check region id 0 before retry

store/tikv/coprocessor.go

@@ -849,6 +849,11 @@ func (worker *copIteratorWorker) handleCopStreamResult(bo *Backoffer, rpcCtx *RP
 // successful response, otherwise it's nil.
 func (worker *copIteratorWorker) handleCopResponse(bo *Backoffer, rpcCtx *RPCContext, resp *copResponse, task *copTask, ch chan<- *copResponse, lastRange *coprocessor.KeyRange, costTime time.Duration) ([]*copTask, error) {
 	if regionErr := resp.pbResp.GetRegionError(); regionErr != nil {
+		if rpcCtx.Region.id == 0 {
+			resp.err = errors.Errorf("error: %v", regionErr)
+			worker.sendToRespCh(resp, ch, true)
+			return nil, nil
+		}
 		if err := bo.Backoff(BoRegionMiss, errors.New(regionErr.String())); err != nil {
 			return nil, errors.Trace(err)
 		}

store/tikv/region_request.go

@@ -320,7 +320,9 @@ func (s *RegionRequestSender) onRegionError(bo *Backoffer, ctx *RPCContext, regi
 	logutil.BgLogger().Debug("tikv reports region failed",
 		zap.Stringer("regionErr", regionErr),
 		zap.Stringer("ctx", ctx))
-	s.regionCache.InvalidateCachedRegion(ctx.Region)
+	if ctx.Region.id != 0 {
+		s.regionCache.InvalidateCachedRegion(ctx.Region)
+	}
 	return false, nil
 }