diff --git a/core/java/android/os/PersistableBundle.java b/core/java/android/os/PersistableBundle.java
index 02704f5..236194d 100644
--- a/core/java/android/os/PersistableBundle.java
+++ b/core/java/android/os/PersistableBundle.java
@@ -294,6 +294,43 @@
         XmlUtils.writeMapXml(mMap, out, this);
     }
 
+    /**
+     * Checks whether all keys and values are within the given character limit.
+     * Note: Maximum character limit of String that can be saved to XML as part of bundle is 65535.
+     * Otherwise IOException is thrown.
+     * @param limit length of String keys and values in the PersistableBundle, including nested
+     *                    PersistableBundles to check against.
+     *
+     * @hide
+     */
+    public boolean isBundleContentsWithinLengthLimit(int limit) {
+        unparcel();
+        if (mMap == null) {
+            return true;
+        }
+        for (int i = 0; i < mMap.size(); i++) {
+            if (mMap.keyAt(i) != null && mMap.keyAt(i).length() > limit) {
+                return false;
+            }
+            final Object value = mMap.valueAt(i);
+            if (value instanceof String && ((String) value).length() > limit) {
+                return false;
+            } else if (value instanceof String[]) {
+                String[] stringArray =  (String[]) value;
+                for (int j = 0; j < stringArray.length; j++) {
+                    if (stringArray[j] != null
+                            && stringArray[j].length() > limit) {
+                        return false;
+                    }
+                }
+            } else if (value instanceof PersistableBundle
+                    && !((PersistableBundle) value).isBundleContentsWithinLengthLimit(limit)) {
+                return false;
+            }
+        }
+        return true;
+    }
+
     /** @hide */
     static class MyReadMapCallback implements  XmlUtils.ReadMapCallback {
         @Override
diff --git a/core/java/android/os/UserManager.java b/core/java/android/os/UserManager.java
index 683bc31..7a7c667 100644
--- a/core/java/android/os/UserManager.java
+++ b/core/java/android/os/UserManager.java
@@ -104,6 +104,21 @@
     /** Whether the device is in headless system user mode; null until cached. */
     private static Boolean sIsHeadlessSystemUser = null;
 
