diff --git a/core/lib/Drupal/Core/Entity/ContentEntityForm.php b/core/lib/Drupal/Core/Entity/ContentEntityForm.php
index bca3c33..2c1604b 100644
--- a/core/lib/Drupal/Core/Entity/ContentEntityForm.php
+++ b/core/lib/Drupal/Core/Entity/ContentEntityForm.php
@@ -135,10 +135,11 @@ protected function getEditedFieldNames(FormStateInterface $form_state) {
   protected function flagViolations(EntityConstraintViolationListInterface $violations, array $form, FormStateInterface $form_state) {
     // Flag entity level violations.
     foreach ($violations->getEntityViolations() as $violation) {
-      $form_state->setErrorByName('', $violation);
+      /** @var \Symfony\Component\Validator\ConstraintViolationInterface $violation */
+      $form_state->setErrorByName('', $violation->getMessage());
     }
     // Let the form display flag violations of its fields.
-    $this->getFormDisplay($form_state)->flagViolations($violations, $form, $form_state);
+    $this->getFormDisplay($form_state)->flagWidgetsErrorsFromViolations($violations, $form, $form_state);
   }
 
   /**
diff --git a/core/lib/Drupal/Core/Entity/Display/EntityFormDisplayInterface.php b/core/lib/Drupal/Core/Entity/Display/EntityFormDisplayInterface.php
index 345a0bf..b71b0ec 100644
--- a/core/lib/Drupal/Core/Entity/Display/EntityFormDisplayInterface.php
+++ b/core/lib/Drupal/Core/Entity/Display/EntityFormDisplayInterface.php
@@ -179,6 +179,6 @@ public function validateFormValues(FieldableEntityInterface $entity, array &$for
    * @param \Drupal\Core\Form\FormStateInterface $form_state
    *   The form state.
    */
-  public function flagViolations(EntityConstraintViolationListInterface $violations, array &$form, FormStateInterface $form_state);
+  public function flagWidgetsErrorsFromViolations(EntityConstraintViolationListInterface $violations, array &$form, FormStateInterface $form_state);
 
 }
diff --git a/core/lib/Drupal/Core/Entity/Entity/EntityFormDisplay.php b/core/lib/Drupal/Core/Entity/Entity/EntityFormDisplay.php
index 20e978c..2af89b5 100644
--- a/core/lib/Drupal/Core/Entity/Entity/EntityFormDisplay.php
+++ b/core/lib/Drupal/Core/Entity/Entity/EntityFormDisplay.php
@@ -243,16 +243,17 @@ public function validateFormValues(FieldableEntityInterface $entity, array &$for
 
     // Flag entity level violations.
     foreach ($violations->getEntityViolations() as $violation) {
-      $form_state->setErrorByName('', $violation);
+      /** @var \Symfony\Component\Validator\ConstraintViolationInterface $violation */
+      $form_state->setErrorByName('', $violation->getMessage());
     }
 
-    $this->flagViolations($violations, $form, $form_state);
+    $this->flagWidgetsErrorsFromViolations($violations, $form, $form_state);
   }
 
   /**
    * {@inheritdoc}
    */
-  public function flagViolations(EntityConstraintViolationListInterface $violations, array &$form, FormStateInterface $form_state) {
+  public function flagWidgetsErrorsFromViolations(EntityConstraintViolationListInterface $violations, array &$form, FormStateInterface $form_state) {
     $entity = $violations->getEntity();
     foreach ($violations->getFieldNames() as $field_name) {
       // Only show violations for fields that actually appear in the form, and
diff --git a/core/lib/Drupal/Core/Entity/EntityConstraintViolationList.php b/core/lib/Drupal/Core/Entity/EntityConstraintViolationList.php
index 26a0046..507975c 100644
--- a/core/lib/Drupal/Core/Entity/EntityConstraintViolationList.php
+++ b/core/lib/Drupal/Core/Entity/EntityConstraintViolationList.php
@@ -90,7 +90,7 @@ public function getEntityViolations() {
     foreach ($this->entityViolationOffsets as $offset) {
       $violations[] = $this->get($offset);
     }
-    return new static($this->entity,$violations);
+    return new static($this->entity, $violations);
   }
 
   /**
@@ -131,16 +131,15 @@ public function filterByFields(array $field_names) {
           // Keep the composite field if it covers some remaining field and put
           // a violation on some other covered field instead.
           if ($remaining_fields = array_diff($covered_fields, $field_names)) {
-            $message_template = 'The validation failed because the value conflicts with the value in %field_name, which you cannot access.';
             $message_params = ['%field_name' => $field_name];
             $violation = new ConstraintViolation(
-              $this->t($message_template, $message_params),
-              $message_template,
+              $this->t('The validation failed because the value conflicts with the value in %field_name, which you cannot access.', $message_params),
+              'The validation failed because the value conflicts with the value in %field_name, which you cannot access.',
               $message_params,
               $violation->getRoot(),
               reset($remaining_fields),
               $violation->getInvalidValue(),
-              $violation->getMessagePluralization(),
+              $violation->getPlural(),
               $violation->getCode(),
               $violation->getConstraint(),
               $violation->getCause()
diff --git a/core/lib/Drupal/Core/Entity/EntityConstraintViolationListInterface.php b/core/lib/Drupal/Core/Entity/EntityConstraintViolationListInterface.php
index acf62f3..4231790 100644
--- a/core/lib/Drupal/Core/Entity/EntityConstraintViolationListInterface.php
+++ b/core/lib/Drupal/Core/Entity/EntityConstraintViolationListInterface.php
@@ -23,7 +23,7 @@
    * Gets violations flagged on entity level, not associated with any field.
    *
    * @return \Drupal\Core\Entity\EntityConstraintViolationListInterface
-   *   A list of violations of the given fields.
+   *   A list of violations on the entity level.
    */
   public function getEntityViolations();
 
