Unmanaged datasets destroyed at boot time after import of zpool.cache

[Didier Roche-Tolomelli]

[Impact]
 * People creating manually datasets under the reserved namespace /USERDATA/ were considered good to clean up by ZSys and were removed.
 * Even if this namespace shouldn’t be used by user, mitigate by preventing GC to collect and destroy them.
 * Mark them differently to ZSys user datasets that were untagged so that those last ones are still considered for cleanup
 * This is covered by dedicated use cases.

[Test Case]
 1. zfs create rpool/USERDATA/foo
 2. Run zsysctl service GC
 3. Check that rpool/USERDATA/foo hasn’t been collected.

[Regression Potential]
 * The clean up was too extreme for those edge cases users.
 * GC is a separate, timer-based process and don’t impact boot or other operations.
 * The 30 existing tests on the GC didn’t regress and we now have some additional ones around those use case.

-----

This was reported as https://github.com/ubuntu/zsys/issues/103.

Don’t remove anything that is under /USERDATA/ if this wasn’t a fully zsys unlinked user state (with every other states unlinked as well)

[Launchpad Janitor (janitor)]

This bug was fixed in the package zsys - 0.5.0

---------------
zsys (0.5.0) groovy; urgency=medium

  [ Jean-Baptiste Lallement ]
  [ Didier Roche ]
  * Fix infinite GC loop (LP: #1870461)
  * Enhance timeout handling to avoid error rpc error: code = DeadlineExceeded
    desc = context deadline exceeded while the daemon is doing work
    (LP: #1875564)
  * Stop taking automated or manual snapshot when there is less than 20% of
    free disk space (LP: #1876334)
  * Enable trim support for upgrading users (LP: #1881540)
  * Only clean up previously linked user datasets when unlinked under USERDATA
    (LP: #1881538)
  * Strategy for deleted user datasets via a new hidden command called by
    userdel (LP: #1870058)
  * Get better auto snapshots message when integrated to apt (LP: #1875420)
  * Update LastUsed on shutdown via a new hidden command service call
    (LP: #1881536)
  * Prevent segfault immediately after install when zfs kernel module isn't
    loaded (LP: #1881541)
  * Don’t try to autosave gdm user (and in general non system user), even if
    systemd --user is started for them. (LP: #1881539)
  * Prevent apt printing errors when zsys is removed without purge
    (LP: #1881535)
  * Some tests enhancements:
    - new tests for all the above
    - allow setting a different local socket for debugging/tests purposes only
    - ascii order datasets in golden files
  * Typos and messages fixes. Direct prints are not prefixed with INFO
    anymore.
  * Refreshed po and readme with the above.

 -- Didier Roche <email address hidden> Mon, 01 Jun 2020 09:26:52 +0200

[Timo Aaltonen (tjaalton)]

Hello Didier, or anyone else affected,

Accepted zsys into focal-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/zsys/0.4.6 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.

[Jean-Baptiste Lallement (jibel)]

SRU verification for Focal:
I have reproduced the problem with zsys 0.4.5 in focal and have verified that the version of zsys 0.4.6 in -proposed fixes the issue.

Marking as verification-done

[Launchpad Janitor (janitor)]

This bug was fixed in the package zsys - 0.4.6

---------------
zsys (0.4.6) focal; urgency=medium

  [ Jean-Baptiste Lallement ]
  [ Didier Roche ]
  * Fix infinite GC loop (LP: #1870461)
  * Enhance timeout handling to avoid error rpc error: code = DeadlineExceeded
    desc = context deadline exceeded while the daemon is doing work
    (LP: #1875564)
  * Stop taking automated or manual snapshot when there is less than 20% of
    free disk space (LP: #1876334)
  * Enable trim support for upgrading users (LP: #1881540)
  * Only clean up previously linked user datasets when unlinked under USERDATA
    (LP: #1881538)
  * Strategy for deleted user datasets via a new hidden command called by
    userdel (LP: #1870058)
  * Get better auto snapshots message when integrated to apt (LP: #1875420)
  * Update LastUsed on shutdown via a new hidden command service call
    (LP: #1881536)
  * Prevent segfault immediately after install when zfs kernel module isn't
    loaded (LP: #1881541)
  * Don’t try to autosave gdm user (and in general non system user), even if
    systemd --user is started for them. (LP: #1881539)
  * Prevent apt printing errors when zsys is removed without purge
    (LP: #1881535)
  * Some tests enhancements:
    - new tests for all the above
    - allow setting a different local socket for debugging/tests purposes only
    - ascii order datasets in golden files
  * Typos and messages fixes. Direct prints are not prefixed with INFO
    anymore.
  * Refreshed po and readme with the above.

 -- Didier Roche <email address hidden> Mon, 01 Jun 2020 09:26:52 +0200

[Łukasz Zemczak (sil2100)]

The verification of the Stable Release Update for zsys 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.