+    /** Maximum length of username.
+     * @hide
+     */
+    public static final int MAX_USER_NAME_LENGTH = 100;
+
+    /** Maximum length of user property String value.
+     * @hide
+     */
+    public static final int MAX_ACCOUNT_STRING_LENGTH = 500;
+
+    /** Maximum length of account options String values.
+     * @hide
+     */
+    public static final int MAX_ACCOUNT_OPTIONS_LENGTH = 1000;
+
     /**
      * User type representing a {@link UserHandle#USER_SYSTEM system} user that is a human user.
      * This type of user cannot be created; it can only pre-exist on first boot.
@@ -4205,15 +4220,15 @@
      * This API should only be called if the current user is an {@link #isAdminUser() admin} user,
      * as otherwise the returned intent will not be able to create a user.
      *
-     * @param userName Optional name to assign to the user.
+     * @param userName Optional name to assign to the user. Character limit is 100.
      * @param accountName Optional account name that will be used by the setup wizard to initialize
-     *                    the user.
+     *                    the user. Character limit is 500.
      * @param accountType Optional account type for the account to be created. This is required
-     *                    if the account name is specified.
+     *                    if the account name is specified. Character limit is 500.
      * @param accountOptions Optional bundle of data to be passed in during account creation in the
      *                       new user via {@link AccountManager#addAccount(String, String, String[],
      *                       Bundle, android.app.Activity, android.accounts.AccountManagerCallback,
-     *                       Handler)}.
+     *                       Handler)}. Character limit is 1000.
      * @return An Intent that can be launched from an Activity.
      * @see #USER_CREATION_FAILED_NOT_PERMITTED
      * @see #USER_CREATION_FAILED_NO_MORE_USERS
diff --git a/core/java/com/android/internal/app/ConfirmUserCreationActivity.java b/core/java/com/android/internal/app/ConfirmUserCreationActivity.java
index 0a28997..b4e8749 100644
--- a/core/java/com/android/internal/app/ConfirmUserCreationActivity.java
+++ b/core/java/com/android/internal/app/ConfirmUserCreationActivity.java
@@ -116,6 +116,14 @@
         if (cantCreateUser) {
             setResult(UserManager.USER_CREATION_FAILED_NOT_PERMITTED);
             return null;
+        } else if (!(isUserPropertyWithinLimit(mUserName, UserManager.MAX_USER_NAME_LENGTH)
+                && isUserPropertyWithinLimit(mAccountName, UserManager.MAX_ACCOUNT_STRING_LENGTH)
+                && isUserPropertyWithinLimit(mAccountType, UserManager.MAX_ACCOUNT_STRING_LENGTH))
+                || (mAccountOptions != null && !mAccountOptions.isBundleContentsWithinLengthLimit(
+                UserManager.MAX_ACCOUNT_OPTIONS_LENGTH))) {
+            setResult(UserManager.USER_CREATION_FAILED_NOT_PERMITTED);
+            Log.i(TAG, "User properties must not exceed their character limits");
+            return null;
         } else if (cantCreateAnyMoreUsers) {
             setResult(UserManager.USER_CREATION_FAILED_NO_MORE_USERS);
             return null;
@@ -144,4 +152,8 @@
         }
         finish();
     }
+
+    private boolean isUserPropertyWithinLimit(String property, int limit) {
+        return property == null || property.length() <= limit;
+    }
 }
diff --git a/libs/WindowManager/Shell/Android.bp b/libs/WindowManager/Shell/Android.bp
index 54978bd..e1c095b 100644
--- a/libs/WindowManager/Shell/Android.bp
+++ b/libs/WindowManager/Shell/Android.bp
@@ -165,7 +165,7 @@
         // *.kt sources are inside a filegroup.
         "kotlin-annotations",
     ],
-    kotlincflags: ["-Xjvm-default=enable"],
+    kotlincflags: ["-Xjvm-default=all"],
     manifest: "AndroidManifest.xml",
     plugins: ["dagger2-compiler"],
 }
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/common/FloatingContentCoordinator.kt b/libs/WindowManager/Shell/src/com/android/wm/shell/common/FloatingContentCoordinator.kt
index d5d072a..122dcbb 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/common/FloatingContentCoordinator.kt
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/common/FloatingContentCoordinator.kt
@@ -94,7 +94,6 @@
          * non-overlapping.
          * @return The new bounds for this content.
          */
-        @JvmDefault
         fun calculateNewBoundsOnOverlap(
             overlappingContentBounds: Rect,
             otherContentBounds: List<Rect>
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeTaskRepository.kt b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeTaskRepository.kt
index 3ab175d..a7a1991 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeTaskRepository.kt
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeTaskRepository.kt
@@ -318,7 +318,6 @@
         /**
          * Called when the active tasks change in desktop mode.
          */
-        @JvmDefault
         fun onActiveTasksChanged(displayId: Int) {}
     }
 
@@ -329,7 +328,6 @@
         /**
          * Called when the desktop starts or stops showing freeform tasks.
          */
-        @JvmDefault
         fun onVisibilityChanged(displayId: Int, hasVisibleFreeformTasks: Boolean) {}
     }
 }
diff --git a/libs/WindowManager/Shell/tests/unittest/Android.bp b/libs/WindowManager/Shell/tests/unittest/Android.bp
index ad4d97f..38e9f39 100644
--- a/libs/WindowManager/Shell/tests/unittest/Android.bp
+++ b/libs/WindowManager/Shell/tests/unittest/Android.bp
@@ -61,7 +61,7 @@
         "libstaticjvmtiagent",
     ],
 
