diff --git a/packages/SystemUI/src/com/android/systemui/qs/QuickQSPanelController.java b/packages/SystemUI/src/com/android/systemui/qs/QuickQSPanelController.java
index ac85ca4dda636..cca0e1b0c0f0d 100644
--- a/packages/SystemUI/src/com/android/systemui/qs/QuickQSPanelController.java
+++ b/packages/SystemUI/src/com/android/systemui/qs/QuickQSPanelController.java
@@ -40,8 +40,6 @@ import javax.inject.Named;
 @QSScope
 public class QuickQSPanelController extends QSPanelControllerBase<QuickQSPanel> {
 
-    private List<QSTile> mAllTiles = new ArrayList<>();
-
     private final QSPanel.OnConfigurationChangedListener mOnConfigurationChangedListener =
             newConfig -> {
                 int newMaxTiles = getResources().getInteger(R.integer.quick_qs_panel_max_columns);
@@ -92,14 +90,14 @@ public class QuickQSPanelController extends QSPanelControllerBase<QuickQSPanel>
 
     @Override
     public void setTiles() {
-        mAllTiles.clear();
+        List<QSTile> tiles = new ArrayList();
         for (QSTile tile : mHost.getTiles()) {
-            mAllTiles.add(tile);
-            if (mAllTiles.size() == QuickQSPanel.DEFAULT_MAX_TILES) {
+            tiles.add(tile);
+            if (tiles.size() == mView.getNumQuickTiles()) {
                 break;
             }
         }
-        super.setTiles(mAllTiles.subList(0, mView.getNumQuickTiles()), true);
+        super.setTiles(tiles, true);
     }
 
     /** */
diff --git a/packages/SystemUI/tests/src/com/android/systemui/qs/QuickQSPanelControllerTest.kt b/packages/SystemUI/tests/src/com/android/systemui/qs/QuickQSPanelControllerTest.kt
new file mode 100644
index 0000000000000..3f2b4da764e34
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/qs/QuickQSPanelControllerTest.kt
@@ -0,0 +1,111 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.qs
+
+import android.testing.AndroidTestingRunner
+import androidx.test.filters.SmallTest
+import com.android.internal.logging.MetricsLogger
+import com.android.internal.logging.testing.UiEventLoggerFake
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.dump.DumpManager
+import com.android.systemui.media.MediaHost
+import com.android.systemui.plugins.qs.QSTile
+import com.android.systemui.qs.customize.QSCustomizerController
+import com.android.systemui.qs.logging.QSLogger
+import org.junit.After
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.Mock
+import org.mockito.Mockito.`when`
+import org.mockito.Mockito.any
+import org.mockito.Mockito.times
+import org.mockito.Mockito.verify
+import org.mockito.MockitoAnnotations
+
+@SmallTest
+@RunWith(AndroidTestingRunner::class)
+class QuickQSPanelControllerTest : SysuiTestCase() {
+
+    @Mock
+    private lateinit var quickQSPanel: QuickQSPanel
+    @Mock
+    private lateinit var qsTileHost: QSTileHost
+    @Mock
+    private lateinit var qsCustomizerController: QSCustomizerController
+    @Mock
+    private lateinit var mediaHost: MediaHost
+    @Mock
+    private lateinit var metricsLogger: MetricsLogger
+    private val uiEventLogger = UiEventLoggerFake()
+    @Mock
+    private lateinit var qsLogger: QSLogger
+    private val dumpManager = DumpManager()
+    @Mock
+    private lateinit var tile: QSTile
+    @Mock
+    private lateinit var tileLayout: TileLayout
+
+    private lateinit var controller: QuickQSPanelController
+
+    @Before
+    fun setUp() {
+        MockitoAnnotations.initMocks(this)
+
+        `when`(quickQSPanel.tileLayout).thenReturn(tileLayout)
+        `when`(quickQSPanel.dumpableTag).thenReturn("")
+
+        controller = QuickQSPanelController(
+                quickQSPanel,
+                qsTileHost,
+                qsCustomizerController,
+                false,
+                mediaHost,
+                metricsLogger,
+                uiEventLogger,
+                qsLogger,
+                dumpManager
+        )
+
+        controller.init()
+    }
+
+    @After
+    fun tearDown() {
+        controller.onViewDetached()
+    }
+
+    @Test
+    fun testTileSublistWithFewerTiles_noCrash() {
+        `when`(quickQSPanel.numQuickTiles).thenReturn(3)
+
+        `when`(qsTileHost.tiles).thenReturn(listOf(tile, tile))
+
+        controller.setTiles()
+    }
+
+    @Test
+    fun testTileSublistWithTooManyTiles() {
+        val limit = 3
+        `when`(quickQSPanel.numQuickTiles).thenReturn(limit)
+        `when`(qsTileHost.tiles).thenReturn(listOf(tile, tile, tile, tile))
+
+        controller.setTiles()
+
+        verify(quickQSPanel, times(limit)).addTile(any())
+    }
+}
\ No newline at end of file