lttng-modules-dkms failed to build with 4.14 Azure edge kernel on Xenial

[Po-Hsu Lin]

SRU request, Xenial, Artful

[Impact]

lttng dkms modules fail to build against newer HWE kernels because of missing 4.14 compat fixes that allow it to build against newer 4.14 kernels.

[Fix]
Upstream lttng 4.14 compat fixes.

[Testcase]
Without the fix, running the kernel team autotest lttng regression test suite fails because the module does not build and install. With the fix the lttng smoke tests pass.

To run the test:
sudo autotest/client/autotest-local autotest/client/tests/ubuntu_lttng_smoke_test/control

using git://kernel.ubuntu.com/ubuntu/autotest and
git://kernel.ubuntu.com/ubuntu/autotest-client-tests

[Regression Potential]
lttng fails to build and work against older kernels. As the new code is #if'def'd compat code the 4.14 specific changes are not built into the older kernels, so this risk is small.

--------------------------------------------------------------------------

[stdout] Setting up lttng-modules-dkms (2.8.0-1ubuntu1~16.04.3) ...
 [stdout] Loading new lttng-modules-2.8.0 DKMS files...
 [stdout] First Installation: checking all kernels...
 [stdout] Building only for 4.14.0-1002-azure-edge
 [stdout] Building initial module for 4.14.0-1002-azure-edge
 [stdout] Error! Bad return status for module build on kernel: 4.14.0-1002-azure-edge (x86_64)
 [stdout] Consult /var/lib/dkms/lttng-modules/2.8.0/build/make.log for more information.

[Po-Hsu Lin (cypressyew)]

lttng dkms module build log (/var/lib/dkms/lttng-modules/2.8.0/build/make.log)

http://paste.ubuntu.com/26345778/

[Colin Ian King (colin-king)]

Would you mind testing the fixed dkms lttng modules from ppa:colin-king/lttng-4.14-compat and let me know if the extra compat changes fix things?

Colin

[Po-Hsu Lin (cypressyew)]

Sure,

Since azure kernel is now being tested, I will need to wait until it finishes to get started.

[Colin Ian King (colin-king)]

Any feedback on these results?

[Po-Hsu Lin (cypressyew)]

No, sorry
those azure nodes are sharing the same test pool, as the kernel was re-spinning (last respin on Feb. 2), it's not that easy to grab a gap for testing.
I will keep an eye on this.
Thanks.

[Po-Hsu Lin (cypressyew)]

Hi Colin,
I have encountered a build issue with the proposed 4.14 Azure edge kernel.
log: http://paste.ubuntu.com/26528041/

[Colin Ian King (colin-king)]

Ahah, seems like we also need upstream commits for the Azure kernel to build:

     0032-Update-kvm-instrumentation-for-4.15.patch
     0033-Fix-kvm-instrumentation-for-4.15.patch
     0034-Update-kvm-instrumentation-for-3.16.52-and-3.2.97.patch
     0035-Update-kvm-instrumentation-for-debian-kernel-4.9.65-.patch
     0036-Update-kvm-instrumentation-for-4.14.14-4.9.77-4.4.11.patch

I've uploaded a test package into a new PPA ppa:colin-king/lttng-4.14-azure - do you mind re-testing with this updated package?

Thanks. Colin.

[Po-Hsu Lin (cypressyew)]

The module was built correctly.
And all tests have passed in lttng test suite.
Thanks!

[Chris J Arges (arges)]

Hello Po-Hsu, or anyone else affected,

Accepted lttng-modules into artful-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/lttng-modules/2.9.0-1ubuntu3.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed.Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested and change the tag from verification-needed-artful to verification-done-artful. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-artful. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Chris J Arges (arges)]

Hello Po-Hsu, or anyone else affected,

Accepted lttng-modules into xenial-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/lttng-modules/2.8.0-1ubuntu1~16.04.4 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed.Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested and change the tag from verification-needed-xenial to verification-done-xenial. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-xenial. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Colin Ian King (colin-king)]

@Po-Hsu, do you mind testing this on an Azure instance as I don't have access to one.

[Po-Hsu Lin (cypressyew)]

The lttng module could be built on azure edge kernel now.
Thanks!

[Łukasz Zemczak (sil2100)]

The bionic bug is marked as 'Incomplete' - what does that mean?

[Brian Murray (brian-murray)]

@colin-king - Is there something we, the SRU team, should be watching for to know when this is fixed in Bionic?

[Colin Ian King (colin-king)]

Brian, the 2.10.5-1 version in Bionic supports the required compat fixes already, so no fix was required.

[Launchpad Janitor (janitor)]

This bug was fixed in the package lttng-modules - 2.9.0-1ubuntu3.1

---------------
lttng-modules (2.9.0-1ubuntu3.1) artful; urgency=medium

  * Fix builds for 4.14 kernel (LP: #1739591)
    - [7ceeb15] Fix: update writeback instrumentation for kernel 4.14
    - [1f1ec4e] Fix: update btrfs instrumentation for kernel 4.14
    - [da3122a] Fix: version check error in btrfs instrumentation
    - [7feabe5] Fix: update block instrumentation for 4.14 kernel
    - [467f3a4] Fix: lttng-logger get_user_pages_fast error handling
    - [1d822c6] Update: kvm instrumentation for 4.14.14+, 4.9.77+, 4.4.112+
    - [bda29b7] Update kvm instrumentation for debian kernel 4.9.65-3
    - [5ccd696] Update: kvm instrumentation for 3.16.52 and 3.2.97
    - [d9f561b] Fix: kvm instrumentation for 4.15
    - [3363052] Update kvm instrumentation for 4.15

 -- Colin Ian King <email address hidden> Tue, 6 Feb 2018 16:02:03 +0000

[Łukasz Zemczak (sil2100)]

The verification of the Stable Release Update for lttng-modules has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

[Launchpad Janitor (janitor)]

This bug was fixed in the package lttng-modules - 2.8.0-1ubuntu1~16.04.4

---------------
lttng-modules (2.8.0-1ubuntu1~16.04.4) xenial; urgency=medium

  * Fix builds on HWE 4.14 kernel (LP: #1739591)
    Apply the following upstream commits:
     0030-Fix-update-block-instrumentation-for-4.14-kernel.patch
     0031-Fix-update-writeback-instrumentation-for-kernel-4.14.patch
     0032-Update-kvm-instrumentation-for-4.15.patch
     0033-Fix-kvm-instrumentation-for-4.15.patch
     0034-Update-kvm-instrumentation-for-3.16.52-and-3.2.97.patch
     0035-Update-kvm-instrumentation-for-debian-kernel-4.9.65-.patch
     0036-Update-kvm-instrumentation-for-4.14.14-4.9.77-4.4.11.patch

 -- Colin Ian King <email address hidden> Tue, 6 Feb 2018 10:38:22 +0000