diff --git a/src/libvlr/vlr_lu_fsm.c b/src/libvlr/vlr_lu_fsm.c
new file mode 100644
index 0000000..d32659f
--- /dev/null
+++ b/src/libvlr/vlr_lu_fsm.c
@@ -0,0 +1,1424 @@
+/* Osmocom Visitor Location Register (VLR): Location Update FSMs */
+
+/* (C) 2016 by Harald Welte <laforge@gnumonks.org>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <osmocom/core/fsm.h>
+#include <osmocom/gsm/gsup.h>
+#include <openbsc/vlr.h>
+#include <openbsc/debug.h>
+
+#include "vlr_core.h"
+#include "vlr_auth_fsm.h"
+#include "vlr_lu_fsm.h"
+
+#define S(x)	(1 << (x))
+
+#define LU_TIMEOUT_LONG		30
+
+enum vlr_fsm_result {
+	VLR_FSM_RESULT_NONE,
+	VLR_FSM_RESULT_SUCCESS,
+	VLR_FSM_RESULT_FAILURE,
+};
+
+
+/***********************************************************************
+ * Update_HLR_VLR, TS 23.012 Chapter 4.1.2.4
+ ***********************************************************************/
+
+enum upd_hlr_vlr_state {
+	UPD_HLR_VLR_S_INIT,
+	UPD_HLR_VLR_S_WAIT_FOR_DATA,
+	UPD_HLR_VLR_S_DONE,
+};
+
+enum upd_hlr_vlr_evt {
+	UPD_HLR_VLR_E_START,
+	UPD_HLR_VLR_E_INS_SUB_DATA,
+	UPD_HLR_VLR_E_ACT_TRACE_MODE,
+	UPD_HLR_VLR_E_FW_CHECK_SS_IND,
+	UPD_HLR_VLR_E_UPD_LOC_ACK,
+	UPD_HLR_VLR_E_UPD_LOC_NACK,
+};
+
+static const struct value_string upd_hlr_vlr_event_names[] = {
+	OSMO_VALUE_STRING(UPD_HLR_VLR_E_START),
+	OSMO_VALUE_STRING(UPD_HLR_VLR_E_INS_SUB_DATA),
+	OSMO_VALUE_STRING(UPD_HLR_VLR_E_ACT_TRACE_MODE),
+	OSMO_VALUE_STRING(UPD_HLR_VLR_E_FW_CHECK_SS_IND),
+	OSMO_VALUE_STRING(UPD_HLR_VLR_E_UPD_LOC_ACK),
+	OSMO_VALUE_STRING(UPD_HLR_VLR_E_UPD_LOC_NACK),
+	{ 0, NULL }
+};
+
+static void upd_hlr_vlr_fsm_init(struct osmo_fsm_inst *fi, uint32_t event,
+				 void *data)
+{
+	struct vlr_subscr *vsub = fi->priv;
+
+	OSMO_ASSERT(event == UPD_HLR_VLR_E_START);
+
+	/* Send UpdateLocation to HLR */
+	vlr_subscr_req_lu(vsub, vsub->vlr->cfg.is_ps);
+	osmo_fsm_inst_state_chg(fi, UPD_HLR_VLR_S_WAIT_FOR_DATA,
+				LU_TIMEOUT_LONG, 0);
+}
+
+static void upd_hlr_vlr_fsm_wait_data(struct osmo_fsm_inst *fi, uint32_t event,
+				      void *data)
+{
+	struct vlr_subscr *vsub = fi->priv;
+
+	switch (event) {
+	case UPD_HLR_VLR_E_INS_SUB_DATA:
+		/* FIXME: Insert_Subscr_Data_VLR */
+		break;
+	case UPD_HLR_VLR_E_ACT_TRACE_MODE:
+		/* TODO: Activate_Tracing_VLR */
+		break;
+	case UPD_HLR_VLR_E_FW_CHECK_SS_IND:
+		/* TODO: Forward Check SS Ind to MSC */
+		break;
+	case UPD_HLR_VLR_E_UPD_LOC_ACK:
+		/* Inside Update_HLR_VLR after UpdateLocationAck */
+		vsub->sub_dataconf_by_hlr_ind = true;
+		vsub->loc_conf_in_hlr_ind = true;
+		osmo_fsm_inst_state_chg(fi, UPD_HLR_VLR_S_DONE, 0, 0);
+		osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, NULL);
+		break;
+	case UPD_HLR_VLR_E_UPD_LOC_NACK:
+		/* Inside Update_HLR_VLR after UpdateLocationNack */
+		/* TODO: Check_User_Error_In_Serving_Network_Entity */
+		vsub->sub_dataconf_by_hlr_ind = false;
+		vsub->loc_conf_in_hlr_ind = false;
+		osmo_fsm_inst_state_chg(fi, UPD_HLR_VLR_S_DONE, 0, 0);
+		/* Data is a pointer to a gsm48_gmm_cause which we
+		 * simply pass through */
+		osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, data);
+		break;
+	}
+}
+
+static const struct osmo_fsm_state upd_hlr_vlr_states[] = {
+	[UPD_HLR_VLR_S_INIT] = {
+		.in_event_mask = S(UPD_HLR_VLR_E_START),
+		.out_state_mask = S(UPD_HLR_VLR_S_WAIT_FOR_DATA),
+		.name = OSMO_STRINGIFY(UPD_HLR_VLR_S_INIT),
+		.action = upd_hlr_vlr_fsm_init,
+	},
+	[UPD_HLR_VLR_S_WAIT_FOR_DATA] = {
+		.in_event_mask = S(UPD_HLR_VLR_E_INS_SUB_DATA) |
+				 S(UPD_HLR_VLR_E_ACT_TRACE_MODE) |
+				 S(UPD_HLR_VLR_E_FW_CHECK_SS_IND) |
+				 S(UPD_HLR_VLR_E_UPD_LOC_ACK) |
+				 S(UPD_HLR_VLR_E_UPD_LOC_NACK),
+		.out_state_mask = S(UPD_HLR_VLR_S_DONE),
+		.name = OSMO_STRINGIFY(UPD_HLR_VLR_S_WAIT_FOR_DATA),
+		.action = upd_hlr_vlr_fsm_wait_data,
+	},
+	[UPD_HLR_VLR_S_DONE] = {
+		.name = OSMO_STRINGIFY(UPD_HLR_VLR_S_DONE),
+	},
+};
+
+static struct osmo_fsm upd_hlr_vlr_fsm = {
+	.name = "upd_hlr_vlr_fsm",
+	.states = upd_hlr_vlr_states,
+	.num_states = ARRAY_SIZE(upd_hlr_vlr_states),
+	.allstate_event_mask = 0,
+	.allstate_action = NULL,
+	.log_subsys = DVLR,
+	.event_names = upd_hlr_vlr_event_names,
+};
+
+struct osmo_fsm_inst *
+upd_hlr_vlr_proc_start(struct osmo_fsm_inst *parent,
+		       struct vlr_subscr *vsub,
+		       uint32_t parent_event)
+{
+	struct osmo_fsm_inst *fi;
+
+	fi = osmo_fsm_inst_alloc_child(&upd_hlr_vlr_fsm, parent,
+					parent_event);
+	if (!fi)
+		return NULL;
+
+	fi->priv = vsub;
+	osmo_fsm_inst_dispatch(fi, UPD_HLR_VLR_E_START, NULL);
+
+	return fi;
+}
+
+
+/***********************************************************************
+ * Subscriber_Present_VLR, TS 29.002 Chapter 25.10.1
+ ***********************************************************************/
+
+enum sub_pres_vlr_state {
+	SUB_PRES_VLR_S_INIT,
+	SUB_PRES_VLR_S_WAIT_FOR_HLR,
+	SUB_PRES_VLR_S_DONE,
+};
+
+enum sub_pres_vlr_event {
+	SUB_PRES_VLR_E_START,
+	SUB_PRES_VLR_E_READY_SM_CNF,
+	SUB_PRES_VLR_E_READY_SM_ERR,
+};
+
+static const struct value_string sub_pres_vlr_event_names[] = {
+	OSMO_VALUE_STRING(SUB_PRES_VLR_E_START),
+	OSMO_VALUE_STRING(SUB_PRES_VLR_E_READY_SM_CNF),
+	OSMO_VALUE_STRING(SUB_PRES_VLR_E_READY_SM_ERR),
+	{ 0, NULL }
+};
+
+static void sub_pres_vlr_fsm_init(struct osmo_fsm_inst *fi, uint32_t event,
+				  void *data)
+{
+	struct vlr_subscr *vsub = fi->priv;
