diff --git a/services/core/java/com/android/server/wm/Task.java b/services/core/java/com/android/server/wm/Task.java
index cc72dcfb0be21..3facfd4837c80 100644
--- a/services/core/java/com/android/server/wm/Task.java
+++ b/services/core/java/com/android/server/wm/Task.java
@@ -3766,11 +3766,7 @@ class Task extends WindowContainer<WindowContainer> {
         if (r == null) {
             return null;
         }
-        final Task task = r.getRootTask();
-        if (task != null && r.isDescendantOf(task)) {
-            if (task != this) Slog.w(TAG, "Illegal state! task does not point to stack it is in. "
-                    + "stack=" + this + " task=" + task + " r=" + r
-                    + " callers=" + Debug.getCallers(15, "\n"));
+        if (r.isDescendantOf(this)) {
             return r;
         }
         return null;
diff --git a/services/tests/wmtests/src/com/android/server/wm/TaskTests.java b/services/tests/wmtests/src/com/android/server/wm/TaskTests.java
index 473c1c57d625c..1415c506a1c9f 100644
--- a/services/tests/wmtests/src/com/android/server/wm/TaskTests.java
+++ b/services/tests/wmtests/src/com/android/server/wm/TaskTests.java
@@ -146,4 +146,16 @@ public class TaskTests extends WindowTestsBase {
         task.setBounds(bounds);
         assertEquals(new Point(bounds.left, bounds.top), task.getLastSurfacePosition());
     }
+
+    @Test
+    public void testIsInStack() {
+        final Task task1 = createTaskStackOnDisplay(mDisplayContent);
+        final Task task2 = createTaskStackOnDisplay(mDisplayContent);
+        final ActivityRecord activity1 =
+                WindowTestUtils.createActivityRecordInTask(mDisplayContent, task1);
+        final ActivityRecord activity2 =
+                WindowTestUtils.createActivityRecordInTask(mDisplayContent, task2);
+        assertEquals(activity1, task1.isInTask(activity1));
+        assertNull(task1.isInTask(activity2));
+    }
 }