Exit code 0 during move-back

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May 04 07:24:19 qaserver-04.ci.percona.com Dock2-innobackupex-move[14655]: innobackupex: Creating directory '/pxc/datadir/test'
May 04 07:24:19 qaserver-04.ci.percona.com Dock2-innobackupex-move[14655]: innobackupex: got a fatal error with the following stacktrace: at /usr/bin/innobackupex line 2287.
May 04 07:24:19 qaserver-04.ci.percona.com Dock2-innobackupex-move[14655]: main::process_file('CODE(0x22e2a50)') called at /usr/bin/innobackupex line 2315
May 04 07:24:19 qaserver-04.ci.percona.com Dock2-innobackupex-move[14655]: main::move_file_callback() called at /usr/share/perl5/File/Find.pm line 691
May 04 07:24:19 qaserver-04.ci.percona.com Dock2-innobackupex-move[14655]: File::Find::_find_dir('HASH(0x25a5008)', '/pxc/datadir/.sst', 6) called at /usr/share/perl5/File/Find.pm line 569
May 04 07:24:19 qaserver-04.ci.percona.com Dock2-innobackupex-move[14655]: File::Find::_find_opt('HASH(0x25a5008)', '/pxc/datadir/.sst') called at /usr/share/perl5/File/Find.pm line 1070
May 04 07:24:19 qaserver-04.ci.percona.com Dock2-innobackupex-move[14655]: File::Find::find('CODE(0x22e2f48)', '/pxc/datadir/.sst') called at /usr/bin/innobackupex line 2386
May 04 07:24:19 qaserver-04.ci.percona.com Dock2-innobackupex-move[14655]: main::move_dir_recursively('/pxc/datadir/.sst', '/pxc/datadir', '^(\.\.?|backup-my\.cnf|xtrabackup_logfile|xtrabackup_binary|x...', 0, 1) called at /usr/bin/innobackupex line 2523
May 04 07:24:19 qaserver-04.ci.percona.com Dock2-innobackupex-move[14655]: main::copy_back(1) called at /usr/bin/innobackupex line 1570
May 04 07:24:19 qaserver-04.ci.percona.com Dock2-innobackupex-move[14655]: innobackupex: Error: mkdir failed: Invalid argument at /usr/bin/innobackupex line 2287.
May 04 07:24:19 qaserver-04.ci.percona.com Dock2-wsrep-sst-joiner[14697]: Move successful, removing /pxc/datadir//.sst
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Note that it is exiting with exit status 0 here.