+	OSMO_ASSERT(event == SUB_PRES_VLR_E_START);
+
+	if (!vsub->ms_not_reachable_flag) {
+		osmo_fsm_inst_state_chg(fi, SUB_PRES_VLR_S_DONE, 0, 0);
+		osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, NULL);
+		return;
+	}
+	/* FIXME: Send READY_FOR_SM via GSUP */
+	osmo_fsm_inst_state_chg(fi, SUB_PRES_VLR_S_WAIT_FOR_HLR,
+				LU_TIMEOUT_LONG, 0);
+}
+
+static void sub_pres_vlr_fsm_wait_hlr(struct osmo_fsm_inst *fi, uint32_t event,
+				      void *data)
+{
+	struct vlr_subscr *vsub = fi->priv;
+
+	switch (event) {
+	case SUB_PRES_VLR_E_READY_SM_CNF:
+		vsub->ms_not_reachable_flag = false;
+		break;
+	case SUB_PRES_VLR_E_READY_SM_ERR:
+		break;
+	}
+	osmo_fsm_inst_state_chg(fi, SUB_PRES_VLR_S_DONE, 0, 0);
+	osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, NULL);
+}
+
+static const struct osmo_fsm_state sub_pres_vlr_states[] = {
+	[SUB_PRES_VLR_S_INIT] = {
+		.in_event_mask = S(SUB_PRES_VLR_E_START),
+		.out_state_mask = S(SUB_PRES_VLR_S_WAIT_FOR_HLR) |
+				  S(SUB_PRES_VLR_S_DONE),
+		.name = OSMO_STRINGIFY(SUB_PRES_VLR_S_INIT),
+		.action = sub_pres_vlr_fsm_init,
+	},
+	[SUB_PRES_VLR_S_WAIT_FOR_HLR] = {
+		.in_event_mask = S(SUB_PRES_VLR_E_READY_SM_CNF) |
+				 S(SUB_PRES_VLR_E_READY_SM_ERR),
+		.out_state_mask = S(SUB_PRES_VLR_S_DONE),
+		.name = OSMO_STRINGIFY(SUB_PRES_VLR_S_WAIT_FOR_HLR),
+		.action = sub_pres_vlr_fsm_wait_hlr,
+	},
+	[SUB_PRES_VLR_S_DONE] = {
+		.name = OSMO_STRINGIFY(SUB_PRES_VLR_S_DONE),
+	},
+};
+
+static struct osmo_fsm sub_pres_vlr_fsm = {
+	.name = "sub_pres_vlr_fsm",
+	.states = sub_pres_vlr_states,
+	.num_states = ARRAY_SIZE(sub_pres_vlr_states),
+	.allstate_event_mask = 0,
+	.allstate_action = NULL,
+	.log_subsys = DVLR,
+	.event_names = sub_pres_vlr_event_names,
+};
+
+struct osmo_fsm_inst *sub_pres_vlr_fsm_start(struct osmo_fsm_inst *parent,
+					     struct vlr_subscr *vsub,
+					     uint32_t term_event)
+{
+	struct osmo_fsm_inst *fi;
+
+	fi = osmo_fsm_inst_alloc_child(&sub_pres_vlr_fsm, parent,
+					term_event);
+	if (!fi)
+		return NULL;
+
+	fi->priv = vsub;
+	osmo_fsm_inst_dispatch(fi, SUB_PRES_VLR_E_START, NULL);
+
+	return fi;
+}
+
+/***********************************************************************
+ * Location_Update_Completion_VLR, TS 23.012 Chapter 4.1.2.3
+ ***********************************************************************/
+
+enum lu_compl_vlr_state {
+	LU_COMPL_VLR_S_INIT,
+	LU_COMPL_VLR_S_WAIT_SUB_PRES,
+	LU_COMPL_VLR_S_WAIT_IMEI,
+	LU_COMPL_VLR_S_WAIT_IMEI_TMSI,
+	LU_COMPL_VLR_S_WAIT_TMSI_CNF,
+	LU_COMPL_VLR_S_DONE,
+};
+
+enum lu_compl_vlr_event {
+	LU_COMPL_VLR_E_START,
+	LU_COMPL_VLR_E_SUB_PRES_COMPL,
+	LU_COMPL_VLR_E_IMEI_CHECK_ACK,
+	LU_COMPL_VLR_E_IMEI_CHECK_NACK,
+	LU_COMPL_VLR_E_NEW_TMSI_ACK,
+};
+
+static const struct value_string lu_compl_vlr_event_names[] = {
+	OSMO_VALUE_STRING(LU_COMPL_VLR_E_START),
+	OSMO_VALUE_STRING(LU_COMPL_VLR_E_SUB_PRES_COMPL),
+	OSMO_VALUE_STRING(LU_COMPL_VLR_E_IMEI_CHECK_ACK),
+	OSMO_VALUE_STRING(LU_COMPL_VLR_E_IMEI_CHECK_NACK),
+	OSMO_VALUE_STRING(LU_COMPL_VLR_E_NEW_TMSI_ACK),
+	{ 0, NULL }
+};
+
+struct lu_compl_vlr_priv {
+	struct vlr_subscr *vsub;
+	void *msc_conn_ref;
+	struct osmo_fsm_inst *sub_pres_vlr_fsm;
+	uint32_t parent_event_success;
+	uint32_t parent_event_failure;
+	void *parent_event_data;
+	enum vlr_fsm_result result;
+	uint8_t cause;
+	bool assign_tmsi;
+};
+
+static void _vlr_lu_compl_fsm_done(struct osmo_fsm_inst *fi,
+				   enum vlr_fsm_result result,
+				   uint8_t cause)
+{
+	struct lu_compl_vlr_priv *lcvp = fi->priv;
+	lcvp->result = result;
+	lcvp->cause = cause;
+	osmo_fsm_inst_state_chg(fi, LU_COMPL_VLR_S_DONE, 0, 0);
+}
+
+static void vlr_lu_compl_fsm_success(struct osmo_fsm_inst *fi)
+{
+	struct lu_compl_vlr_priv *lcvp = fi->priv;
+	struct vlr_subscr *vsub = lcvp->vsub;
+	if (!vsub->lu_complete) {
+		vsub->lu_complete = true;
+		/* Balanced by vlr_subscr_rx_imsi_detach() */
+		vlr_subscr_get(vsub);
+	}
+	_vlr_lu_compl_fsm_done(fi, VLR_FSM_RESULT_SUCCESS, 0);
+}
+
+static void vlr_lu_compl_fsm_failure(struct osmo_fsm_inst *fi, uint8_t cause)
+{
+	struct lu_compl_vlr_priv *lcvp = fi->priv;
+	lcvp->vsub->vlr->ops.tx_lu_rej(lcvp->msc_conn_ref, cause);
+	_vlr_lu_compl_fsm_done(fi, VLR_FSM_RESULT_FAILURE, cause);
+}
+
+static void vlr_lu_compl_fsm_dispatch_result(struct osmo_fsm_inst *fi,
+					     uint32_t prev_state)
+{
+	struct lu_compl_vlr_priv *lcvp = fi->priv;
+	if (!fi->proc.parent) {
+		LOGPFSML(fi, LOGL_ERROR, "No parent FSM\n");
+		return;
+	}
+	osmo_fsm_inst_dispatch(fi->proc.parent,
+			       (lcvp->result == VLR_FSM_RESULT_SUCCESS)
+			       ? lcvp->parent_event_success
+			       : lcvp->parent_event_failure,
+			       &lcvp->cause);
+}
+
+static void lu_compl_vlr_init(struct osmo_fsm_inst *fi, uint32_t event,
+			      void *data)
+{
+	struct lu_compl_vlr_priv *lcvp = fi->priv;
+	struct vlr_subscr *vsub = lcvp->vsub;
+	struct vlr_instance *vlr;
+	OSMO_ASSERT(vsub);
+	vlr = vsub->vlr;
+	OSMO_ASSERT(vlr);
+
+	OSMO_ASSERT(event == LU_COMPL_VLR_E_START);
+
+	/* TODO: National Roaming restrictions? */
+	/* TODO: Roaming restriction due to unsupported feature in subscriber
+	 * data? */
+	/* TODO: Regional subscription restriction? */
+	/* TODO: Administrative restriction of subscribres' access feature? */
+	/* TODO: AccessRestrictuionData parameter available? */
+	/* TODO: AccessRestrictionData permits RAT? */
