From 015fde9a2c4b6e722a9de5bfea2a14226806a231 Mon Sep 17 00:00:00 2001
From: Martin Holst Swende <martin@swende.se>
Date: Tue, 25 Jan 2022 14:45:30 +0100
Subject: [PATCH] eth/tracers: avoid using blockCtx concurrently (#24286)

---
 eth/tracers/api.go | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/eth/tracers/api.go b/eth/tracers/api.go
index 5e553c114..b16b68c1f 100644
--- a/eth/tracers/api.go
+++ b/eth/tracers/api.go
@@ -592,11 +592,11 @@ func (api *API) traceBlock(ctx context.Context, block *types.Block, config *Trac
 	if threads > len(txs) {
 		threads = len(txs)
 	}
-	blockCtx := core.NewEVMBlockContext(block.Header(), api.chainContext(ctx), nil)
 	blockHash := block.Hash()
 	for th := 0; th < threads; th++ {
 		pend.Add(1)
 		go func() {
+			blockCtx := core.NewEVMBlockContext(block.Header(), api.chainContext(ctx), nil)
 			defer pend.Done()
 			// Fetch and execute the next transaction trace tasks
 			for task := range jobs {
@@ -617,6 +617,7 @@ func (api *API) traceBlock(ctx context.Context, block *types.Block, config *Trac
 	}
 	// Feed the transactions into the tracers and return
 	var failed error
+	blockCtx := core.NewEVMBlockContext(block.Header(), api.chainContext(ctx), nil)
 	for i, tx := range txs {
 		// Send the trace task over for execution
 		jobs <- &txTraceTask{statedb: statedb.Copy(), index: i}