User reports show leaked UE contexts over time, in a scenario where HNB
regularly disconnect and reconnect.
So far, when we receive a HNB REGISTER REQ, we log as "duplicated" and
continue to use the hnb_context unchanged. But it seems obvious that a
HNB that registers does not expect any UE state to remain. It will
obviously not tear down UE contexts (HNBAP or RUA) that have been
established before the HNB REGISTER REQUEST. These hence remain in
osmo-hnbgw indefinitely.
When receiving a HNB REGISTER REQUEST, release all its previous UE
state. Allow the HNB to register with a clean slate.
The aim is to alleviate the observed build-up of apparently orphaned UE
contexts, in order to avoid gradual memory exhaustion.
Related: SYS#6297
Change-Id: I7fa8a04cc3b2dfba263bda5b410961c77fbed332
Neels Hofmeyr
8eefcbee92