storage_pool_details overprovisioning settings are being picked up as a tag #2758

Storage

4.12

update configuration name = "storage.overprovisioning.factor" value = 2.0 storageid = [pool.id]

MariaDB [cloud]>  select * from storage_pool_details;
+----+---------+---------------------------------+-------+---------+
| id | pool_id | name                            | value | display |
+----+---------+---------------------------------+-------+---------+
|  2 |       2 | storage.overprovisioning.factor | 2.0   |       1 |
+----+---------+---------------------------------+-------+---------+
1 row in set (0.00 sec)

{errorcode : 431, errortext : u'Target Storage [id=26055c44-abb2-3ec6-8098-3c7f067e6d34] tags [storage.overprovisioning.factor] does not match new disk offering [id=637a5ded-3fba-4eda-9515-fc5218d1c905] tags [null].'}

MariaDB [cloud]>  select * from storage_pool_details;
+----+---------+---------------------------------+-------+---------+
| id | pool_id | name                            | value | display |
+----+---------+---------------------------------+-------+---------+
|  2 |       2 | storage.overprovisioning.factor | 2.0   |       1 |
+----+---------+---------------------------------+-------+---------+
1 row in set (0.00 sec)

MariaDB [cloud]>  select * from storage_pool_tags;
Empty set (0.00 sec)

- Deploy a VM and attach a small disk to it
- with cloudmonkey execute: update configuration name = "storage.overprovisioning.factor" value = 2.0 storageid = [target.pool.id]
- with cloudmonkey execute: migrate volume volumeid=[vol.id] storageid=[target.pool.id] newdiskofferingid=[large.disk.off.id]

I would expect that the volume is migrated with new disk offering

It fails with:
{errorcode : 431, errortext : u'Target Storage [id=26055c44-abb2-3ec6-8098-3c7f067e6d34] tags [storage.overprovisioning.factor] does not match new disk offering [id=637a5ded-3fba-4eda-9515-fc5218d1c905] tags [null].'}

which looks like the overriding overprovisiohnning setting is taken as a tag. Note that there are no tags to the pool or offering at this time that might interfere.