enable GRO in syscall tests

GRO should be totally transparent and should not affect behavior.

PiperOrigin-RevId: 518424809

runsc/boot/network.go

@@ -121,17 +121,19 @@ type XDPLink struct {
 	LinkAddress       net.HardwareAddr
 	QDisc             config.QueueingDiscipline
 	Neighbors         []Neighbor
+	GvisorGROTimeout  time.Duration
 
 	// NumChannels controls how many underlying FDs are to be used to
 	// create this endpoint.
 	NumChannels int
 }
 
-// LoopbackLink configures a loopback li nk.
+// LoopbackLink configures a loopback link.
 type LoopbackLink struct {
-	Name      string
-	Addresses []IPWithPrefix
-	Routes    []Route
+	Name             string
+	Addresses        []IPWithPrefix
+	Routes           []Route
+	GvisorGROTimeout time.Duration
 }
 
 // CreateLinksAndRoutesArgs are arguments to CreateLinkAndRoutes.
@@ -216,7 +218,10 @@ func (n *Network) CreateLinksAndRoutes(args *CreateLinksAndRoutesArgs, _ *struct
 		linkEP := packetsocket.New(ethernet.New(loopback.New()))
 
 		log.Infof("Enabling loopback interface %q with id %d on addresses %+v", link.Name, nicID, link.Addresses)
-		opts := stack.NICOptions{Name: link.Name}
+		opts := stack.NICOptions{
+			Name:       link.Name,
+			GROTimeout: link.GvisorGROTimeout,
+		}
 		if err := n.createNICWithAddrs(nicID, linkEP, opts, link.Addresses); err != nil {
 			return err
 		}
@@ -383,8 +388,9 @@ func (n *Network) CreateLinksAndRoutes(args *CreateLinksAndRoutesArgs, _ *struct
 
 		log.Infof("Enabling interface %q with id %d on addresses %+v (%v) w/ %d channels", link.Name, nicID, link.Addresses, mac, link.NumChannels)
 		opts := stack.NICOptions{
-			Name:  link.Name,
-			QDisc: qDisc,
+			Name:       link.Name,
+			QDisc:      qDisc,
+			GROTimeout: link.GvisorGROTimeout,
 		}
 		if err := n.createNICWithAddrs(nicID, sniffEP, opts, link.Addresses); err != nil {
 			return err

runsc/sandbox/network.go

@@ -60,7 +60,7 @@ func setupNetwork(conn *urpc.Client, pid int, conf *config.Config) error {
 	switch conf.Network {
 	case config.NetworkNone:
 		log.Infof("Network is disabled, create loopback interface only")
-		if err := createDefaultLoopbackInterface(conn); err != nil {
+		if err := createDefaultLoopbackInterface(conf, conn); err != nil {
 			return fmt.Errorf("creating default loopback interface: %v", err)
 		}
 	case config.NetworkSandbox:
@@ -78,9 +78,11 @@ func setupNetwork(conn *urpc.Client, pid int, conf *config.Config) error {
 	return nil
 }
 
-func createDefaultLoopbackInterface(conn *urpc.Client) error {
+func createDefaultLoopbackInterface(conf *config.Config, conn *urpc.Client) error {
+	link := boot.DefaultLoopbackLink
+	link.GvisorGROTimeout = conf.GvisorGROTimeout
 	if err := conn.Call(boot.NetworkCreateLinksAndRoutes, &boot.CreateLinksAndRoutesArgs{
-		LoopbackLinks: []boot.LoopbackLink{boot.DefaultLoopbackLink},
+		LoopbackLinks: []boot.LoopbackLink{link},
 	}, nil); err != nil {
 		return fmt.Errorf("creating loopback link and routes: %v", err)
 	}
@@ -157,7 +159,7 @@ func createInterfacesAndRoutesFromNS(conn *urpc.Client, nsPath string, conf *con
 
 		// We build our own loopback device.
 		if iface.Flags&net.FlagLoopback != 0 {
-			link, err := loopbackLink(iface, allAddrs)
+			link, err := loopbackLink(conf, iface, allAddrs)
 			if err != nil {
 				return fmt.Errorf("getting loopback link for iface %q: %w", iface.Name, err)
 			}
@@ -261,6 +263,7 @@ func createInterfacesAndRoutesFromNS(conn *urpc.Client, nsPath string, conf *con
 				Neighbors:         neighbors,
 				LinkAddress:       linkAddress,
 				Addresses:         addresses,
+				GvisorGROTimeout:  conf.GvisorGROTimeout,
 			})
 		} else {
 			link := boot.FDBasedLink{
@@ -492,9 +495,10 @@ func createSocketXDP(iface net.Interface) ([]*os.File, error) {
 
 // loopbackLink returns the link with addresses and routes for a loopback
 // interface.
-func loopbackLink(iface net.Interface, addrs []net.Addr) (boot.LoopbackLink, error) {
+func loopbackLink(conf *config.Config, iface net.Interface, addrs []net.Addr) (boot.LoopbackLink, error) {
 	link := boot.LoopbackLink{
-		Name: iface.Name,
+		Name:             iface.Name,
+		GvisorGROTimeout: conf.GvisorGROTimeout,
 	}
 	for _, addr := range addrs {
 		ipNet, ok := addr.(*net.IPNet)

test/runner/main.go

@@ -229,6 +229,7 @@ func runRunsc(tc *gtest.TestCase, spec *specs.Spec) error {
 		"-watchdog-action=panic",
 		"-platform", *platform,
 		"-file-access", *fileAccess,
+		"-gvisor-gro=200000ns",
 	}
 
 	if *network == "host" && !testutil.TestEnvSupportsRawSockets {