diff --git a/pkg/api/errors/errors_test.go b/pkg/api/errors/errors_test.go
index e4743d0d7..2dea0883a 100644
--- a/pkg/api/errors/errors_test.go
+++ b/pkg/api/errors/errors_test.go
@@ -164,7 +164,7 @@ func TestNewInvalid(t *testing.T) {
 			`Kind "name" is invalid: field[0].name: Not found: "bar"`,
 		},
 		{
-			field.NotSupported(field.NewPath("field[0].name"), "bar", nil),
+			field.NotSupported[string](field.NewPath("field[0].name"), "bar", nil),
 			&metav1.StatusDetails{
 				Kind: "Kind",
 				Name: "name",
diff --git a/pkg/util/validation/field/errors.go b/pkg/util/validation/field/errors.go
index ae73bda96..bc387d011 100644
--- a/pkg/util/validation/field/errors.go
+++ b/pkg/util/validation/field/errors.go
@@ -200,12 +200,12 @@ func Invalid(field *Path, value interface{}, detail string) *Error {
 // NotSupported returns a *Error indicating "unsupported value".
 // This is used to report unknown values for enumerated fields (e.g. a list of
 // valid values).
-func NotSupported(field *Path, value interface{}, validValues []string) *Error {
+func NotSupported[T ~string](field *Path, value interface{}, validValues []T) *Error {
 	detail := ""
 	if len(validValues) > 0 {
 		quotedValues := make([]string, len(validValues))
 		for i, v := range validValues {
-			quotedValues[i] = strconv.Quote(v)
+			quotedValues[i] = strconv.Quote(fmt.Sprint(v))
 		}
 		detail = "supported values: " + strings.Join(quotedValues, ", ")
 	}
diff --git a/pkg/util/validation/field/errors_test.go b/pkg/util/validation/field/errors_test.go
index fe747319b..a2f9763b8 100644
--- a/pkg/util/validation/field/errors_test.go
+++ b/pkg/util/validation/field/errors_test.go
@@ -32,7 +32,7 @@ func TestMakeFuncs(t *testing.T) {
 			ErrorTypeInvalid,
 		},
 		{
-			func() *Error { return NotSupported(NewPath("f"), "v", nil) },
+			func() *Error { return NotSupported[string](NewPath("f"), "v", nil) },
 			ErrorTypeNotSupported,
 		},
 		{