From 5e5c560d30d96ea86f4b7a0e0721f2e274720844 Mon Sep 17 00:00:00 2001
From: Ganesh Vanahalli <gvanahalli@offchainlabs.com>
Date: Wed, 13 Mar 2024 17:26:06 -0500
Subject: [PATCH] Switch to go-ethereum PoS API to write reorgs to blockchain

---
 core/blockchain_arbitrum.go | 18 +++---------------
 1 file changed, 3 insertions(+), 15 deletions(-)

diff --git a/core/blockchain_arbitrum.go b/core/blockchain_arbitrum.go
index 8468dda93b..55966e98cc 100644
--- a/core/blockchain_arbitrum.go
+++ b/core/blockchain_arbitrum.go
@@ -18,7 +18,7 @@
 package core
 
 import (
-	"errors"
+	"fmt"
 	"time"
 
 	"github.com/ethereum/go-ethereum/core/state"
@@ -40,21 +40,9 @@ func (bc *BlockChain) WriteBlockAndSetHeadWithTime(block *types.Block, receipts
 func (bc *BlockChain) ReorgToOldBlock(newHead *types.Block) error {
 	bc.wg.Add(1)
 	defer bc.wg.Done()
-	locked := bc.chainmu.TryLock()
-	if !locked {
-		return errors.New("couldn't catch lock to reorg")
+	if _, err := bc.SetCanonical(newHead); err != nil {
+		return fmt.Errorf("error reorging to old block: %w", err)
 	}
-	defer bc.chainmu.Unlock()
-	oldHead := bc.CurrentBlock()
-	if oldHead.Hash() == newHead.Hash() {
-		return nil
-	}
-	bc.writeHeadBlock(newHead)
-	err := bc.reorg(oldHead, newHead)
-	if err != nil {
-		return err
-	}
-	bc.chainHeadFeed.Send(ChainHeadEvent{Block: newHead})
 	return nil
 }