add extra error info when meet a unexpected el sync

eth/catalyst/api.go

@@ -36,6 +36,7 @@ import (
 	"github.com/ethereum/go-ethereum/miner"
 	"github.com/ethereum/go-ethereum/node"
 	"github.com/ethereum/go-ethereum/rpc"
+	"strings"
 )
 
 var (
@@ -681,6 +682,9 @@ func (api *ConsensusAPI) delayPayloadImport(block *types.Block) (engine.PayloadS
 		// that the parent state is missing and the syncer rejected extending the
 		// current cycle with the new payload.
 		log.Warn("Ignoring payload with missing parent", "number", block.NumberU64(), "hash", block.Hash(), "parent", block.ParentHash(), "reason", err)
+		if strings.Contains(err.Error(), "forced head needed for startup") {
+			return engine.PayloadStatusV1{Status: engine.SYNCING}, err
+		}
 	} else {
 		// In non-full sync mode (i.e. snap sync) all payloads are rejected until
 		// snap sync terminates as snap sync relies on direct database injections

eth/catalyst/api_test.go

@@ -51,6 +51,7 @@ import (
 	"github.com/ethereum/go-ethereum/rpc"
 	"github.com/ethereum/go-ethereum/trie"
 	"github.com/mattn/go-colorable"
+	"strings"
 )
 
 var (
@@ -863,7 +864,7 @@ func TestTrickRemoteBlockCache(t *testing.T) {
 	// feed the payloads to node B
 	for _, payload := range invalidChain {
 		status, err := apiB.NewPayloadV1(*payload)
-		if err != nil {
+		if err != nil && !strings.Contains(err.Error(), "forced head needed for startup") {
 			panic(err)
 		}
 		if status.Status == engine.VALID {