+	/* Node 1 */
+	/* TODO: Autonomous CSG supported in VPLMN and allowed by HPLMN? */
+	/* TODO: Hybrid Cel / CSG Cell */
+	/* Node 2 */
+	vsub->la_allowed = true;
+	vsub->imsi_detached_flag = false;
+	/* Start Subscriber_Present_VLR Procedure */
+	osmo_fsm_inst_state_chg(fi, LU_COMPL_VLR_S_WAIT_SUB_PRES,
+				LU_TIMEOUT_LONG, 0);
+
+	lcvp->sub_pres_vlr_fsm = sub_pres_vlr_fsm_start(fi, vsub,
+						LU_COMPL_VLR_E_SUB_PRES_COMPL);
+
+}
+
+static void lu_compl_vlr_new_tmsi(struct osmo_fsm_inst *fi)
+{
+	struct lu_compl_vlr_priv *lcvp = fi->priv;
+	struct vlr_subscr *vsub = lcvp->vsub;
+	struct vlr_instance *vlr = vsub->vlr;
+
+	LOGPFSM(fi, "%s()\n", __func__);
+
+	if (vlr_subscr_alloc_tmsi(vsub)) {
+		vlr_lu_compl_fsm_failure(fi,
+					 GSM48_REJECT_SRV_OPT_TMP_OUT_OF_ORDER);
+		return;
+	}
+
+	osmo_fsm_inst_state_chg(fi, LU_COMPL_VLR_S_WAIT_TMSI_CNF,
+				vlr_timer(vlr, 3250), 3250);
+
+	vlr->ops.tx_lu_acc(lcvp->msc_conn_ref, vsub->tmsi_new);
+}
+
+/* After completion of Subscriber_Present_VLR */
+static void lu_compl_vlr_wait_subscr_pres(struct osmo_fsm_inst *fi,
+					  uint32_t event,
+					  void *data)
+{
+	struct lu_compl_vlr_priv *lcvp = fi->priv;
+	struct vlr_subscr *vsub = lcvp->vsub;
+	struct vlr_instance *vlr = vsub->vlr;
+
+	OSMO_ASSERT(event == LU_COMPL_VLR_E_SUB_PRES_COMPL);
+
+	lcvp->sub_pres_vlr_fsm = NULL;
+
+	/* TODO: Trace_Subscriber_Activity_VLR */
+
+	if (vlr->cfg.check_imei_rqd) {
+		/* Check IMEI VLR */
+		osmo_fsm_inst_state_chg(fi,
+					lcvp->assign_tmsi ?
+					  LU_COMPL_VLR_S_WAIT_IMEI_TMSI
+					: LU_COMPL_VLR_S_WAIT_IMEI,
+					vlr_timer(vlr, 3270), 3270);
+		vlr->ops.tx_id_req(lcvp->msc_conn_ref, GSM_MI_TYPE_IMEI);
+		return;
+	}
+
+	/* Do we need to allocate a TMSI? */
+	if (lcvp->assign_tmsi) {
+		lu_compl_vlr_new_tmsi(fi);
+		return;
+	}
+
+	/* Location Updating Accept */
+	vlr->ops.tx_lu_acc(lcvp->msc_conn_ref, GSM_RESERVED_TMSI);
+	vlr_lu_compl_fsm_success(fi);
+}
+
+/* Waiting for completion of CHECK_IMEI_VLR */
+static void lu_compl_vlr_wait_imei(struct osmo_fsm_inst *fi, uint32_t event,
+				   void *data)
+{
+	struct lu_compl_vlr_priv *lcvp = fi->priv;
+	struct vlr_subscr *vsub = lcvp->vsub;
+	struct vlr_instance *vlr = vsub->vlr;
+
+	switch (event) {
+	case LU_COMPL_VLR_E_IMEI_CHECK_ACK:
+		if (!vsub->imei[0]) {
+			/* Abort: Do nothing */
+			vlr_lu_compl_fsm_failure(fi,
+						 GSM48_REJECT_PROTOCOL_ERROR);
+			return;
+		}
+		/* Pass */
+		break;
+
+	case LU_COMPL_VLR_E_IMEI_CHECK_NACK:
+		vlr_lu_compl_fsm_failure(fi, GSM48_REJECT_ILLEGAL_ME);
+		/* FIXME: IMEI Check Fail to VLR Application (Detach IMSI VLR) */
+		return;
+	}
+
+	/* IMEI is available. Allocate TMSI if needed. */
+	if (lcvp->assign_tmsi) {
+		if (fi->state != LU_COMPL_VLR_S_WAIT_IMEI_TMSI)
+			LOGPFSML(fi, LOGL_ERROR,
+				 "TMSI required, expected to be in state"
+				 " LU_COMPL_VLR_S_WAIT_IMEI_TMSI,"
+				 " am in %s instead\n",
+				 osmo_fsm_state_name(fi->fsm, fi->state));
+			/* Logged an error, continue anyway. */
+
+		lu_compl_vlr_new_tmsi(fi);
+
+		/* Wait for TMSI ack */
+		return;
+	}
+
+	/* No TMSI needed, accept now. */
+	vlr->ops.tx_lu_acc(lcvp->msc_conn_ref, GSM_RESERVED_TMSI);
+	vlr_lu_compl_fsm_success(fi);
+}
+
+/* Waiting for TMSI confirmation */
+static void lu_compl_vlr_wait_tmsi(struct osmo_fsm_inst *fi, uint32_t event,
+				   void *data)
+{
+	struct lu_compl_vlr_priv *lcvp = fi->priv;
+	struct vlr_subscr *vsub = lcvp->vsub;
+
+	OSMO_ASSERT(event == LU_COMPL_VLR_E_NEW_TMSI_ACK);
+
+	if (!vsub || vsub->tmsi_new == GSM_RESERVED_TMSI) {
+		LOGPFSML(fi, LOGL_ERROR, "TMSI Realloc Compl implies that"
+			 " the subscriber has a new TMSI allocated, but"
+			 " the new TMSI is unset.\n");
+		vlr_lu_compl_fsm_failure(fi, GSM48_REJECT_NETWORK_FAILURE);
+		return;
+	}
+
+	vsub->tmsi = vsub->tmsi_new;
+	vsub->tmsi_new = GSM_RESERVED_TMSI;
+
+	vlr_lu_compl_fsm_success(fi);
+}
+
+static const struct osmo_fsm_state lu_compl_vlr_states[] = {
+	[LU_COMPL_VLR_S_INIT] = {
+		.in_event_mask = S(LU_COMPL_VLR_E_START),
+		.out_state_mask = S(LU_COMPL_VLR_S_DONE) |
+				  S(LU_COMPL_VLR_S_WAIT_SUB_PRES) |
+				  S(LU_COMPL_VLR_S_WAIT_IMEI),
+		.name = OSMO_STRINGIFY(LU_COMPL_VLR_S_INIT),
+		.action = lu_compl_vlr_init,
+	},
+	[LU_COMPL_VLR_S_WAIT_SUB_PRES] = {
+		.in_event_mask = S(LU_COMPL_VLR_E_SUB_PRES_COMPL),
+		.out_state_mask = S(LU_COMPL_VLR_S_WAIT_IMEI) |
+				  S(LU_COMPL_VLR_S_WAIT_IMEI_TMSI) |
+				  S(LU_COMPL_VLR_S_WAIT_TMSI_CNF) |
+				  S(LU_COMPL_VLR_S_DONE),
+		.name = OSMO_STRINGIFY(LU_COMPL_VLR_S_WAIT_SUB_PRES),
+		.action = lu_compl_vlr_wait_subscr_pres,
+	},
+	[LU_COMPL_VLR_S_WAIT_IMEI] = {
+		.in_event_mask = S(LU_COMPL_VLR_E_IMEI_CHECK_ACK) |
+				 S(LU_COMPL_VLR_E_IMEI_CHECK_NACK),
+		.out_state_mask = S(LU_COMPL_VLR_S_DONE),
+		.name = OSMO_STRINGIFY(LU_COMPL_VLR_S_WAIT_IMEI),
+		.action = lu_compl_vlr_wait_imei,
+	},
+	[LU_COMPL_VLR_S_WAIT_IMEI_TMSI] = {
+		.in_event_mask = S(LU_COMPL_VLR_E_IMEI_CHECK_ACK) |
+				 S(LU_COMPL_VLR_E_IMEI_CHECK_NACK),
+		.out_state_mask = S(LU_COMPL_VLR_S_DONE) |
+				  S(LU_COMPL_VLR_S_WAIT_TMSI_CNF),
+		.name = OSMO_STRINGIFY(LU_COMPL_VLR_S_WAIT_IMEI_TMSI),
+		.action = lu_compl_vlr_wait_imei,
+	},
+	[LU_COMPL_VLR_S_WAIT_TMSI_CNF] = {
+		.in_event_mask = S(LU_COMPL_VLR_E_NEW_TMSI_ACK),
+		.out_state_mask = S(LU_COMPL_VLR_S_DONE),
+		.name = OSMO_STRINGIFY(LU_COMPL_VLR_S_WAIT_TMSI_CNF),
