qcacld-3.0: LFR2 failed for deleting wrong pe session

During LFR2, new pe session is created before old pe session
deleted, the 2 pe sessions have different pe session id, but
same vdev id.
After change-Id: Ib2e7c72e0636765341792a79aa12968a84ed4879,
When delete old pe session DPH Entry,  get pe session by vdev
id instead of pe session id, since both new and old session have
same vdev id, so there is 50% chance to get wrong pe session.
then DPH Entry for STA 1 missing issue happens, then no reassoc
happens.

Fix: When delete old pe session DPH Entry,  get pe session by
both vdev id and PE mlm state: eLIM_MLM_WT_DEL_BSS_RSP_STATE.

Change-Id: I207a4291cd26175ea7013fb2f2a0c27865304db2
CRs-Fixed: 2593194

core/mac/src/pe/include/lim_session.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012-2019 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2012-2020 The Linux Foundation. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for
  * any purpose with or without fee is hereby granted, provided that the
@@ -652,6 +652,24 @@ struct pe_session *pe_find_session_by_bssid(struct mac_context *mac, uint8_t *bs
 struct pe_session *pe_find_session_by_vdev_id(struct mac_context *mac,
 					      uint8_t vdev_id);
 
+/**
+ * pe_find_session_by_vdev_id_and_state() - Find PE session by vdev_id and
+ * mlm state.
+ * @mac:             pointer to global adapter context
+ * @vdev_id:         vdev id the session
+ * @vdev_id:         vdev id the session
+ *
+ * During LFR2 roaming, new pe session is created before old pe session
+ * deleted, the 2 pe sessions have different pe session id, but same vdev id,
+ * can't get correct pe session by vdev id at this time.
+ *
+ * Return: pointer to the session context or NULL if session is not found.
+ */
+struct pe_session
+*pe_find_session_by_vdev_id_and_state(struct mac_context *mac,
+				      uint8_t vdev_id,
+				      enum eLimMlmStates lim_state);
+
 /**
  * pe_find_session_by_peer_sta() - looks up the PE session given the Peer
  * Station Address.

core/mac/src/pe/lim/lim_send_sme_rsp_messages.c

@@ -1850,10 +1850,10 @@ void lim_handle_delete_bss_rsp(struct mac_context *mac,
 	struct pe_session *pe_session;
 
 	pe_session =
-		pe_find_session_by_vdev_id(mac, del_bss_rsp->vdev_id);
+	   pe_find_session_by_vdev_id_and_state(mac,
+						del_bss_rsp->vdev_id,
+						eLIM_MLM_WT_DEL_BSS_RSP_STATE);
 	if (!pe_session) {
-		pe_err("Session Does not exist for vdev id: %d",
-		       del_bss_rsp->vdev_id);
 		qdf_mem_free(del_bss_rsp);
 		return;
 	}

core/mac/src/pe/lim/lim_session.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011-2019 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2011-2020 The Linux Foundation. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for
  * any purpose with or without fee is hereby granted, provided that the
@@ -754,6 +754,25 @@ struct pe_session *pe_find_session_by_vdev_id(struct mac_context *mac,
 	return NULL;
 }
 
+struct pe_session
+*pe_find_session_by_vdev_id_and_state(struct mac_context *mac,
+				      uint8_t vdev_id,
+				      enum eLimMlmStates lim_state)
+{
+	uint8_t i;
+
+	for (i = 0; i < mac->lim.maxBssId; i++) {
+		if (mac->lim.gpSession[i].valid &&
+		    mac->lim.gpSession[i].vdev_id == vdev_id &&
+		    mac->lim.gpSession[i].limMlmState == lim_state)
+			return &mac->lim.gpSession[i];
+	}
+	pe_debug("Session lookup fails for vdev_id: %d, mlm state: %d",
+		 vdev_id, lim_state);
+
+	return NULL;
+}
+
 /*--------------------------------------------------------------------------
    \brief pe_find_session_by_session_id() - looks up the PE session given the session ID.