subscr: Stop all paging requests if one is failing.

If one paging request is timing out the others will timeout soon
as well. With the current code the next timeout would expire the
next request in the queue. We will now stop all paging requests
and then issue a next paging request. So for both paging success
and failure we will now stop all the other requests.

This is mostly a workaround, one should count on how many
BTSes we are paging and wait for all failures before we remove
the item from the queue.
diff --git a/openbsc/src/gsm_subscriber.c b/openbsc/src/gsm_subscriber.c
index 3e3e74a..1326021 100644
--- a/openbsc/src/gsm_subscriber.c
+++ b/openbsc/src/gsm_subscriber.c
@@ -103,8 +103,19 @@
 	request->cbfn(hooknum, event, msg, data, request->param);
 	subscr->in_callback = 0;
 
-	if (event != GSM_PAGING_SUCCEEDED)
+	if (event != GSM_PAGING_SUCCEEDED) {
+		/*
+		 *  This is a workaround for a bigger issue. We have
+		 *  issued paging that might involve multiple BTSes
+		 *  and one of them have failed now. We will stop the
+		 *  other paging requests as well as the next timeout
+		 *  would work on the next paging request and the queue
+		 *  will do bad things. This should be fixed by counting
+		 *  the outstanding results.
+		 */
+		paging_request_stop(NULL, subscr, NULL, NULL);
 		subscr_put_channel(subscr);
+	}
 
 	subscr_put(subscr);
 	talloc_free(request);
diff --git a/openbsc/tests/channel/channel_test.c b/openbsc/tests/channel/channel_test.c
index a924e5b..a63d8a5 100644
--- a/openbsc/tests/channel/channel_test.c
+++ b/openbsc/tests/channel/channel_test.c
@@ -77,6 +77,7 @@
 void sms_alloc() {}
 void gsm_net_update_ctype(struct gsm_network *network) {}
 void gsm48_secure_channel() {}
+void paging_request_stop() {}
 
 
 struct tlv_definition nm_att_tlvdef;