+		.action = lu_compl_vlr_wait_tmsi,
+	},
+	[LU_COMPL_VLR_S_DONE] = {
+		.name = OSMO_STRINGIFY(LU_COMPL_VLR_S_DONE),
+		.onenter = vlr_lu_compl_fsm_dispatch_result,
+	},
+};
+
+static struct osmo_fsm lu_compl_vlr_fsm = {
+	.name = "lu_compl_vlr_fsm",
+	.states = lu_compl_vlr_states,
+	.num_states = ARRAY_SIZE(lu_compl_vlr_states),
+	.allstate_event_mask = 0,
+	.allstate_action = NULL,
+	.log_subsys = DVLR,
+	.event_names = lu_compl_vlr_event_names,
+};
+
+struct osmo_fsm_inst *
+lu_compl_vlr_proc_alloc(struct osmo_fsm_inst *parent,
+			struct vlr_subscr *vsub,
+			void *msc_conn_ref,
+			uint32_t parent_event_success,
+			uint32_t parent_event_failure,
+			bool assign_tmsi)
+{
+	struct osmo_fsm_inst *fi;
+	struct lu_compl_vlr_priv *lcvp;
+
+	fi = osmo_fsm_inst_alloc_child(&lu_compl_vlr_fsm, parent,
+				       parent_event_failure);
+	if (!fi)
+		return NULL;
+
+	lcvp = talloc_zero(fi, struct lu_compl_vlr_priv);
+	lcvp->vsub = vsub;
+	lcvp->msc_conn_ref = msc_conn_ref;
+	lcvp->parent_event_success = parent_event_success;
+	lcvp->parent_event_failure = parent_event_failure;
+	lcvp->assign_tmsi = assign_tmsi;
+	fi->priv = lcvp;
+
+	return fi;
+}
+
+
+/***********************************************************************
+ * Update_Location_Area_VLR, TS 23.012 Chapter 4.1.2.1
+ ***********************************************************************/
+
+static const struct value_string fsm_lu_event_names[] = {
+	OSMO_VALUE_STRING(VLR_ULA_E_UPDATE_LA),
+	OSMO_VALUE_STRING(VLR_ULA_E_SEND_ID_ACK),
+	OSMO_VALUE_STRING(VLR_ULA_E_SEND_ID_NACK),
+	OSMO_VALUE_STRING(VLR_ULA_E_AUTH_RES),
+	OSMO_VALUE_STRING(VLR_ULA_E_CIPH_RES),
+	OSMO_VALUE_STRING(VLR_ULA_E_ID_IMSI),
+	OSMO_VALUE_STRING(VLR_ULA_E_ID_IMEI),
+	OSMO_VALUE_STRING(VLR_ULA_E_ID_IMEISV),
+	OSMO_VALUE_STRING(VLR_ULA_E_HLR_LU_RES),
+	OSMO_VALUE_STRING(VLR_ULA_E_UPD_HLR_COMPL),
+	OSMO_VALUE_STRING(VLR_ULA_E_LU_COMPL_SUCCESS),
+	OSMO_VALUE_STRING(VLR_ULA_E_LU_COMPL_FAILURE),
+	OSMO_VALUE_STRING(VLR_ULA_E_NEW_TMSI_ACK),
+	{ 0, NULL }
+};
+
+struct lu_fsm_priv {
+	struct vlr_instance *vlr;
+	struct vlr_subscr *vsub;
+	void *msc_conn_ref;
+	struct osmo_fsm_inst *upd_hlr_vlr_fsm;
+	struct osmo_fsm_inst *lu_compl_vlr_fsm;
+	uint32_t parent_event_success;
+	uint32_t parent_event_failure;
+	void *parent_event_data;
+	enum vlr_fsm_result result;
+	uint8_t rej_cause;
+
+	enum vlr_lu_type type;
+	bool lu_by_tmsi;
+	char imsi[16];
+	uint32_t tmsi;
+	struct osmo_location_area_id old_lai;
+	struct osmo_location_area_id new_lai;
+	bool authentication_required;
+	enum vlr_ciph ciphering_required;
+	bool is_r99;
+	bool is_utran;
+	bool assign_tmsi;
+};
+
+
+/* Determine if given location area is served by this VLR */
+static bool lai_in_this_vlr(struct vlr_instance *vlr,
+			    const struct osmo_location_area_id *lai)
+{
+	/* TODO: VLR needs to keep a locally configued list of LAIs */
+	return true;
+}
+
+/* Determine if authentication is required */
+static bool is_auth_required(struct lu_fsm_priv *lfp)
+{
+	/* The cases where the authentication procedure should be used
+	 * are defined in 3GPP TS 33.102 */
+	/* For now we use a default value passed in to vlr_lu_fsm(). */
+	return lfp->authentication_required
+	       || (lfp->ciphering_required != VLR_CIPH_NONE);
+}
+
+/* Determine if ciphering is required */
+static bool is_ciph_required(struct lu_fsm_priv *lfp)
+{
+	return lfp->ciphering_required != VLR_CIPH_NONE;
+}
+
+/* Determine if a HLR Update is required */
+static bool hlr_update_needed(struct vlr_subscr *vsub)
+{
+	/* TODO: properly decide this, rather than always assuming we
+	 * need to update the HLR. */
+	return true;
+}
+
+static void lu_fsm_dispatch_result(struct osmo_fsm_inst *fi,
+				   uint32_t prev_state)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	if (!fi->proc.parent) {
+		LOGPFSML(fi, LOGL_ERROR, "No parent FSM\n");
+		return;
+	}
+	osmo_fsm_inst_dispatch(fi->proc.parent,
+			       (lfp->result == VLR_FSM_RESULT_SUCCESS)
+			       ? lfp->parent_event_success
+			       : lfp->parent_event_failure,
+			       lfp->parent_event_data);
+}
+
+static void _lu_fsm_done(struct osmo_fsm_inst *fi,
+			 enum vlr_fsm_result result)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	lfp->result = result;
+	osmo_fsm_inst_state_chg(fi, VLR_ULA_S_DONE, 0, 0);
+}
+
+static void lu_fsm_success(struct osmo_fsm_inst *fi)
+{
+	_lu_fsm_done(fi, VLR_FSM_RESULT_SUCCESS);
+}
+
+static void lu_fsm_failure(struct osmo_fsm_inst *fi, uint8_t rej_cause)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	if (rej_cause)
+		lfp->vlr->ops.tx_lu_rej(lfp->msc_conn_ref, rej_cause);
+	_lu_fsm_done(fi, VLR_FSM_RESULT_FAILURE);
+}
+
+static void vlr_loc_upd_start_lu_compl_fsm(struct osmo_fsm_inst *fi)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	lfp->lu_compl_vlr_fsm =
+		lu_compl_vlr_proc_alloc(fi, lfp->vsub, lfp->msc_conn_ref,
+					VLR_ULA_E_LU_COMPL_SUCCESS,
+					VLR_ULA_E_LU_COMPL_FAILURE,
+					lfp->assign_tmsi);
+
+	osmo_fsm_inst_dispatch(lfp->lu_compl_vlr_fsm, LU_COMPL_VLR_E_START, NULL);
+}
+
+static void lu_fsm_discard_lu_compl_fsm(struct osmo_fsm_inst *fi)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	if (!lfp->lu_compl_vlr_fsm)
+		return;
+	osmo_fsm_inst_term(lfp->lu_compl_vlr_fsm, OSMO_FSM_TERM_PARENT, NULL);
+}
+
+/* 4.1.2.1 Node 4 */
