fix(eth): initialize engine with finalized chain config, fix #2138 by gzliudan · Pull Request #2180 · XinFinOrg/XDPoSChain

gzliudan · 2026-03-13T02:07:55Z

Proposed changes

Reorder initialization in eth.New so the effective chain config is resolved and persisted via core.SetupGenesisBlock before creating the consensus engine.

Background:

On first sync from genesis, LoadChainConfig could return a stored/incomplete config (notably with XDPoS.V2 unset in legacy testnet setups).
Creating XDPoS before finalizing genesis config could trigger mainnet V2 fallback and log/behavior mismatches around SwitchBlock.

Proof:
Add a log in function func (x *XDPoS) VerifyHeaders:

	log.Info("VerifyHeaders",
		"switch block in chain config", chain.Config().XDPoS.V2.SwitchBlock.Uint64(),
		"switch block in V2 config", x.config.V2.SwitchBlock.Uint64(),
	)

Result:

"switch block in chain config"=56,828,700 "switch block in V2 config"=80,370,000

What changed:

Replace early LoadChainConfig usage with SetupGenesisBlock in eth.New.
Keep ConfigCompatError semantics consistent with core/blockchain initialization: fail only on non-compat errors.
Initialize consensus engine after finalized chainConfig is available.

Result:

Consensus engine now starts with finalized network config on first boot.
Avoids incorrect V2 fallback parameters (e.g. wrong SwitchBlock) during initial testnet sync.

Tests:

Added regression tests in eth/backend_test.go to cover legacy missing-V2 repair and SetupGenesisBlock idempotency.

fix #2138

Types of changes

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Checklist

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This PR has sufficient test coverage (unit/integration test) OR I have provided reason in the PR description for not having test coverage
Tested on a private network from the genesis block and monitored the chain operating correctly for multiple epochs.
Provide an end-to-end test plan in the PR description on how to manually test it on the devnet/testnet.
Tested the backwards compatibility.
Tested with XDC nodes running this version co-exist with those running the previous version.
Relevant documentation has been updated as part of this PR
N/A

coderabbitai · 2026-03-13T02:08:11Z

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Copilot

Pull request overview

This PR addresses a sync failure at the first XDPoS v2 block when syncing from genesis (#2138) by ensuring the effective genesis/chain configuration is resolved (and stored when possible) before the consensus engine is constructed.

Changes:

Replace core.LoadChainConfig with core.SetupGenesisBlock during eth.New initialization.
Construct the consensus engine after resolving the chain config, and reuse the instance when building the Ethereum service.

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

eth/backend.go

@@ -141,6 +141,7 @@ func New(stack *node.Node, config *ethconfig.Config, XDCXServ *XDCx.XDCX, lendin
 		networkID = chainConfig.ChainID.Uint64()
 	}
 	common.CopyConstants(networkID)
+	engine := CreateConsensusEngine(stack, chainConfig, chainDb)


eth/backend.go

@@ -141,6 +141,7 @@ func New(stack *node.Node, config *ethconfig.Config, XDCXServ *XDCx.XDCX, lendin
 		networkID = chainConfig.ChainID.Uint64()
 	}
 	common.CopyConstants(networkID)
+	engine := CreateConsensusEngine(stack, chainConfig, chainDb)


eth/backend.go

+	// Resolve and persist the effective chain config before constructing
+	// the consensus engine so it always initializes with final network settings.


…g#2138 Reorder initialization in eth.New so the effective chain config is resolved and persisted via core.SetupGenesisBlock before creating the consensus engine. Background: - On first sync from genesis, LoadChainConfig could return a stored/incomplete config (notably with XDPoS.V2 unset in legacy testnet setups). - Creating XDPoS before finalizing genesis config could trigger mainnet V2 fallback and log/behavior mismatches around SwitchBlock. What changed: - Replace early LoadChainConfig usage with SetupGenesisBlock in eth.New. - Keep ConfigCompatError semantics consistent with core/blockchain initialization: fail only on non-compat errors. - Initialize consensus engine after finalized chainConfig is available. Result: - Consensus engine now starts with finalized network config on first boot. - Avoids incorrect V2 fallback parameters (e.g. wrong SwitchBlock) during initial testnet sync. Tests: - Added regression tests in eth/backend_test.go to cover legacy missing-V2 repair and SetupGenesisBlock idempotency.

gzliudan requested review from AnilChinchawale, anunay-xin, benjamin202410, Copilot, liam-lai and wanwiset25 March 13, 2026 02:07

Copilot started reviewing on behalf of gzliudan March 13, 2026 02:08 View session

Copilot AI reviewed Mar 13, 2026

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gzliudan force-pushed the fix-sync-from-genesis branch from 1676ccd to 72382c3 Compare March 13, 2026 02:21

gzliudan mentioned this pull request Mar 13, 2026

sync fails at first v2 block only when sync from genesis block #2138

Closed

gzliudan changed the title ~~fix(eth): setup genesis config before engine init, fix #2138~~ fix(eth): initialize engine with finalized chain config, fix #2138 Mar 13, 2026

gzliudan force-pushed the fix-sync-from-genesis branch from 72382c3 to 372c5c4 Compare March 13, 2026 02:28

benjamin202410 approved these changes Mar 14, 2026

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fix(eth): initialize engine with finalized chain config, fix #2138#2180

fix(eth): initialize engine with finalized chain config, fix #2138#2180
gzliudan wants to merge 1 commit intoXinFinOrg:dev-upgradefrom
gzliudan:fix-sync-from-genesis

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		// Resolve and persist the effective chain config before constructing
		// the consensus engine so it always initializes with final network settings.

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gzliudan commented Mar 13, 2026 •

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