Fixes for validator set update for the initial dynasty

interchain/witness/interface.go

@@ -14,5 +14,6 @@ type ChainWitness interface {
 	Wait()
 	GetMainchainBlockHeight() (*big.Int, error)
 	GetValidatorSetByDynasty(dynasty *big.Int) (*score.ValidatorSet, error)
+	GetSubchainRegistrationHeight() (*big.Int, error)
 	GetInterChainEventCache() *siu.InterChainEventCache
 }

interchain/witness/metachain_witness.go

@@ -574,36 +574,38 @@ func (mw *MetachainWitness) updateValidatorSetCache(dynasty *big.Int) (*score.Va
 	// queryBlockHeight = big.NewInt(0).Add(queryBlockHeight, big.NewInt(1)) // increment by one to make sure the query block height falls into the dynasty
 	// vs, err := mw.chainRegistrarOnMainchain.GetValidatorSet(nil, mw.subchainID, queryBlockHeight)
 
-	adjustedDynasty := dynasty
-	registrationMainchainHeight, ok, err := mw.chainRegistrarOnMainchain.GetSubchainRegistrationHeight(nil, mw.subchainID)
-	if !ok {
-		errMsg := fmt.Sprintf("subchain with ID %v does not exist", mw.subchainID)
-		logger.Warnf("updateValidatorSetCache: %v", errMsg)
-		return nil, fmt.Errorf(errMsg)
-	}
-
-	if err != nil {
-		logger.Warnf("updateValidatorSetCache: %v", err)
-		return nil, err
-	}
-
-	registrationDynasty := scom.CalculateDynasty(registrationMainchainHeight)
-	if adjustedDynasty.Cmp(registrationDynasty) == 0 {
-		// Special handling for the initial dynasty query on the **Mainchain**:
-		// The initial set of validators hardcoded in the genesis snapshot should be
-		// in charge during the initial dyansty. However, if we directly query the
-		// initial dynasty, we would obtain an empty set since the validators registered
-		// on the mainchain takes charge only when the next dynasty begins. Hence, for
-		// the initial dyansty, we query the next dynasty instead, which should return
-		// a validator set that matches with the validator set hardcoded in the
-		// genesis snapshot.
-		adjustedDynasty = big.NewInt(0).Add(adjustedDynasty, big.NewInt(1))
-
-		logger.Debugf("Subchain %v registration main chain height: %v, registration dynasty: %v, dynasty: %v, adjustedDynasty: %v",
-			mw.subchainID, registrationMainchainHeight, registrationDynasty, dynasty, adjustedDynasty)
-	}
-
-	vs, err := mw.chainRegistrarOnMainchain.GetValidatorSet(nil, mw.subchainID, adjustedDynasty)
+	// adjustedDynasty := dynasty
+	// registrationMainchainHeight, ok, err := mw.chainRegistrarOnMainchain.GetSubchainRegistrationHeight(nil, mw.subchainID)
+	// if !ok {
+	// 	errMsg := fmt.Sprintf("subchain with ID %v does not exist", mw.subchainID)
+	// 	logger.Warnf("updateValidatorSetCache: %v", errMsg)
+	// 	return nil, fmt.Errorf(errMsg)
+	// }
+
+	// if err != nil {
+	// 	logger.Warnf("updateValidatorSetCache: %v", err)
+	// 	return nil, err
+	// }
+
+	// registrationDynasty := scom.CalculateDynasty(registrationMainchainHeight)
+	// if adjustedDynasty.Cmp(registrationDynasty) == 0 {
+	// 	// Special handling for the initial dynasty query on the **Mainchain**:
+	// 	// The initial set of validators hardcoded in the genesis snapshot should be
+	// 	// in charge during the initial dyansty. However, if we directly query the
+	// 	// initial dynasty, we would obtain an empty set since the validators registered
+	// 	// on the mainchain takes charge only when the next dynasty begins. Hence, for
+	// 	// the initial dyansty, we query the next dynasty instead, which should return
+	// 	// a validator set that matches with the validator set hardcoded in the
+	// 	// genesis snapshot.
+	// 	adjustedDynasty = big.NewInt(0).Add(adjustedDynasty, big.NewInt(1))
+
+	// 	logger.Debugf("Subchain %v registration main chain height: %v, registration dynasty: %v, dynasty: %v, adjustedDynasty: %v",
+	// 		mw.subchainID, registrationMainchainHeight, registrationDynasty, dynasty, adjustedDynasty)
+	// }
+
+	// vs, err := mw.chainRegistrarOnMainchain.GetValidatorSet(nil, mw.subchainID, adjustedDynasty)
+
+	vs, err := mw.chainRegistrarOnMainchain.GetValidatorSet(nil, mw.subchainID, dynasty)
 	validatorAddrs := vs.Validators
 	validatorStakes := vs.ShareAmounts
 
@@ -631,3 +633,19 @@ func (mw *MetachainWitness) updateValidatorSetCache(dynasty *big.Int) (*score.Va
 func (mw *MetachainWitness) GetInterChainEventCache() *siu.InterChainEventCache {
 	return mw.interChainEventCache
 }
+
+func (mw *MetachainWitness) GetSubchainRegistrationHeight() (*big.Int, error) {
+	registrationMainchainHeight, ok, err := mw.chainRegistrarOnMainchain.GetSubchainRegistrationHeight(nil, mw.subchainID)
+	if !ok {
+		errMsg := fmt.Sprintf("subchain with ID %v does not exist", mw.subchainID)
+		logger.Warnf("GetSubchainRegistrationHeight: %v", errMsg)
+		return nil, fmt.Errorf(errMsg)
+	}
+
+	if err != nil {
+		logger.Warnf("GetSubchainRegistrationHeight: %v", err)
+		return nil, err
+	}
+
+	return registrationMainchainHeight, nil
+}

ledger/ledger.go

@@ -666,6 +666,19 @@ func (ledger *Ledger) getNewDynastyAndValidatorSet(view *slst.StoreView) (enteri
 		return false, nil, nil
 	}
 
+	registrationMainchainHeight, err := ledger.metachainWitness.GetSubchainRegistrationHeight()
+	if err != nil {
+		logger.Warnf("Failed to get subchain registration height: %v", err)
+		return false, nil, nil
+	}
+
+	registrationDynasty := scom.CalculateDynasty(registrationMainchainHeight)
+	if currentDynasty.Cmp(registrationDynasty) == 0 {
+		// For the initial dynasty, i.e. the dynasty during which the subchain was registered, instead of querying
+		// the validator set from the main chain, we trust the validator set in the snapshot
+		return false, nil, nil
+	}
+
 	witnessedDynasty := scom.CalculateDynasty(mainchainBlockHeight)
 	witnessedValidatorSet, err := ledger.metachainWitness.GetValidatorSetByDynasty(witnessedDynasty)
 	if err != nil {