-    kotlincflags: ["-Xjvm-default=enable"],
+    kotlincflags: ["-Xjvm-default=all"],
 
     plugins: ["dagger2-compiler"],
 
diff --git a/packages/CredentialManager/Android.bp b/packages/CredentialManager/Android.bp
index 28b9bc0..fe26dc3 100644
--- a/packages/CredentialManager/Android.bp
+++ b/packages/CredentialManager/Android.bp
@@ -44,7 +44,7 @@
     platform_apis: true,
     privileged: true,
 
-    kotlincflags: ["-Xjvm-default=enable"],
+    kotlincflags: ["-Xjvm-default=all"],
 
     optimize: {
         proguard_compatibility: false,
diff --git a/packages/EasterEgg/Android.bp b/packages/EasterEgg/Android.bp
index 8699f59..0caf505 100644
--- a/packages/EasterEgg/Android.bp
+++ b/packages/EasterEgg/Android.bp
@@ -70,5 +70,5 @@
 
     manifest: "AndroidManifest.xml",
 
-    kotlincflags: ["-Xjvm-default=enable"],
+    kotlincflags: ["-Xjvm-default=all"],
 }
diff --git a/packages/SystemUI/Android.bp b/packages/SystemUI/Android.bp
index 7df3dfb..8fe3824 100644
--- a/packages/SystemUI/Android.bp
+++ b/packages/SystemUI/Android.bp
@@ -201,7 +201,7 @@
     manifest: "AndroidManifest.xml",
 
     javacflags: ["-Adagger.fastInit=enabled"],
-    kotlincflags: ["-Xjvm-default=enable"],
+    kotlincflags: ["-Xjvm-default=all"],
 
     plugins: ["dagger2-compiler"],
 
@@ -393,7 +393,7 @@
         "android.test.base",
         "android.test.mock",
     ],
-    kotlincflags: ["-Xjvm-default=enable"],
+    kotlincflags: ["-Xjvm-default=all"],
     aaptflags: [
         "--extra-packages",
         "com.android.systemui",
@@ -515,7 +515,7 @@
     certificate: "platform",
     privileged: true,
 
-    kotlincflags: ["-Xjvm-default=enable"],
+    kotlincflags: ["-Xjvm-default=all"],
 
     dxflags: ["--multi-dex"],
     optimize: {
diff --git a/packages/SystemUI/animation/src/com/android/systemui/animation/ActivityLaunchAnimator.kt b/packages/SystemUI/animation/src/com/android/systemui/animation/ActivityLaunchAnimator.kt
index 764a855..8306620 100644
--- a/packages/SystemUI/animation/src/com/android/systemui/animation/ActivityLaunchAnimator.kt
+++ b/packages/SystemUI/animation/src/com/android/systemui/animation/ActivityLaunchAnimator.kt
@@ -302,10 +302,9 @@
 
     interface Callback {
         /** Whether we are currently on the keyguard or not. */
-        @JvmDefault fun isOnKeyguard(): Boolean = false
+        fun isOnKeyguard(): Boolean = false
 
         /** Hide the keyguard and animate using [runner]. */
-        @JvmDefault
         fun hideKeyguardWithAnimation(runner: IRemoteAnimationRunner) {
             throw UnsupportedOperationException()
         }
@@ -316,16 +315,16 @@
 
     interface Listener {
         /** Called when an activity launch animation started. */
-        @JvmDefault fun onLaunchAnimationStart() {}
+        fun onLaunchAnimationStart() {}
 
         /**
          * Called when an activity launch animation is finished. This will be called if and only if
          * [onLaunchAnimationStart] was called earlier.
          */
-        @JvmDefault fun onLaunchAnimationEnd() {}
+        fun onLaunchAnimationEnd() {}
 
         /** Called when an activity launch animation made progress. */
-        @JvmDefault fun onLaunchAnimationProgress(linearProgress: Float) {}
+        fun onLaunchAnimationProgress(linearProgress: Float) {}
     }
 
     /**
diff --git a/packages/SystemUI/compose/core/tests/Android.bp b/packages/SystemUI/compose/core/tests/Android.bp
index 6119e96..06d94ac 100644
--- a/packages/SystemUI/compose/core/tests/Android.bp
+++ b/packages/SystemUI/compose/core/tests/Android.bp
@@ -44,5 +44,5 @@
         "androidx.compose.ui_ui-test-manifest",
     ],
 