+static void vlr_loc_upd_node_4(struct osmo_fsm_inst *fi)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	struct vlr_subscr *vsub = lfp->vsub;
+	bool hlr_unknown = false;
+
+	LOGPFSM(fi, "%s()\n", __func__);
+
+	if (hlr_unknown) {
+		/* FIXME: Delete subscriber record */
+		/* LU REJ: Roaming not allowed */
+		lu_fsm_failure(fi, GSM48_REJECT_ROAMING_NOT_ALLOWED);
+	} else {
+		/* Update_HLR_VLR */
+		osmo_fsm_inst_state_chg(fi, VLR_ULA_S_WAIT_HLR_UPD,
+					LU_TIMEOUT_LONG, 0);
+		lfp->upd_hlr_vlr_fsm =
+			upd_hlr_vlr_proc_start(fi, vsub, VLR_ULA_E_UPD_HLR_COMPL);
+	}
+}
+
+/* 4.1.2.1 Node B */
+static void vlr_loc_upd_node_b(struct osmo_fsm_inst *fi)
+{
+	LOGPFSM(fi, "%s()\n", __func__);
+
+	/* FIXME */
+	if (0) { /* IMEISV or PgA to send */
+		vlr_loc_upd_node_4(fi);
+	} else {
+		/* Location_Update_Completion */
+		osmo_fsm_inst_state_chg(fi, VLR_ULA_S_WAIT_LU_COMPL,
+					LU_TIMEOUT_LONG, 0);
+		vlr_loc_upd_start_lu_compl_fsm(fi);
+	}
+}
+
+/* Non-standard: after Ciphering Mode Complete (or no ciph required) */
+static void vlr_loc_upd_post_ciph(struct osmo_fsm_inst *fi)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	struct vlr_subscr *vsub = lfp->vsub;
+
+	LOGPFSM(fi, "%s()\n", __func__);
+
+	OSMO_ASSERT(vsub);
+
+	vsub->conf_by_radio_contact_ind = true;
+	/* Update LAI */
+	vsub->cgi.lai = lfp->new_lai;
+	vsub->dormant_ind = false;
+	vsub->cancel_loc_rx = false;
+	if (hlr_update_needed(vsub)) {
+		vlr_loc_upd_node_4(fi);
+	} else {
+		/* TODO: ADD Support */
+		/* TODO: Node A: PgA Support */
+		vlr_loc_upd_node_b(fi);
+	}
+}
+
+/* 4.1.2.1 after Authentication successful (or no auth rqd) */
+static void vlr_loc_upd_post_auth(struct osmo_fsm_inst *fi)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	struct vlr_subscr *vsub = lfp->vsub;
+
+	LOGPFSM(fi, "%s()\n", __func__);
+
+	OSMO_ASSERT(vsub);
+
+	if (!is_ciph_required(lfp)) {
+		vlr_loc_upd_post_ciph(fi);
+		return;
+	}
+
+	if (vlr_set_ciph_mode(vsub->vlr, fi, lfp->msc_conn_ref,
+			      lfp->ciphering_required,
+			      vsub->vlr->cfg.retrieve_imeisv)) {
+		LOGPFSML(fi, LOGL_ERROR,
+			 "Failed to send Ciphering Mode Command\n");
+		vlr_lu_compl_fsm_failure(fi, GSM48_REJECT_NETWORK_FAILURE);
+		return;
+	}
+
+	osmo_fsm_inst_state_chg(fi, VLR_ULA_S_WAIT_CIPH, LU_TIMEOUT_LONG, 0);
+}
+
+static void vlr_loc_upd_node1(struct osmo_fsm_inst *fi)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	struct vlr_subscr *vsub = lfp->vsub;
+
+	LOGPFSM(fi, "%s()\n", __func__);
+
+	OSMO_ASSERT(vsub);
+
+	if (is_auth_required(lfp)) {
+		/* Authenticate_VLR */
+		osmo_fsm_inst_state_chg(fi, VLR_ULA_S_WAIT_AUTH,
+					LU_TIMEOUT_LONG, 0);
+		vsub->auth_fsm = auth_fsm_start(lfp->vsub, fi->log_level,
+						fi, VLR_ULA_E_AUTH_RES,
+						lfp->is_r99,
+						lfp->is_utran);
+	} else {
+		/* no need for authentication */
+		vlr_loc_upd_post_auth(fi);
+	}
+}
+
+static void vlr_loc_upd_want_imsi(struct osmo_fsm_inst *fi)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	struct vlr_instance *vlr = lfp->vlr;
+
+	LOGPFSM(fi, "%s()\n", __func__);
+
+	OSMO_ASSERT(lfp->vsub);
+
+	/* Obtain_IMSI_VLR */
+	osmo_fsm_inst_state_chg(fi, VLR_ULA_S_WAIT_IMSI,
+				vlr_timer(vlr, 3270), 3270);
+	vlr->ops.tx_id_req(lfp->msc_conn_ref, GSM_MI_TYPE_IMSI);
+	/* will continue at vlr_loc_upd_node1() once IMSI arrives */
+}
+
+static int assoc_lfp_with_sub(struct osmo_fsm_inst *fi, struct vlr_subscr *vsub)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	struct vlr_instance *vlr = lfp->vlr;
+
+	if (vsub->lu_fsm) {
+		LOGPFSML(fi, LOGL_ERROR,
+			 "A Location Updating process is already pending for"
+			 " this subscriber. Aborting.\n");
+		/* Also get rid of the other pending LU attempt? */
+		/*lu_fsm_failure(vsub->lu_fsm, GSM48_REJECT_CONGESTION);*/
+		lu_fsm_failure(fi, GSM48_REJECT_CONGESTION);
+		return -EINVAL;
+	}
+	vsub->lu_fsm = fi;
+	vsub->msc_conn_ref = lfp->msc_conn_ref;
+	/* FIXME: send new LAC to HLR? */
+	vsub->lac = lfp->new_lai.lac;
+	lfp->vsub = vsub;
+	/* Tell MSC to associate this subscriber with the given
+	 * connection */
+	vlr->ops.subscr_assoc(lfp->msc_conn_ref, lfp->vsub);
+	return 0;
+}
+
+static const char *lai_name(struct osmo_location_area_id *lai)
+{
+	static char buf[64];
+	snprintf(buf, sizeof(buf),"MCC:%u, MNC:%u, LAC:%u",
+		 lai->plmn.mcc, lai->plmn.mnc, lai->lac);
+	return buf;
+}
+
+/* 4.1.2.1: Subscriber (via MSC/SGSN) requests location update */
+static void _start_lu_main(struct osmo_fsm_inst *fi)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	struct vlr_instance *vlr = lfp->vlr;
+	struct vlr_subscr *vsub = NULL;
+	bool created;
+
+	/* TODO: PUESBINE related handling */
+
+	/* Is previous LAI in this VLR? */
+	if (!lai_in_this_vlr(vlr, &lfp->old_lai)) {
+#if 0
+		/* FIXME: check previous VLR, (3) */
+		osmo_fsm_inst_state_chg(fi, VLR_ULA_S_WAIT_PVLR,
+					LU_TIMEOUT_LONG, 0);
+		return;
+#endif
+		LOGPFSML(fi, LOGL_NOTICE, "LAI change from %s,"
+			 " but checking previous VLR not implemented\n",
+			 lai_name(&lfp->old_lai));
+	}
+
+	if (!lfp->imsi[0]) {
+		/* TMSI was used */
+		lfp->lu_by_tmsi = true;
+		/* TMSI clash: if a different subscriber already has this TMSI,
+		 * we will find that other subscriber in the VLR. So the IMSIs
+		 * would mismatch, but we don't know about it. Theoretically,
+		 * an authentication process would thwart any attempt to use
+		 * someone else's TMSI.
