingstation plugged in, and it worked.

Then I tried "Reboot". The mechanics is as with "Power off", I go the grub menu and select the -70 kernel. But it did not reboot. I tried a couple of times in various kernels, no way.

I tried in recovery mode, and it works (but my dockingstation not). I try with the dockingstation plugged in, and it works (including the dockingstation).

As kind of a summary:

• my laptop works with kernel 5.4.0-70.78
• one reliable way to boot is to go for the recovery mode
• the other reliable way to boot is with the dockingstation plugged in
• when hitting "Reboot" the laptop does not boot

The situation is not so bad, but also not much different than it was with the 5.8 kernel. I'll consolidate the systematics on when I can boot and when not with a few tries. Apart from that I am still happy for suggestions to improve the situation. The problem is not straight forward, but it is not straight forward since a year, and the fact that the Dell'ies could not find a solution might confirm that as well.

[Martin_Kuemmel]

Okay, the software update wants do install both new 5.4 and 5.8 kernels. I think it is time to get rid of the 5.8 kernels that are still on my system.

Could someone help me and tel me ho to de-install the 5.8 kernels?

Thanks.

[deadflowr]

Could someone help me and tel me ho to de-install the 5.8 kernels?

You can remove the linux-generic-hwe-20.04 meta-package.
(Also check that removing that also removes both the linux-image-generic-hwe-20.04 and linux-headers-generic-hwe-20.04 meta-packages,
if it doesn't also remove those then mark those for removal too)
Removing those will stop it from trying installing the newer 5.8 kernels.

After that you might want to try manually removing any 5.8 kernels that are installed.