-    kotlincflags: ["-Xjvm-default=enable"],
+    kotlincflags: ["-Xjvm-default=all"],
 }
diff --git a/packages/SystemUI/compose/features/tests/Android.bp b/packages/SystemUI/compose/features/tests/Android.bp
index ff534bd..c7c9140 100644
--- a/packages/SystemUI/compose/features/tests/Android.bp
+++ b/packages/SystemUI/compose/features/tests/Android.bp
@@ -44,5 +44,5 @@
         "androidx.compose.ui_ui-test-manifest",
     ],
 
-    kotlincflags: ["-Xjvm-default=enable"],
+    kotlincflags: ["-Xjvm-default=all"],
 }
diff --git a/packages/SystemUI/customization/Android.bp b/packages/SystemUI/customization/Android.bp
index dc450bb..fc37b355 100644
--- a/packages/SystemUI/customization/Android.bp
+++ b/packages/SystemUI/customization/Android.bp
@@ -48,5 +48,5 @@
     ],
     min_sdk_version: "current",
     plugins: ["dagger2-compiler"],
-    kotlincflags: ["-Xjvm-default=enable"],
+    kotlincflags: ["-Xjvm-default=all"],
 }
diff --git a/packages/SystemUI/shared/Android.bp b/packages/SystemUI/shared/Android.bp
index 28e786b..ca30e15 100644
--- a/packages/SystemUI/shared/Android.bp
+++ b/packages/SystemUI/shared/Android.bp
@@ -65,7 +65,7 @@
     ],
     min_sdk_version: "current",
     plugins: ["dagger2-compiler"],
-    kotlincflags: ["-Xjvm-default=enable"],
+    kotlincflags: ["-Xjvm-default=all"],
 }
 
 java_library {
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/KeyguardUnlockAnimationController.kt b/packages/SystemUI/src/com/android/systemui/keyguard/KeyguardUnlockAnimationController.kt
index 68e72c5..ff39034 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/KeyguardUnlockAnimationController.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/KeyguardUnlockAnimationController.kt
@@ -171,7 +171,6 @@
          * for the canned animation (if applicable) so interested parties can sync with it. If no
          * canned animation is playing, these are both 0.
          */
-        @JvmDefault
         fun onUnlockAnimationStarted(
             playingCannedAnimation: Boolean,
             isWakeAndUnlockNotFromDream: Boolean,
@@ -184,7 +183,6 @@
          * The keyguard is no longer visible in this state and the app/launcher behind the keyguard
          * is now completely visible.
          */
-        @JvmDefault
         fun onUnlockAnimationFinished() {}
     }
 
diff --git a/packages/SystemUI/src/com/android/systemui/privacy/PrivacyConfig.kt b/packages/SystemUI/src/com/android/systemui/privacy/PrivacyConfig.kt
index d652889..d949a2a 100644
--- a/packages/SystemUI/src/com/android/systemui/privacy/PrivacyConfig.kt
+++ b/packages/SystemUI/src/com/android/systemui/privacy/PrivacyConfig.kt
@@ -145,13 +145,10 @@
     }
 
     interface Callback {
-        @JvmDefault
         fun onFlagMicCameraChanged(flag: Boolean) {}
 
-        @JvmDefault
         fun onFlagLocationChanged(flag: Boolean) {}
 
-        @JvmDefault
         fun onFlagMediaProjectionChanged(flag: Boolean) {}
     }
 }
\ No newline at end of file
diff --git a/packages/SystemUI/src/com/android/systemui/privacy/PrivacyItemController.kt b/packages/SystemUI/src/com/android/systemui/privacy/PrivacyItemController.kt
index a676150..eb8ef9b 100644
--- a/packages/SystemUI/src/com/android/systemui/privacy/PrivacyItemController.kt
+++ b/packages/SystemUI/src/com/android/systemui/privacy/PrivacyItemController.kt
@@ -216,7 +216,6 @@
     interface Callback : PrivacyConfig.Callback {
         fun onPrivacyItemsChanged(privacyItems: List<PrivacyItem>)
 