+		 * TODO: Otherwise we can ask for the IMSI and verify that it
+		 * matches the IMSI on record. */
+		vsub = vlr_subscr_find_or_create_by_tmsi(vlr, lfp->tmsi,
+							 &created);
+
+		if (!vsub) {
+			LOGPFSML(fi, LOGL_ERROR,
+				 "VLR subscriber allocation failed\n");
+			lu_fsm_failure(fi, GSM48_REJECT_SRV_OPT_TMP_OUT_OF_ORDER);
+			return;
+		}
+
+		vsub->sub_dataconf_by_hlr_ind = false;
+		if (assoc_lfp_with_sub(fi, vsub)) {
+			vlr_subscr_put(vsub);
+			return; /* error */
+		}
+
+		if (created)
+			vlr_loc_upd_want_imsi(fi);
+		else
+			vlr_loc_upd_node1(fi);
+		/* We cannot have MSC area change, as the VLR
+		 * serves only one MSC */
+		vlr_subscr_put(vsub);
+	} else {
+		/* IMSI was used */
+		vsub = vlr_subscr_find_or_create_by_imsi(vlr, lfp->imsi, NULL);
+
+		if (!vsub) {
+			LOGPFSML(fi, LOGL_ERROR,
+				 "VLR subscriber allocation failed\n");
+			lu_fsm_failure(fi, GSM48_REJECT_SRV_OPT_TMP_OUT_OF_ORDER);
+			vlr_subscr_put(vsub);
+			return;
+		}
+
+		vsub->sub_dataconf_by_hlr_ind = false;
+		if (assoc_lfp_with_sub(fi, vsub)) {
+			vlr_subscr_put(vsub);
+			return; /* error */
+		}
+		vlr_loc_upd_node1(fi);
+		vlr_subscr_put(vsub);
+	}
+}
+
+
+static void lu_fsm_idle(struct osmo_fsm_inst *fi, uint32_t event,
+			void *data)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	struct vlr_instance *vlr = lfp->vlr;
+
+	OSMO_ASSERT(event == VLR_ULA_E_UPDATE_LA);
+
+	if (1) { // FIXME
+	//if (lfp->type == VLR_LU_TYPE_PERIODIC && lfp->vsub->imeisv[0])
+		/* R_IMEISV_IR1 passed */
+		_start_lu_main(fi);
+	} else {
+		vlr->ops.tx_id_req(lfp->msc_conn_ref, GSM_MI_TYPE_IMEISV);
+		osmo_fsm_inst_state_chg(fi, VLR_ULA_S_WAIT_IMEISV,
+					vlr_timer(vlr, 3270), 3270);
+	}
+}
+
+static void lu_fsm_wait_imeisv(struct osmo_fsm_inst *fi, uint32_t event,
+			       void *data)
+{
+	switch (event) {
+	case VLR_ULA_E_ID_IMEISV:
+		/* FIXME: copy IMEISV */
+		_start_lu_main(fi);
+		break;
+	default:
+		LOGPFSML(fi, LOGL_ERROR, "event without effect: %s\n",
+			 osmo_fsm_event_name(fi->fsm, event));
+		break;
+	}
+}
+
+/* Wait for response from Send_Identification to PVLR */
+static void lu_fsm_wait_pvlr(struct osmo_fsm_inst *fi, uint32_t event,
+			     void *data)
+{
+	switch (event) {
+	case VLR_ULA_E_SEND_ID_ACK:
+		vlr_loc_upd_node1(fi);
+		break;
+	case VLR_ULA_E_SEND_ID_NACK:
+		vlr_loc_upd_want_imsi(fi);
+		break;
+	default:
+		LOGPFSML(fi, LOGL_ERROR, "event without effect: %s\n",
+			 osmo_fsm_event_name(fi->fsm, event));
+		break;
+	}
+}
+
+/* Wait for result of Authenticate_VLR procedure */
+static void lu_fsm_wait_auth(struct osmo_fsm_inst *fi, uint32_t event,
+			     void *data)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	enum vlr_auth_fsm_result *res = data;
+	uint8_t rej_cause = 0;
+
+	OSMO_ASSERT(event == VLR_ULA_E_AUTH_RES);
+
+	lfp->upd_hlr_vlr_fsm = NULL;
+
+	if (res) {
+		switch (*res) {
+		case VLR_AUTH_RES_PASSED:
+			/* Result == Pass */
+			vlr_loc_upd_post_auth(fi);
+			return;
+		case VLR_AUTH_RES_ABORTED:
+			/* go to Idle with no response */
+			rej_cause = 0;
+			break;
+		case VLR_AUTH_RES_UNKNOWN_SUBSCR:
+			/* FIXME: delete subscribe record */
+			rej_cause = GSM48_REJECT_IMSI_UNKNOWN_IN_HLR;
+			break;
+		case VLR_AUTH_RES_AUTH_FAILED:
+			/* cause = illegal subscriber */
+			rej_cause = GSM48_REJECT_ILLEGAL_MS;
+			break;
+		case VLR_AUTH_RES_PROC_ERR:
+			/* cause = system failure */
+			rej_cause = GSM48_REJECT_NETWORK_FAILURE;
+			break;
+		default:
+			LOGPFSML(fi, LOGL_ERROR, "event without effect: %s\n",
+				 osmo_fsm_event_name(fi->fsm, event));
+			break;
+		}
+	} else
+		rej_cause = GSM48_REJECT_NETWORK_FAILURE;
+
+	lu_fsm_failure(fi, rej_cause);
+}
+
+static void lu_fsm_wait_ciph(struct osmo_fsm_inst *fi, uint32_t event,
+			     void *data)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	struct vlr_subscr *vsub = lfp->vsub;
+	struct vlr_ciph_result res = { .cause = VLR_CIPH_REJECT };
+
+	OSMO_ASSERT(event == VLR_ULA_E_CIPH_RES);
+
+	if (!data)
+		LOGPFSML(fi, LOGL_ERROR, "invalid ciphering result: NULL\n");
+	else
+		res = *(struct vlr_ciph_result*)data;
+
+	switch (res.cause) {
+	case VLR_CIPH_COMPL:
+		break;
+	case VLR_CIPH_REJECT:
+		LOGPFSM(fi, "ciphering rejected\n");
+		lu_fsm_failure(fi, GSM48_REJECT_INVALID_MANDANTORY_INF);
+		return;
+	default:
+		LOGPFSML(fi, LOGL_ERROR, "invalid ciphering result: %d\n",
+			 res.cause);
+		lu_fsm_failure(fi, GSM48_REJECT_INVALID_MANDANTORY_INF);
+		return;
+	}
+
+	if (res.imeisv) {
+		LOGPFSM(fi, "got IMEISV: %s\n", res.imeisv);
+		vlr_subscr_set_imeisv(vsub, res.imeisv);
+	}
+	vlr_loc_upd_post_ciph(fi);
+}
+
+static void lu_fsm_wait_imsi(struct osmo_fsm_inst *fi, uint32_t event,
+			     void *data)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	struct vlr_subscr *vsub = lfp->vsub;
