xtrx-dkms module should not try to build when CONFIG_PPS is disabled

[Roxana Nicolescu]

SRU justification:

[Impact]

This is encountered on linux kernel derivatives with fewer configuration options enabled.
First time seen on jammy:linux-kvm-1029.

During build, it fails with the following error:
...
make -j1 KERNELRELEASE=5.15.0-1030-kvm -C /lib/modules/5.15.0-1030-kvm/build M=/var/lib/dkms/xtrx/0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.1/build...(bad exit status: 2)
Error! Bad return status for module build on kernel: 5.15.0-1030-kvm (x86_64)
Consult /var/lib/dkms/xtrx/0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.1/build/make.log for more information.
E: xtrx/0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.1 failed to build for 5.15.0-1030-kvm
========== /var/lib/dkms/xtrx/0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.1/build/make.log ==========
DKMS make.log for xtrx-0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.1 for kernel 5.15.0-1030-kvm (x86_64)
Thu Mar 9 00:04:53 UTC 2023
make: Entering directory '/usr/src/linux-headers-5.15.0-1030-kvm'
  CC [M] /var/lib/dkms/xtrx/0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.1/build/xtrx.o
  MODPOST /var/lib/dkms/xtrx/0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.1/build/Module.symvers
ERROR: modpost: "pps_register_source" [/var/lib/dkms/xtrx/0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.1/build/xtrx.ko] undefined!
ERROR: modpost: "pps_event" [/var/lib/dkms/xtrx/0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.1/build/xtrx.ko] undefined!
ERROR: modpost: "pps_unregister_source" [/var/lib/dkms/xtrx/0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.1/build/xtrx.ko] undefined!
make[1]: *** [scripts/Makefile.modpost:133: /var/lib/dkms/xtrx/0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.1/build/Module.symvers] Error 1
make[1]: *** Deleting file '/var/lib/dkms/xtrx/0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.1/build/Module.symvers'
make: *** [Makefile:1821: modules] Error 2
make: Leaving directory '/usr/src/linux-headers-5.15.0-1030-kvm

because CONFIG_PPS=n

[Fix]
Add a rule to avoid building xtrx-dkms when CONFIG_PPS=n

[Test Plan]
Install a new version of jammy:linux-kvm (1029 for example).
apt install xtrx-dkms will fail as described above.
After the fix, it will not be built at all.

Once the package is in proposed, a new adt is triggered against proposed for jammy:linux-kvm.

[Where problems could occur]
Low possibility of new issues.

[Note]
This fix is not scalable in the sense that if configuration name changes, the module has to be changed as well.

[Roxana Nicolescu (roxanan)]

Proposed fix is attached.

I put the rule in debian/dkms file, not in dkms.conf. dkms.conf is overridden by dkms file I noticed and the change has no affect.

tested on linux-kvm-1029

ubuntu@jammy-kvm:~/xtrx$ sudo dpkg -i xtrx-dkms_0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.2_all.deb
(Reading database ... 142334 files and directories currently installed.)
Preparing to unpack xtrx-dkms_0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.2_all.deb ...
Deleting module xtrx-0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.2 completely from the DKMS tree.
Unpacking xtrx-dkms (0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.2) over (0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.2) ...
Setting up xtrx-dkms (0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.2) ...
Loading new xtrx-0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.2 DKMS files...
Building for 5.15.0-1029-kvm
Building initial module for 5.15.0-1029-kvm
Error! The /var/lib/dkms/xtrx/0.0.1+git20190320.5ae3a3e-3ubuntu1~22.04.2/5.15.0-1029-kvm/x86_64/dkms.conf for module xtrx includes a BUILD_EXCLUSIVE directive which does not match this kernel/arch.
This indicates that it should not be built.
Skipped.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "xtrx.patch" seems to be a debdiff. The ubuntu-sponsors team has been subscribed to the bug report so that they can review and hopefully sponsor the debdiff. If the attachment isn't a patch, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are member of the ~ubuntu-sponsors, unsubscribe the team.

[This is an automated message performed by a Launchpad user owned by ~brian-murray, for any issue please contact him.]

[Dimitri John Ledkov (xnox)]

this patch is incorrect.

BUILD_EXCLUSIVE_KERNEL greps on kernel abi version / stamp.

I think you want to use BUILD_EXCLUSIVE_CONFIG option here instead, which is a patch applied in ubuntu/debian & upstream.

We had to fix this up somewhere else already, so it seems like a persistent copy & past bug from the patches prepared around that time. Please fix this up.

[Simon Chopin (schopin)]

Hi,
Marking this as Incomplete until the patch worked on to be in an uploadable state. Unless the Kernel team would like to handle this internally?

[Benjamin Drung (bdrung)]

I unsubscribed ~ubuntu-sponsors. Please resubscribe ~ubuntu-sponsors once the patch is ready for upload.

[Launchpad Janitor (janitor)]

[Expired for xtrx-dkms (Ubuntu) because there has been no activity for 60 days.]

[Launchpad Janitor (janitor)]

[Expired for xtrx-dkms (Ubuntu Jammy) because there has been no activity for 60 days.]