qeth.3ca478 <bus ID of the qeth device>: The HiperSockets device is already a secondary Bridge Port
Explanation
A HiperSockets device cannot be configured as a primary or secondary Bridge Port if it is already configured as a secondary Bridge Port.
User response
None, if you want the device to be a secondary Bridge Port.
If you want to configure the device as the primary Bridge Port,
withdraw the secondary role by writing 'none' to the 'bridgeport_role'
sysfs attribute of the device. Then try again to configure the
device as the primary Bridge Port.