"linux-modules-extra" module missing in pc-kernel snap for 20/track

[Viktor Petersson]

See details here:
https://forum.snapcraft.io/t/enable-kernel-module-for-rtw-8821/27812/6

tl;dr is that the linux-modules-extra module is missing, which is causing WiFi not to work on many amd64 based boards.

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 1954564

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Sergey Borovkov (serge-borovkov)]

We tried building our custom kernel snap that would include this module, unfortunately, this error is encountered since last week when trying to build it.

apt-get download linux-firmware wireless-regdb linux-image-uc20-efi-generic linux-image-5.4.0-97-generic linux-modules-5.4.0-97-generic
E: Unable to locate package linux-image-5.4.0-97-generic
E: Couldn't find any package by glob 'linux-image-5.4.0-97-generic'
E: Couldn't find any package by regex 'linux-image-5.4.0-97-generic'
E: Can't select candidate version from package linux-modules-5.4.0-97-generic as it has no candidate
make: *** [Makefile.efi:33: prepare-kernel] Error 100

Trying previous commits in the repo does not help as well.

KIMGVER=$(apt-cache show linux-image-uc20-efi-generic | sed -n -e 's/^Version: \([^+]*\)\(+.*\)\?/\1/p'|sort -V|tail -1); \
echo "KIMGVER: $KIMGVER"; \
test -n "$KIMGVER" || ( echo "Unable to extract KIMGVER, exit"; false; ); \
if [ "$KIMGVER" != "5.4.0-96.109.1" ]; then \
  echo "Version mismatch:\nInstalled: $KIMGVER Requested: 5.4.0-96.109.1"; \
  false; \
fi
KIMGVER: 5.4.0-97.110.1
Version mismatch:
Installed: 5.4.0-97.110.1 Requested: 5.4.0-96.109.1
make: *** [Makefile.efi:53: version-check] Error 1
Failed to build 'kernel'.

[Renat (renat.galimov)]

We've successfully built the kernel snap with the rtl8821ce-5.5.2.1 module.
I can confirm that it boots loads and enables the WiFi interface. I disabled Secure Boot to make it work.

The problem is in Secure Boot, it doesn't allow us to load the module when enabled.

Is there any chance that this module will be included in the focal pre-built modules, so we don't need to build it with dkms?

[Ondrej Kubik (ondrak)]

OK this would mean that kernel modules in the linux-modules-extra packages are not signed.
kernel enforces kernel module signature check if SB is enabled.
But our modules should be signed.
@Renat, can you confirm exact versions of all the stage packages?
As those need to be aligned for signing keys to match.
Cheers
Ondra

[Renat (renat.galimov)]

Ondrej, I built the module using rtl8821ce-dkms package.

This is how I built the kernel snap: https://paste.ubuntu.com/p/4KzY8qM6gm/