diff options
authorPau Espin Pedrol <pespin@sysmocom.de>2018-11-28 16:47:10 +0100
committerPau Espin Pedrol <pespin@sysmocom.de>2018-12-05 16:06:47 +0000
commit746dbc9fdd05747ce5cc0cb4a94c1db1728053e1 (patch)
parent0ba20df9eee495f5f78f6ff727501b6b39e63d39 (diff)
bsc: Fix lchan iteration for dyn TS during PDCH Deact
In general PDCH channels are not handled as lchans in BSC (lchan_fsm.c), and so when a TS is in ts->pchan_is=GSM_PCHAN_PDCH, no lchan slot is being used. However, during Dynamic TS PDCH Deactivation being in progress (state WAIT_PDCH_DEACT in timeslot_fsm.c), ts->pchan_is =GSM_PCHAN_PDCH, but an lchan slot of that TS is actually already being used by a TCH lchan: it's the one who initiated the deactivate in order to be able to use the TS. While being in WAIT_PDCH_DEACT state and receiving a PDCH DEACT NACK, ts_fsm_error() was called in order to kill the TS and it was expected that it would kill any lchan using it (or willing to start using it). In order to do that, it calls ts_lchans_dispatch() which in turns iterates over all lchans attached to the TS using ts_for_each_lchan(). However, when the NACK arrived we still had ts->pchan_is=GSM_PCHAN_PDCH, ts_for_each_lchan ends up calling ts_as_pchan_for_each_lchan(GSM_PCHAN_PDCH), which in turns calls pchan_subslots(GSM_PCHAN_PDCH) which returns 0, because we don't manage lchans in that mode as explained in first paragraph. This means in this case ts_for_each_lchan() is actually an empty loop while still any of the TCH channels may be in use, and won't be advertised about the TS entering in a broken state. As a result, the lchan won't be released for a while, only after T23001 expires. Related: OS#3708 Change-Id: I9cedb77d6578597f1febab36c54b2ee427c7a4a2
1 files changed, 1 insertions, 1 deletions
diff --git a/src/osmo-bsc/timeslot_fsm.c b/src/osmo-bsc/timeslot_fsm.c
index a39549b54..113ec361c 100644
--- a/src/osmo-bsc/timeslot_fsm.c
+++ b/src/osmo-bsc/timeslot_fsm.c
@@ -123,7 +123,7 @@ static void ts_lchans_dispatch(struct gsm_bts_trx_ts *ts, int lchan_state, uint3
struct gsm_lchan *lchan;
- ts_for_each_lchan(lchan, ts) {
+ ts_for_each_potential_lchan(lchan, ts) {
if (lchan_state >= 0
&& !lchan_state_is(lchan, lchan_state))