return
	}

	if len(userNs.UIDMappings) != 1 {
		err = fmt.Errorf("invalid user namespace configuration: no more than one mapping allowed.")
		return
	}

	if len(userNs.UIDMappings) != len(userNs.GIDMappings) {
		err = fmt.Errorf("invalid user namespace configuration: GID and UID mappings should be identical.")
		return
	}

	if userNs.UIDMappings[0] != userNs.GIDMappings[0] {

		{
			name: "basic",
			file: `{
	                        "uidMappings":[ { "hostId":131072, "containerId":0, "length":65536 } ],
	                        "gidMappings":[ { "hostId":131072, "containerId":0, "length":65536 } ]
                               }`,
			success: true,
		},
		{
			name: "invalid length",
			file: `{
	                        "uidMappings":[ { "hostId":131072, "containerId":0, "length":0 } ],

		ngroups, groups           uintptr
		c                         uintptr
	)
	pidfd = -1

	rlim := origRlimitNofile.Load()

	if sys.UidMappings != nil {
		puid = []byte("/proc/self/uid_map\000")
		uidmap = formatIDMappings(sys.UidMappings)
	}

	if sys.GidMappings != nil {
		psetgroups = []byte("/proc/self/setgroups\000")
		pgid = []byte("/proc/self/gid_map\000")

		if sys.GidMappingsEnableSetgroups {

pkg syscall (linux-arm), type SysProcIDMap struct
pkg syscall (linux-arm), type SysProcIDMap struct, ContainerID int
pkg syscall (linux-arm), type SysProcIDMap struct, HostID int
pkg syscall (linux-arm), type SysProcIDMap struct, Size int
pkg syscall (linux-arm-cgo), type SysProcAttr struct, GidMappings []SysProcIDMap
pkg syscall (linux-arm-cgo), type SysProcAttr struct, UidMappings []SysProcIDMap

	t.Helper()
	testenv.MustHaveExecPath(t, "whoami")
	cmd := testenv.Command(t, "whoami")
	cmd.SysProcAttr = &syscall.SysProcAttr{
		Cloneflags: syscall.CLONE_NEWUSER,
		UidMappings: []syscall.SysProcIDMap{
			{ContainerID: 0, HostID: uid, Size: 1},
		},
		GidMappings: []syscall.SysProcIDMap{
			{ContainerID: 0, HostID: gid, Size: 1},
		},
		GidMappingsEnableSetgroups: setgroups,
	}
	return cmd
}

		if cl.SecurityContext.NamespaceOptions.UsernsOptions != nil {
			for _, mount := range config.Mounts {
				mount.UidMappings = cl.SecurityContext.NamespaceOptions.UsernsOptions.Uids
				mount.GidMappings = cl.SecurityContext.NamespaceOptions.UsernsOptions.Gids
			}
		}
	}
	return nil
}

// generateLinuxContainerConfig generates linux container config for kubelet runtime v1.

            Optional<PluginImplementation<?>> lookup = uncheckedGet(idMappings, new PluginIdLookupCacheKey(qualified, classLoader));
            if (lookup.isPresent()) {
                return lookup.get();
            }
        }

        return uncheckedGet(idMappings, new PluginIdLookupCacheKey(pluginId, classLoader)).orElse(null);
    }

                // Take a copy because adding to an idMappings value may result in new mappings being added (i.e. ConcurrentModificationException)
                Iterable<PluginId> pluginIds = Lists.newArrayList(idMappings.keySet());
                for (PluginId id : pluginIds) {
                    if (plugin.isAlsoKnownAs(id)) {
                        idMappings.get(id).add(new PluginWithId(id, pluginClass));
                    }

		{"SysProcAttr.Setctty", Field, 0},
		{"SysProcAttr.Setpgid", Field, 0},
		{"SysProcAttr.Setsid", Field, 0},
		{"SysProcAttr.ThreadAttributes", Field, 13},
		{"SysProcAttr.Token", Field, 10},
		{"SysProcAttr.UidMappings", Field, 4},
		{"SysProcAttr.Unshareflags", Field, 7},
		{"SysProcAttr.UseCgroupFD", Field, 20},
		{"SysProcIDMap", Type, 4},
		{"SysProcIDMap.ContainerID", Field, 4},
		{"SysProcIDMap.HostID", Field, 4},