ADT/hint: Multiple DKMS modules fail to build in linux-kvm due to lack of Kconfigs set

[Guilherme G. Piccoli]

This a catch-all Launchpad report regarding the build failures of some DKMS modules (like Nvidia drivers, virtualbox-hwe, ...) in linux-kvm.

The goal of linux-kvm kernel is to be a *very* minimal kernel for virtualized environments (guests), with the bare minimum of Kconfigs enabled, in order to have it booting really fast and with a reduced attack surface. Given that, some DKMS may not work, like virtualbox-hwe (which requires CONFIG_DRM_*).

The objective of this LP is to report such failures and use this information "database" to help us mark Autopackage testing (ADT) failures as _expected_, or else in every kernel cycle we will face the same issues that show up as regressions, when they are in fact incompatibilities between the test and the minimal linux-kvm kernel.

We could use the comments to report individual failures / attach logs.

[Guilherme G. Piccoli (gpiccoli)]

Virtualbox-hwe is expected to fail in linux-kvm, as reported here: https://bugs.launchpad.net/ubuntu/+source/linux-kvm/+bug/1922397

We will hint its ADT test accordingly.

[Guilherme G. Piccoli (gpiccoli)]

Nvidia DKMS drivers fail to build in linux-kvm kernels > 5.8, as reported here:
https://bugs.launchpad.net/ubuntu/+source/linux-kvm/+bug/1922800 .

[Guilherme G. Piccoli (gpiccoli)]

We noticed that recent Nvidia modules (all series, like -450, -460, etc) are failing to build on linux-kvm, due to the lack of CONFIG_PM option, which is not set in linux-kvm. Logs attached for Bionic/Focal.

[Guilherme G. Piccoli (gpiccoli)]

lttng-dkms is also failing to build in Bionic/kvm due to lack of a config option: https://bugs.launchpad.net/ubuntu/+source/lttng-modules/+bug/1905989

[Guilherme G. Piccoli (gpiccoli)]

New one, for hirsute: evdi-dkms fails to build [0].
This is due to t he lack of CONFIG_I2C in such kernel.

I've hinted as NEVER in ADT tests.

[0]
/var/lib/dkms/evdi/1.9.1/build/evdi_i2c.c:49:9: error: implicit declaration of function ‘i2c_add_adapter’; did you mean ‘i2c_verify_adapter’? [-Werror=implicit-function-declaration]
   49 | return i2c_add_adapter(adapter);
      | ^~~~~~~~~~~~~~~
      | i2c_verify_adapter
/var/lib/dkms/evdi/1.9.1/build/evdi_i2c.c: In function ‘evdi_i2c_remove’:
/var/lib/dkms/evdi/1.9.1/build/evdi_i2c.c:54:2: error: implicit declaration of function ‘i2c_del_adapter’; did you mean ‘i2c_verify_adapter’? [-Werror=implicit-function-declaration]