zfs-linux FTBFS for riscv64 on Focal

[Heinrich Schuchardt]

[Impact]
 * riscv64 builds fail completely, so users on that architecture can't use ZFS.

[Test Plan]
 * Build zfs-linux on target architecture. No test failure is expected.

[Where problems could occur]
 * Test failures and bugs that are exclusive to RISCV64 might show up

[Other Info]
 * Upstream introduced support riscv64 with 4254e407294b
 * Builds succeed on Jammy and newer, Focal is missing the enablement patch

--
[Original Description]
Building zfs-linux for riscv64 fails on Ubuntu 18.04. There is a single patch missing: https://github.com/openzfs/zfs/commit/4254e407294b211f3399da2ee131b45fe9f4ac80

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "zfs-linux-0.8.3-1ubuntu12.15..0.8.3-1ubuntu12.16.debdiff" 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.]

[Heitor Alves de Siqueira (halves)]

Note that the riscv64 patch is also missing from Focal (20.04), and the package also fails to build there. Upstream included initial support in zfs-2.0.0, so newer Ubuntu releases should have it by default:

$ git describe --contains 4254e407294b211f3399da2ee131b45fe9f4ac80
zfs-2.0.0-rc1~665

[Heinrich Schuchardt (xypron)]

We don't support any RISC-V boards on Bionic.

[Heitor Alves de Siqueira (halves)]

Thank you for the patch, xypron! A few comments on your debdiff:

I don't see the Bug-Ubuntu: tag in the patch, could you please add it so it's DEP-3 compliant?
Looking at the Origin: tag, it's also not clear whether the patch is a clean cherry-pick or needed to be backported with some changes. Could you please add the "upstream" or "backport" tag before the URL there? Thanks!

[Sebastien Bacher (seb128)]

Unsubscribing ubuntu-sponsors, please subscribe them back once the requested changes are made. Also if you want that uploaded to focal the bug description needs to be compliant with what is described on https://wiki.ubuntu.com/StableReleaseUpdates#Procedure

[Heitor Alves de Siqueira (halves)]

Bionic is EoL, if RISC-V support is needed there we'll need to target Pro 18.04.

[Heinrich Schuchardt (xypron)]

I would suggest not to invest in enabling a new feature in Focal now that we have two newer LTS releases. Setting to won't fix.

[Heitor Alves de Siqueira (halves)]

Hi xypron,

thanks for your suggestion. I have this already staged and tested with other fixes for zfs-linux on Focal, so there's little effort involved in it.

On a more broader scope, the patch enabling this only toggles build flags and has no changes to the ZFS source (module and user space). The actual regression risk here should be minimal, considering there are no actual differences in the ZFS source tree besides architectural enablement.

Fixing this build will also make the user space portion of ZFS available on Focal (zfsutils-linux), and this would be especially valuable for the 5.15 HWE kernels where riscv is already supported and enabled in Jammy.

[Timo Aaltonen (tjaalton)]

Hello Heinrich, or anyone else affected,

Accepted zfs-linux into focal-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/zfs-linux/0.8.3-1ubuntu12.18 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, what testing has been performed on the package and change the tag from verification-needed-focal to verification-done-focal. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-focal. 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 for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Heitor Alves de Siqueira (halves)]

I can see this now builds correctly for riscv64, and I was able to install it on a local VM. Basic testing looks good, so I'm marking this one as verified.

[Launchpad Janitor (janitor)]

This bug was fixed in the package zfs-linux - 0.8.3-1ubuntu12.18

---------------
zfs-linux (0.8.3-1ubuntu12.18) focal; urgency=medium

  * Fix riscv64 builds (LP: #2016881)
    - d/p/4940-Preliminary-support-for-RV64G.patch
  * Fix arc_summary not working on HWE 5.15-based kernels (LP: #1980848)
    - d/p/4950-compat-fix-arc_summary-hwe.patch

 -- Heitor Alves de Siqueira <email address hidden> Wed, 10 Apr 2024 16:38:23 +0000

[Andreas Hasenack (ahasenack)]

The verification of the Stable Release Update for zfs-linux has completed successfully and the package is now being 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.