Seen on https://gerrit.wikimedia.org/r/#/c/313576/6 and https://gerrit.wikimedia.org/r/#/c/323645/ :
```
09:50:05 INFO:zuul.Cloner:Creating repo mediawiki/core from upstream https://gerrit.wikimedia.org/r/p/mediawiki/core
09:50:06 DEBUG:zuul.Repo:Resetting repository src
09:50:06 DEBUG:zuul.Repo:Updating repository src
09:50:12 Traceback (most recent call last):
09:50:12 File "/usr/bin/zuul-cloner", line 10, in <module>
09:50:12 sys.exit(main())
09:50:12 File "/usr/share/python/zuul/local/lib/python2.7/site-packages/zuul/cmd/cloner.py", line 156, in main
09:50:12 cloner.main()
09:50:12 File "/usr/share/python/zuul/local/lib/python2.7/site-packages/zuul/cmd/cloner.py", line 151, in main
09:50:12 cloner.execute()
09:50:12 File "/usr/share/python/zuul/local/lib/python2.7/site-packages/zuul/lib/cloner.py", line 68, in execute
09:50:12 self.prepareRepo(project, dest)
09:50:12 File "/usr/share/python/zuul/local/lib/python2.7/site-packages/zuul/lib/cloner.py", line 148, in prepareRepo
09:50:12 repo.reset()
09:50:12 File "/usr/share/python/zuul/local/lib/python2.7/site-packages/zuul/merger/merger.py", line 101, in reset
09:50:12 self.update()
09:50:12 File "/usr/share/python/zuul/local/lib/python2.7/site-packages/zuul/merger/merger.py", line 196, in update
09:50:12 origin.update()
09:50:12 File "/usr/share/python/zuul/local/lib/python2.7/site-packages/git/remote.py", line 536, in update
09:50:12 self.repo.git.remote(scmd, self.name, **kwargs)
09:50:12 File "/usr/share/python/zuul/local/lib/python2.7/site-packages/git/cmd.py", line 440, in <lambda>
09:50:12 return lambda *args, **kwargs: self._call_process(name, *args, **kwargs)
09:50:12 File "/usr/share/python/zuul/local/lib/python2.7/site-packages/git/cmd.py", line 834, in _call_process
09:50:12 return self.execute(make_call(), **_kwargs)
09:50:12 File "/usr/share/python/zuul/local/lib/python2.7/site-packages/git/cmd.py", line 627, in execute
09:50:12 raise GitCommandError(command, status, stderr_value)
09:50:12 git.exc.GitCommandError: 'git remote update origin' returned with exit code 1
09:50:12 stderr: 'remote: internal server error
09:50:12 fatal: protocol error: bad pack header
09:50:12 error: Could not fetch origin'
09:50:12 Build step 'Execute shell' marked build as failure
09:50:12 Recording test results
09:50:12 ERROR: Step ‘Publish JUnit test result report’ failed: Test reports were found but none of them are new. Did tests run?
09:50:12 For example, /srv/jenkins-workspace/workspace/mediawiki-extensions-php55/log/junit-phpunit-allexts.xml is 6 hr 12 min old
09:50:12
09:50:12 [PostBuildScript] - Execution post build scripts.
09:50:12 [mediawiki-extensions-php55] $ /bin/bash -xe /tmp/hudson4963821511282952247.sh
09:50:12 + /srv/deployment/integration/slave-scripts/bin/mw-teardown-mysql.sh
09:50:12 ERROR 1269 (HY000) at line 1: Can't revoke all privileges for one or more of the requested users
09:50:12 Build step 'Execute a set of scripts' marked build as failure
09:50:12 Archiving artifacts
09:50:12 Finished: FAILURE
```