+	char *mi_string = data;
+
+	switch (event) {
+	case VLR_ULA_E_ID_IMSI:
+		vlr_subscr_set_imsi(vsub, mi_string);
+		vlr_loc_upd_node1(fi);
+		break;
+	default:
+		LOGPFSML(fi, LOGL_ERROR, "event without effect: %s\n",
+			 osmo_fsm_event_name(fi->fsm, event));
+		break;
+	}
+}
+
+/* At the end of Update_HLR_VLR */
+static void lu_fsm_wait_hlr_ul_res(struct osmo_fsm_inst *fi, uint32_t event,
+				   void *data)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+
+	switch (event) {
+	case VLR_ULA_E_HLR_LU_RES:
+		/* pass-through this event to Update_HLR_VLR */
+		if (data == NULL)
+			osmo_fsm_inst_dispatch(lfp->upd_hlr_vlr_fsm, UPD_HLR_VLR_E_UPD_LOC_ACK, NULL);
+		else
+			osmo_fsm_inst_dispatch(lfp->upd_hlr_vlr_fsm, UPD_HLR_VLR_E_UPD_LOC_NACK, data);
+		break;
+	case VLR_ULA_E_UPD_HLR_COMPL:
+		if (data == NULL) {
+			/* successful case */
+			osmo_fsm_inst_state_chg(fi, VLR_ULA_S_WAIT_LU_COMPL,
+						LU_TIMEOUT_LONG, 0);
+			vlr_loc_upd_start_lu_compl_fsm(fi);
+			/* continue in MSC ?!? */
+		} else {
+			/* unsuccessful case */
+			enum gsm48_gmm_cause cause =
+				*(enum gsm48_gmm_cause *)data;
+			if (0 /* procedure_error && vlr->cfg.standalone_mode */) {
+				osmo_fsm_inst_state_chg(fi,
+						VLR_ULA_S_WAIT_LU_COMPL_STANDALONE,
+						LU_TIMEOUT_LONG, 0);
+				vlr_loc_upd_start_lu_compl_fsm(fi);
+			} else {
+				lu_fsm_failure(fi, cause);
+			}
+		}
+		break;
+	default:
+		LOGPFSML(fi, LOGL_ERROR, "event without effect: %s\n",
+			 osmo_fsm_event_name(fi->fsm, event));
+		break;
+	}
+}
+
+/* Wait for end of Location_Update_Completion_VLR */
+static void lu_fsm_wait_lu_compl(struct osmo_fsm_inst *fi, uint32_t event,
+				 void *data)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	uint8_t cause;
+
+	switch (event) {
+	case VLR_ULA_E_NEW_TMSI_ACK:
+		osmo_fsm_inst_dispatch(lfp->lu_compl_vlr_fsm,
+				       LU_COMPL_VLR_E_NEW_TMSI_ACK, NULL);
+		break;
+	case VLR_ULA_E_ID_IMEI:
+		osmo_fsm_inst_dispatch(lfp->lu_compl_vlr_fsm,
+				       LU_COMPL_VLR_E_IMEI_CHECK_ACK, NULL);
+		break;
+	case VLR_ULA_E_LU_COMPL_SUCCESS:
+		lu_fsm_discard_lu_compl_fsm(fi);
+
+		/* Update Register */
+		/* TODO: Set_Notification_Type 23.078 */
+		/* TODO: Notify_gsmSCF 23.078 */
+		/* TODO: Authenticated Radio Contact Established -> ARC */
+		lu_fsm_success(fi);
+		break;
+	case VLR_ULA_E_LU_COMPL_FAILURE:
+		cause = GSM48_REJECT_NETWORK_FAILURE;
+		if (data)
+			cause = *(uint8_t*)data;
+		lu_fsm_discard_lu_compl_fsm(fi);
+		lu_fsm_failure(fi, cause);
+		break;
+	default:
+		LOGPFSML(fi, LOGL_ERROR, "event without effect: %s\n",
+			 osmo_fsm_event_name(fi->fsm, event));
+		break;
+	}
+}
+
+/* Wait for end of Location_Update_Completion_VLR (standalone case) */
+static void lu_fsm_wait_lu_compl_standalone(struct osmo_fsm_inst *fi,
+					uint32_t event, void *data)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	struct vlr_subscr *vsub = lfp->vsub;
+	uint8_t cause;
+
+	switch (event) {
+	case VLR_ULA_E_NEW_TMSI_ACK:
+		osmo_fsm_inst_dispatch(lfp->lu_compl_vlr_fsm,
+				       LU_COMPL_VLR_E_NEW_TMSI_ACK, NULL);
+		break;
+	case VLR_ULA_E_LU_COMPL_SUCCESS:
+		lu_fsm_discard_lu_compl_fsm(fi);
+		vsub->sub_dataconf_by_hlr_ind = false;
+		lu_fsm_success(fi);
+		break;
+	case VLR_ULA_E_LU_COMPL_FAILURE:
+		vsub->sub_dataconf_by_hlr_ind = false;
+		cause = GSM48_REJECT_NETWORK_FAILURE;
+		if (data)
+			cause = *(uint8_t*)data;
+		lu_fsm_discard_lu_compl_fsm(fi);
+		lu_fsm_failure(fi, cause);
+		break;
+	default:
+		LOGPFSML(fi, LOGL_ERROR, "event without effect: %s\n",
+			 osmo_fsm_event_name(fi->fsm, event));
+		break;
+	}
+}
+
+static const struct osmo_fsm_state vlr_lu_fsm_states[] = {
+	[VLR_ULA_S_IDLE] = {
+		.in_event_mask = S(VLR_ULA_E_UPDATE_LA),
+		.out_state_mask = S(VLR_ULA_S_WAIT_IMEISV) |
+				  S(VLR_ULA_S_WAIT_PVLR) |
+				  S(VLR_ULA_S_WAIT_IMSI) |
+				  S(VLR_ULA_S_WAIT_AUTH) |
+				  S(VLR_ULA_S_WAIT_HLR_UPD) |
+				  S(VLR_ULA_S_DONE),
+		.name = OSMO_STRINGIFY(VLR_ULA_S_IDLE),
+		.action = lu_fsm_idle,
+	},
+	[VLR_ULA_S_WAIT_IMEISV] = {
+		.in_event_mask = S(VLR_ULA_E_ID_IMEISV),
+		.out_state_mask = S(VLR_ULA_S_WAIT_PVLR) |
+				  S(VLR_ULA_S_WAIT_IMSI) |
+				  S(VLR_ULA_S_DONE),
+		.name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_IMEISV),
+		.action = lu_fsm_wait_imeisv,
+	},
+	[VLR_ULA_S_WAIT_PVLR] = {
+		.in_event_mask = S(VLR_ULA_E_SEND_ID_ACK) |
+				 S(VLR_ULA_E_SEND_ID_NACK),
+		.out_state_mask = S(VLR_ULA_S_WAIT_IMSI) |
+				  S(VLR_ULA_S_WAIT_AUTH) |
+				  S(VLR_ULA_S_DONE),
+		.name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_PVLR),
+		.action = lu_fsm_wait_pvlr,
+	},
+	[VLR_ULA_S_WAIT_AUTH] = {
+		.in_event_mask = S(VLR_ULA_E_AUTH_RES),
+		.out_state_mask = S(VLR_ULA_S_WAIT_CIPH) |
+				  S(VLR_ULA_S_WAIT_LU_COMPL) |
+				  S(VLR_ULA_S_WAIT_HLR_UPD) |
