Revert "core/state/snapshot: fix BAD BLOCK error when snapshot is gen…

…erating (ethereum#23635)"

This reverts commit 312e02b.

core/state/snapshot/generate.go

@@ -560,12 +560,6 @@ func (dl *diskLayer) generate(stats *generatorStats) {
 		default:
 		}
 		if batch.ValueSize() > ethdb.IdealBatchSize || abort != nil {
-			if bytes.Compare(currentLocation, dl.genMarker) < 0 {
-				log.Error("Snapshot generator went backwards",
-					"currentLocation", fmt.Sprintf("%x", currentLocation),
-					"genMarker", fmt.Sprintf("%x", dl.genMarker))
-			}
-
 			// Flush out the batch anyway no matter it's empty or not.
 			// It's possible that all the states are recovered and the
 			// generation indeed makes progress.
@@ -640,14 +634,8 @@ func (dl *diskLayer) generate(stats *generatorStats) {
 			stats.storage += common.StorageSize(1 + common.HashLength + dataLen)
 			stats.accounts++
 		}
-		marker := accountHash[:]
-		// If the snap generation goes here after interrupted, genMarker may go backward
-		// when last genMarker is consisted of accountHash and storageHash
-		if accMarker != nil && bytes.Equal(marker, accMarker) && len(dl.genMarker) > common.HashLength {
-			marker = dl.genMarker[:]
-		}
 		// If we've exceeded our batch allowance or termination was requested, flush to disk
-		if err := checkAndFlush(marker); err != nil {
+		if err := checkAndFlush(accountHash[:]); err != nil {
 			return err
 		}
 		// If the iterated account is the contract, create a further loop to