pg_upgrade 9.5 -> 9.6 fails when pg_largeobject is in separate tablespace

Hi.
 
(if this is not the right forum, please point me to it)
 
I have an issue with pg_upgrade upgrading 9.5 to 9.6. (my system is
Ubuntu-16.04 and packages from http://apt.postgresql.org/)
 
In short pg_upgrade fails with:
 
Linking user relation files
No match found in new cluster for old relation with OID 16388 in database
"andreak": "pg_toast.pg_toast_2613" which is the TOAST table for
"pg_catalog.pg_largeobject"
No match found in new cluster for old relation with OID 16390 in database
"andreak": "pg_toast.pg_toast_2613_index" which is an index on
"pg_toast.pg_toast_2613" which is the TOAST table for
"pg_catalog.pg_largeobject"
Failed to match up old and new tables in database "andreak"
Failure, exiting
 
I issued the following command:
PG_NEW_VERSION=9.6
PG_OLD_VERSION=9.5
/usr/lib/postgresql/$PG_NEW_VERSION/bin/pg_upgrade \
          --old-bindir=/usr/lib/postgresql/$PG_OLD_VERSION/bin/ \
          --new-bindir=/usr/lib/postgresql/$PG_NEW_VERSION/bin/ \
          --old-datadir=/var/lib/postgresql/$PG_OLD_VERSION/main \
          --new-datadir=/var/lib/postgresql/$PG_NEW_VERSION/main \
          -o " -c
config_file=/etc/postgresql/$PG_OLD_VERSION/main/postgresql.conf" \
          -O " -c
config_file=/etc/postgresql/$PG_NEW_VERSION/main/postgresql.conf" \
          --link

 
I have pg_largeobject in a separate tablespace, moved by the following command:
psql -U postgres -c "alter table pg_largeobject set tablespace andreak_lo" -d
andreak
 
 
(I've set allow_system_table_mods=on in postgresql.conf)
 
Else I have tablespaces configured outside PGDATA:
mkdir /var/lib/postgresql/9.5/tablespaces/andreak
mkdir /var/lib/postgresql/9.5/tablespaces_lo/andreak
 
These are symlinked:
ln -s /storage/wal/9.5/pg_xlog /var/lib/postgresql/9.5/main/pg_xlog
ln -s /storage/fast_ssd/9.5/tablespaces /var/lib/postgresql/9.5/tablespaces
ln -s /storage/fast_ssd/9.5/tablespaces_lo
/var/lib/postgresql/9.5/tablespaces_lo
 
 
psql -c "create tablespace andreak OWNER andreak location
'/var/lib/postgresql/9.5/tablespaces/andreak'" postgres;
psql -c "create tablespace andreak_lo OWNER andreak location
'/var/lib/postgresql/9.5/tablespaces_lo/andreak'" postgres;
createdb --tablespace=andreak -O andreak andreak
psql -U postgres -c "alter table pg_largeobject set tablespace andreak_lo" -d
andreak

Is this a bug or not a supported configuration by pg_upgraded?
Any hints on how to proceed?
 
Thanks.
 
-- Andreas Joseph Krogh
CTO / Partner - Visena AS
Mobile: +47 909 56 963
andreas(at)visena(dot)com <mailto:andreas(at)visena(dot)com>
www.visena.com <https://www.visena.com>
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