+				  S(VLR_ULA_S_DONE),
+		.name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_AUTH),
+		.action = lu_fsm_wait_auth,
+	},
+	[VLR_ULA_S_WAIT_CIPH] = {
+		.name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_CIPH),
+		.in_event_mask = S(VLR_ULA_E_CIPH_RES),
+		.out_state_mask = S(VLR_ULA_S_WAIT_LU_COMPL) |
+				  S(VLR_ULA_S_WAIT_HLR_UPD) |
+				  S(VLR_ULA_S_DONE),
+		.action = lu_fsm_wait_ciph,
+	},
+	[VLR_ULA_S_WAIT_IMSI] = {
+		.in_event_mask = S(VLR_ULA_E_ID_IMSI),
+		.out_state_mask = S(VLR_ULA_S_WAIT_AUTH) |
+				  S(VLR_ULA_S_WAIT_HLR_UPD) |
+				  S(VLR_ULA_S_DONE),
+		.name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_IMSI),
+		.action = lu_fsm_wait_imsi,
+	},
+	[VLR_ULA_S_WAIT_HLR_UPD] = {
+		.in_event_mask = S(VLR_ULA_E_HLR_LU_RES) |
+				 S(VLR_ULA_E_UPD_HLR_COMPL),
+		.out_state_mask = S(VLR_ULA_S_WAIT_LU_COMPL) |
+				  S(VLR_ULA_S_WAIT_LU_COMPL_STANDALONE) |
+				  S(VLR_ULA_S_DONE),
+		.name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_HLR_UPD),
+		.action = lu_fsm_wait_hlr_ul_res,
+	},
+	[VLR_ULA_S_WAIT_LU_COMPL] = {
+		.in_event_mask = S(VLR_ULA_E_LU_COMPL_SUCCESS) |
+				 S(VLR_ULA_E_LU_COMPL_FAILURE) |
+				 S(VLR_ULA_E_NEW_TMSI_ACK) |
+				 S(VLR_ULA_E_ID_IMEI) |
+				 S(VLR_ULA_E_ID_IMEISV),
+		.out_state_mask = S(VLR_ULA_S_DONE),
+		.name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_LU_COMPL),
+		.action = lu_fsm_wait_lu_compl,
+	},
+	[VLR_ULA_S_WAIT_LU_COMPL_STANDALONE] = {
+		.in_event_mask = S(VLR_ULA_E_LU_COMPL_SUCCESS) |
+				 S(VLR_ULA_E_LU_COMPL_FAILURE) |
+				 S(VLR_ULA_E_NEW_TMSI_ACK),
+		.out_state_mask = S(VLR_ULA_S_DONE),
+		.name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_LU_COMPL_STANDALONE),
+		.action = lu_fsm_wait_lu_compl_standalone,
+	},
+	[VLR_ULA_S_DONE] = {
+		.name = OSMO_STRINGIFY(VLR_ULA_S_DONE),
+		.onenter = lu_fsm_dispatch_result,
+	},
+};
+
+static void fsm_lu_cleanup(struct osmo_fsm_inst *fi, enum osmo_fsm_term_cause cause)
+{
+	struct lu_fsm_priv *lfp = fi->priv;
+	struct vlr_subscr *vsub = lfp->vsub;
+
+	LOGPFSM(fi, "fsm_lu_cleanup called with cause %s\n",
+		osmo_fsm_term_cause_name(cause));
+	if (vsub && vsub->lu_fsm == fi)
+		vsub->lu_fsm = NULL;
+}
+
+static struct osmo_fsm vlr_lu_fsm = {
+	.name = "vlr_lu_fsm",
+	.states = vlr_lu_fsm_states,
+	.num_states = ARRAY_SIZE(vlr_lu_fsm_states),
+	.allstate_event_mask = 0,
+	.allstate_action = NULL,
+	.log_subsys = DVLR,
+	.event_names = fsm_lu_event_names,
+	.cleanup = fsm_lu_cleanup,
+};
+
+struct osmo_fsm_inst *
+vlr_loc_update(struct osmo_fsm_inst *parent,
+	       uint32_t parent_event_success,
+	       uint32_t parent_event_failure,
+	       void *parent_event_data,
+	       struct vlr_instance *vlr, void *msc_conn_ref,
+	       enum vlr_lu_type type, uint32_t tmsi, const char *imsi,
+	       const struct osmo_location_area_id *old_lai,
+	       const struct osmo_location_area_id *new_lai,
+	       bool authentication_required,
+	       enum vlr_ciph ciphering_required,
+	       bool is_r99, bool is_utran,
+	       bool assign_tmsi)
+{
+	struct osmo_fsm_inst *fi;
+	struct lu_fsm_priv *lfp;
+
+	fi = osmo_fsm_inst_alloc_child(&vlr_lu_fsm, parent, parent_event_failure);
+	if (!fi)
+		return NULL;
+
+	lfp = talloc_zero(fi, struct lu_fsm_priv);
+	lfp->vlr = vlr;
+	lfp->msc_conn_ref = msc_conn_ref;
+	lfp->tmsi = tmsi;
+	lfp->type = type;
+	lfp->old_lai = *old_lai;
+	lfp->new_lai = *new_lai;
+	lfp->lu_by_tmsi = true;
+	lfp->parent_event_success = parent_event_success;
+	lfp->parent_event_failure = parent_event_failure;
+	lfp->parent_event_data = parent_event_data;
+	lfp->authentication_required = authentication_required;
+	lfp->ciphering_required = ciphering_required;
+	lfp->is_r99 = is_r99;
+	lfp->is_utran = is_utran;
+	lfp->assign_tmsi = assign_tmsi;
+	if (imsi) {
+		strncpy(lfp->imsi, imsi, sizeof(lfp->imsi)-1);
+		lfp->imsi[sizeof(lfp->imsi)-1] = '\0';
+		lfp->lu_by_tmsi = false;
+	}
+	fi->priv = lfp;
+
+	LOGPFSM(fi, "rev=%s net=%s%s%s\n",
+		is_r99 ? "R99" : "GSM",
+		is_utran ? "UTRAN" : "GERAN",
+		(authentication_required || ciphering_required)?
+		" Auth" : " (no Auth)",
+		(authentication_required || ciphering_required)?
+			(ciphering_required? "+Ciph" : " (no Ciph)")
+			: "");
+
+	osmo_fsm_inst_dispatch(fi, VLR_ULA_E_UPDATE_LA, NULL);
+
+	return fi;
+}
+
+/* Gracefully terminate an FSM created by vlr_loc_update() in case of external
+ * timeout (i.e. from MSC). */
+void vlr_loc_update_conn_timeout(struct osmo_fsm_inst *fi)
+{
+	if (!fi || fi->state == VLR_ULA_S_DONE)
+		return;
+	LOGPFSM(fi, "Connection timed out\n");
+	lu_fsm_failure(fi, GSM48_REJECT_CONGESTION);
+}
+
+void vlr_lu_fsm_init(void)
+{
+	osmo_fsm_register(&vlr_lu_fsm);
+	osmo_fsm_register(&upd_hlr_vlr_fsm);
+	osmo_fsm_register(&sub_pres_vlr_fsm);
+	osmo_fsm_register(&lu_compl_vlr_fsm);
+}