client: fix detection of whether IO was performed in NewStream

internal/transport/http2_client.go

@@ -630,12 +630,17 @@ func (p PerformedIOError) Error() string {
 // NewStream creates a stream and registers it into the transport as "active"
 // streams.
 func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Stream, err error) {
+	defer func() {
+		if err != nil && (len(t.perRPCCreds) > 0 || callHdr.Creds != nil) {
+			// We may have performed I/O in the per-RPC creds callback, so do not
+			// allow transparent retry.
+			err = PerformedIOError{err}
+		}
+	}()
 	ctx = peer.NewContext(ctx, t.getPeer())
 	headerFields, err := t.createHeaderFields(ctx, callHdr)
 	if err != nil {
-		// We may have performed I/O in the per-RPC creds callback, so do not
-		// allow transparent retry.
-		return nil, PerformedIOError{err}
+		return nil, err
 	}
 	s := t.newStream(ctx, callHdr)
 	cleanup := func(err error) {

stream.go

@@ -525,27 +525,33 @@ func (cs *clientStream) commitAttempt() {
 // shouldRetry returns nil if the RPC should be retried; otherwise it returns
 // the error that should be returned by the operation.
 func (cs *clientStream) shouldRetry(err error) error {
-	unprocessed := false
 	if cs.attempt.s == nil {
+		// Error from NewClientStream.
 		pioErr, ok := err.(transport.PerformedIOError)
-		if ok {
-			// Unwrap error.
-			err = toRPCErr(pioErr.Err)
-		} else {
-			unprocessed = true
-		}
-		if !ok && !cs.callInfo.failFast {
+		if !ok {
 			// In the event of a non-IO operation error from NewStream, we
 			// never attempted to write anything to the wire, so we can retry
-			// indefinitely for non-fail-fast RPCs.
+			// indefinitely.  Except for INTERNAL errors, which indicate the
+			// RPC should not be retried due to max header list size violation.
+			if status.Convert(err).Code() == codes.Internal {
+				return err
+			}
 			return nil
 		}
+		// Unwrap error.
+		err = toRPCErr(pioErr.Err)
+		// INTERNAL errors from NewStream indicate the RPC should not be
+		// retried.
+		if status.Convert(err).Code() == codes.Internal {
+			return err
+		}
 	}
 	if cs.finished || cs.committed {
 		// RPC is finished or committed; cannot retry.
 		return err
 	}
 	// Wait for the trailers.
+	unprocessed := false
 	if cs.attempt.s != nil {
 		<-cs.attempt.s.Done()
 		unprocessed = cs.attempt.s.Unprocessed()