@@ -53,7 +53,9 @@ public function getByField($field_name);
   public function getByFields(array $field_names);
 
   /**
-   * Filters the violations by the given fields.
+   * Filters this violation list by the given fields.
+   *
+   * The returned object just has violations attached to the provided fields.
    *
    * When violations should be displayed for a sub-set of visible fields only,
    * this method may be used to filter the set of visible violations first.
@@ -66,10 +68,10 @@ public function getByFields(array $field_names);
   public function filterByFields(array $field_names);
 
   /**
-   * Filters the violations to apply for accessible fields only.
+   * Filters this violation list to apply for accessible fields only.
    *
-   * Violations for inaccessible fields are skipped and remaining violations
-   * are returned.
+   * Violations for inaccessible fields are removed so the returned object just
+   * has the remaining violations.
    *
    * @param \Drupal\Core\Session\AccountInterface $account
    *   (optional) The user for which to check access, or NULL to check access
diff --git a/core/modules/system/src/Tests/Entity/FieldWidgetConstraintValidatorTest.php b/core/modules/system/src/Tests/Entity/FieldWidgetConstraintValidatorTest.php
index b0b3474..5f36973 100644
--- a/core/modules/system/src/Tests/Entity/FieldWidgetConstraintValidatorTest.php
+++ b/core/modules/system/src/Tests/Entity/FieldWidgetConstraintValidatorTest.php
@@ -138,4 +138,17 @@ public function testValidationWithCompositeConstraint() {
     $this->assertEqual($errors['type'], SafeMarkup::format('The validation failed because the value conflicts with the value in %field_name, which you cannot access.', ['%field_name' => 'name']));
   }
 
+  /**
+   * Tests entity level constraint validation.
+   */
+  public function testEntityLevelConstraintValidation() {
+    $entity = EntityTestCompositeConstraint::create([
+      'name' => 'entity-level-violation'
+    ]);
+    $entity->save();
+
+    $errors = $this->getErrorsForEntity($entity);
+    $this->assertEqual($errors[''], 'Entity level validation');
+  }
+
 }
diff --git a/core/modules/system/tests/modules/entity_test/src/Entity/EntityTestCompositeConstraint.php b/core/modules/system/tests/modules/entity_test/src/Entity/EntityTestCompositeConstraint.php
index 1085c92..e092c1c 100644
--- a/core/modules/system/tests/modules/entity_test/src/Entity/EntityTestCompositeConstraint.php
+++ b/core/modules/system/tests/modules/entity_test/src/Entity/EntityTestCompositeConstraint.php
@@ -29,6 +29,7 @@
  *   persistent_cache = FALSE,
  *   constraints = {
  *     "EntityTestComposite" = {},
+ *     "EntityTestEntityLevel" = {},
  *   }
  * )
  */
diff --git a/core/modules/system/tests/modules/entity_test/src/Plugin/Validation/Constraint/EntityTestEntityLevel.php b/core/modules/system/tests/modules/entity_test/src/Plugin/Validation/Constraint/EntityTestEntityLevel.php
new file mode 100644
index 0000000..ec647bd
--- /dev/null
+++ b/core/modules/system/tests/modules/entity_test/src/Plugin/Validation/Constraint/EntityTestEntityLevel.php
@@ -0,0 +1,25 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Plugin\Validation\Constraint\EntityTestEntityLevel.
+ */
+
+namespace Drupal\entity_test\Plugin\Validation\Constraint;
+
+use Symfony\Component\Validator\Constraint;
+
+/**
+ * Constraint on entity entity level.
+ *
+ * @Plugin(
+ *   id = "EntityTestEntityLevel",
+ *   label = @Translation("Constraint on the entity level."),
+ *   type = "entity"
+ * )
+ */
+class EntityTestEntityLevel extends Constraint {
+
+  public $message = 'Entity level validation';
+
+}
diff --git a/core/modules/system/tests/modules/entity_test/src/Plugin/Validation/Constraint/EntityTestEntityLevelValidator.php b/core/modules/system/tests/modules/entity_test/src/Plugin/Validation/Constraint/EntityTestEntityLevelValidator.php
new file mode 100644
index 0000000..78d8785
--- /dev/null
+++ b/core/modules/system/tests/modules/entity_test/src/Plugin/Validation/Constraint/EntityTestEntityLevelValidator.php
@@ -0,0 +1,35 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Plugin\Validation\Constraint\EntityTestEntityLevelValidator.
+ */
+
+namespace Drupal\entity_test\Plugin\Validation\Constraint;
+
+use Symfony\Component\Validator\Constraint;
+use Symfony\Component\Validator\ConstraintValidator;
+
+/**
+ * Constraint validator for the EntityTestEntityLevel constraint.
+ */
+class EntityTestEntityLevelValidator extends ConstraintValidator {
+
+  /**
+   * Validator 2.5 and upwards compatible execution context.
+   *
+   * @var \Symfony\Component\Validator\Context\ExecutionContextInterface
+   */
+  protected $context;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validate($value, Constraint $constraint) {
+    if ($value->name->value === 'entity-level-violation') {
+      $this->context->buildViolation($constraint->message)
+        ->addViolation();
+    }
+  }
+
+}