From be36b32b3e4d999a5504e22c4d69d2c521860c63 Mon Sep 17 00:00:00 2001
From: benjamin202410 <benjamin.franklin.git@gmail.com>
Date: Thu, 12 Mar 2026 12:12:49 -0700
Subject: [PATCH] fix(consensus): fix config object not reference to same one
 and concurrency issues and refactor access pattern (#2146)

* bug fix for using same config object

* update

* change log level to trace on ispochswtich

---------

Co-authored-by: liam.lai <liam.lai@babylonchain.io>
---
 consensus/XDPoS/engines/engine_v2/engine.go      | 12 ++++++++----
 consensus/XDPoS/engines/engine_v2/epochSwitch.go |  2 +-
 eth/hooks/engine_v2_hooks.go                     |  7 +++++--
 params/config.go                                 | 15 ++++++++++++---
 4 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/consensus/XDPoS/engines/engine_v2/engine.go b/consensus/XDPoS/engines/engine_v2/engine.go
index 01937fa625..a2da3d8616 100644
--- a/consensus/XDPoS/engines/engine_v2/engine.go
+++ b/consensus/XDPoS/engines/engine_v2/engine.go
@@ -1,6 +1,7 @@
 package engine_v2
 
 import (
+	"bytes"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -1115,8 +1116,6 @@ func (x *XDPoS_v2) saveRewardToFile(blockHash common.Hash, blockNumber uint64) {
 
 	log.Debug("[saveRewardToFile] Saved rewards", "filename", filename)
 	log.Debug("[saveRewardToFile] Saved rewards", "rewards", string(data))
-
-	return
 }
 
 func deepCloneJSON(original map[string]interface{}) (map[string]interface{}, error) {
@@ -1126,10 +1125,15 @@ func deepCloneJSON(original map[string]interface{}) (map[string]interface{}, err
 	}
 
 	var cloned map[string]interface{}
-	err = json.Unmarshal(data, &cloned)
-	if err != nil {
+	dec := json.NewDecoder(bytes.NewReader(data))
+	dec.UseNumber()
+	if err = dec.Decode(&cloned); err != nil {
 		return nil, fmt.Errorf("failed to unmarshal: %w", err)
 	}
 
 	return cloned, nil
 }
+
+func (x *XDPoS_v2) Config(r uint64) *params.V2Config {
+	return x.config.V2.Config(r)
+}
diff --git a/consensus/XDPoS/engines/engine_v2/epochSwitch.go b/consensus/XDPoS/engines/engine_v2/epochSwitch.go
index 9bcc061986..e4b222fce1 100644
--- a/consensus/XDPoS/engines/engine_v2/epochSwitch.go
+++ b/consensus/XDPoS/engines/engine_v2/epochSwitch.go
@@ -164,7 +164,7 @@ func (x *XDPoS_v2) IsEpochSwitch(header *types.Header) (bool, uint64, error) {
 		log.Info("[IsEpochSwitch] true, parent equals V2.SwitchBlock", "round", round, "number", header.Number.Uint64(), "hash", header.Hash())
 		return true, epochNum, nil
 	}
-	log.Debug("[IsEpochSwitch]", "is", parentRound < epochStartRound, "parentRound", parentRound, "round", round, "number", header.Number.Uint64(), "epochNum", epochNum, "hash", header.Hash().Hex())
+	log.Trace("[IsEpochSwitch]", "is", parentRound < epochStartRound, "parentRound", parentRound, "round", round, "number", header.Number.Uint64(), "epochNum", epochNum, "hash", header.Hash().Hex())
 	// if isEpochSwitch, add to cache
 	if parentRound < epochStartRound {
 		x.round2epochBlockInfo.Add(round, &types.BlockInfo{
diff --git a/eth/hooks/engine_v2_hooks.go b/eth/hooks/engine_v2_hooks.go
index 41a771ba60..194ba818b2 100644
--- a/eth/hooks/engine_v2_hooks.go
+++ b/eth/hooks/engine_v2_hooks.go
@@ -99,7 +99,8 @@ func AttachConsensusV2Hooks(adaptor *XDPoS.XDPoS, bc *core.BlockChain, chainConf
 			listBlockHash = append(listBlockHash, parentHash)
 		}
 
-		currentConfig := chain.Config().XDPoS.V2.Config(uint64(round))
+		currentConfig := adaptor.EngineV2.Config(uint64(round))
+
 		// add list not miner to penalties
 		preMasternodes := adaptor.EngineV2.GetMasternodesByHash(chain, currentHash)
 		penalties := []common.Address{}
@@ -286,7 +287,9 @@ func AttachConsensusV2Hooks(adaptor *XDPoS.XDPoS, bc *core.BlockChain, chainConf
 			log.Error("[HookReward] Fail to get round", "error", err)
 			return nil, err
 		}
-		currentConfig := chain.Config().XDPoS.V2.Config(uint64(round))
+
+		currentConfig := adaptor.EngineV2.Config(uint64(round))
+
 		// Get signers/signing tx count, and burned tokens in one epoch
 		signers, burnedInOneEpoch, err := GetSigningTxCount(adaptor, chain, header, parentState, currentConfig)
 
diff --git a/params/config.go b/params/config.go
index 93ddd0f123..c606847c26 100644
--- a/params/config.go
+++ b/params/config.go
@@ -840,11 +840,14 @@ func (v2 *V2) GetCurrentConfig() *V2Config {
 	}
 
 	// avoid CurrentConfig is changed by other goroutines
-	cpyConfig := *v2.CurrentConfig
-	return &cpyConfig
+	cfg := *v2.CurrentConfig
+	return &cfg
 }
 
 func (v2 *V2) Config(round uint64) *V2Config {
+	v2.lock.RLock()
+	defer v2.lock.RUnlock()
+
 	configRound := round
 	var index uint64
 
@@ -855,10 +858,16 @@ func (v2 *V2) Config(round uint64) *V2Config {
 			break
 		}
 	}
-	return v2.AllConfigs[index]
+
+	// avoid config is changed by other goroutines
+	cfg := *v2.AllConfigs[index]
+	return &cfg
 }
 
 func (v2 *V2) BuildConfigIndex() {
+	v2.lock.Lock()
+	defer v2.lock.Unlock()
+
 	list := slices.Collect(maps.Keys(v2.AllConfigs))
 	// Make it descending order
 	slices.SortFunc(list, func(a, b uint64) int {