Boot hangs with Ubuntu 20.04 on Lenovo ThinkPad L390

Hi Erwin. It looks like this ThinkPad was only certified to work with a special 18.04 OEM image, but you can try installing a kernel that may include whatever fixes went into this OEM image. I think `linux-image-oem` and `linux-image-oem-20.04` are worth a try.

Thanks, Lukas! I did some digging and the Ubuntu Wiki has this to say about OEM kernels (https://wiki.ubuntu.com/Kernel/OEMKernel):

> Before the kernel reaches end-of-life, all of the changes made to the OEM kernel will be reviewed to make sure that the kernel in the next Ubuntu release already has the changes it needs.

Currently I have the default kernel: Ubuntu 5.4.0-52.57-generic 5.4.65

Is there reason to assume that 'linux-image-oem-20.04' (currently available as version 5.6.0.1032.28) should have better chances to include any fixes from the 18.04 OEM kernel than, say, 'linux-image-generic-hwe-20.04-edge' (currently version 5.8.0.25.26~20.04.13)?

I think (but I'm not sure this is completely accurate) the OEM kernels contain changes that hadn't been upstreamed yet at the time of their release, whereas the HWE kernels are upstream kernels that are just more recent than the generic kernels.

linux-image-generic-hwe-20.04-edge may actually work well for you as it may contain all the fixes the kernel of the 18.04 OEM image had. I actually use it on my ThinkPad T14.

You may also find this page informative: https://ubuntu.com/kernel/variants.

You can definitely try both, though.

Hi,

Lenovo ThinkPad L390 is certified with 18.04 , enabled with 4.15 oem kernel. It will be upgraded to 5.4 hwe kernel very soon.
The 5.4 in 18.04 (linux-image-generic-hwe-18.04) and 20.04 should including everything you need for L390. We are not expecting that you will have an issue with 20.04.

Please kindly file a bug to launchpad by running this command "ubuntu-bug linux"
Also, the following commands will help us if you are using the latest firmware from Lenovo.
fwupdmgr get-devices
fwupdmgr get-updates

Since my initial report, I tried a few more BIOS options in an attempt to
fix it. I have reset the BIOS with "Load Setup Defaults" after switching
"OS Optimized Defaults" to "Disabled".
I have these settings now:
"UEFI/Legacy Boot": "UEFI Only"
"CSM Support": "Yes"

All of this is guesswork.
Since then, the machine has started successfully four times. But there was
also ...
... one incident where it did not come back from suspend (black screen).
Had to depower (press power button for 10 sec) to restart successfully.
... one incident, after exiting the BIOS with "Exit Saving Changes", where
the machine hung with the aforementioned boot screen with a small "ubuntu"
logo and a turning wheel above it (I incorrectly wrote "below" initially).
Depowering (power button 10 sec) made it boot successfully after that.

On two *earlier* occasions the machine kept hanging even after depowering.
After multiple attempts I finally used the BIOS option "Disable Built-in
Battery", which made it boot successfully again.

For completeness, this is Ubuntu hardware certification page I have been
referring to (Ubuntu on Lenovo ThinkPad L390):
https://certification.ubuntu.com/hardware/201812-26720

I attached a few screenshots of BIOS settings and the boot screen, to avoid
misunderstandings.
I filed a bug with additional information as requested here:
https://bugs.launchpad.net/ubuntu/+bug/1903619

Best Regards
Erwin

On Mon, 9 Nov 2020 at 11:11, Rex Tsai <email address hidden>
wrote:

> Your question #693893 on Ubuntu-Certification changed:
> https://answers.launchpad.net/ubuntu-certification/+question/693893
>
> Status: Open => Needs information
>
> Rex Tsai requested more information:
> Hi,
>
> Lenovo ThinkPad L390 is certified with 18.04 , enabled with 4.15 oem
> kernel. It will be upgraded to 5.4 hwe kernel very soon.
> The 5.4 in 18.04 (linux-image-generic-hwe-18.04) and 20.04 should
> including everything you need for L390. We are not expecting that you will
> have an issue with 20.04.
>
> Please kindly file a bug to launchpad by running this command "ubuntu-bug
> linux"
> Also, the following commands will help us if you are using the latest
> firmware from Lenovo.
> fwupdmgr get-devices
> fwupdmgr get-updates
>
> --
> To answer this request for more information, you can either reply to
> this email or enter your reply at the following page:
> https://answers.launchpad.net/ubuntu-certification/+question/693893
>
> You received this question notification because you asked the question.
>