-        @JvmDefault
         fun onFlagAllChanged(flag: Boolean) {}
     }
 
diff --git a/packages/SystemUI/src/com/android/systemui/settings/DisplayTracker.kt b/packages/SystemUI/src/com/android/systemui/settings/DisplayTracker.kt
index bb7f721..468a75d 100644
--- a/packages/SystemUI/src/com/android/systemui/settings/DisplayTracker.kt
+++ b/packages/SystemUI/src/com/android/systemui/settings/DisplayTracker.kt
@@ -52,12 +52,12 @@
     interface Callback {
 
         /** Notifies that a display has been added. */
-        @JvmDefault fun onDisplayAdded(displayId: Int) {}
+        fun onDisplayAdded(displayId: Int) {}
 
         /** Notifies that a display has been removed. */
-        @JvmDefault fun onDisplayRemoved(displayId: Int) {}
+        fun onDisplayRemoved(displayId: Int) {}
 
         /** Notifies a display has been changed */
-        @JvmDefault fun onDisplayChanged(displayId: Int) {}
+        fun onDisplayChanged(displayId: Int) {}
     }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/settings/UserTracker.kt b/packages/SystemUI/src/com/android/systemui/settings/UserTracker.kt
index 33a3125..93a3e90 100644
--- a/packages/SystemUI/src/com/android/systemui/settings/UserTracker.kt
+++ b/packages/SystemUI/src/com/android/systemui/settings/UserTracker.kt
@@ -71,7 +71,6 @@
          * Same as {@link onUserChanging(Int, Context, CountDownLatch)} but the latch will be
          * auto-decremented after the completion of this method.
          */
-        @JvmDefault
         fun onUserChanging(newUser: Int, userContext: Context) {}
 
         /**
@@ -82,7 +81,6 @@
          * user switch duration. When overriding this method, countDown() MUST be called on the
          * latch once execution is complete.
          */
-        @JvmDefault
         fun onUserChanging(newUser: Int, userContext: Context, latch: CountDownLatch) {
             onUserChanging(newUser, userContext)
             latch.countDown()
@@ -93,13 +91,11 @@
          * Override this method to run things after the screen is unfrozen for the user switch.
          * Please see {@link #onUserChanging} if you need to hide jank.
          */
-        @JvmDefault
         fun onUserChanged(newUser: Int, userContext: Context) {}
 
         /**
          * Notifies that the current user's profiles have changed.
          */
-        @JvmDefault
         fun onProfilesChanged(profiles: List<@JvmSuppressWildcards UserInfo>) {}
     }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/shade/ShadeStateEvents.kt b/packages/SystemUI/src/com/android/systemui/shade/ShadeStateEvents.kt
index 56bb1a6..5804040 100644
--- a/packages/SystemUI/src/com/android/systemui/shade/ShadeStateEvents.kt
+++ b/packages/SystemUI/src/com/android/systemui/shade/ShadeStateEvents.kt
@@ -29,12 +29,12 @@
     interface ShadeStateEventsListener {
 
         /** Invoked when the notification panel starts or stops collapsing. */
-        @JvmDefault fun onPanelCollapsingChanged(isCollapsing: Boolean) {}
+        fun onPanelCollapsingChanged(isCollapsing: Boolean) {}
 
         /**
          * Invoked when the notification panel starts or stops launching an [android.app.Activity].
          */
-        @JvmDefault fun onLaunchingActivityChanged(isLaunchingActivity: Boolean) {}
+        fun onLaunchingActivityChanged(isLaunchingActivity: Boolean) {}
 
         /**
          * Invoked when the "expand immediate" attribute changes.
@@ -45,6 +45,6 @@
          * Another example is when full QS is showing, and we swipe up from the bottom. Instead of
          * going to QQS, the panel fully collapses.
          */
-        @JvmDefault fun onExpandImmediateChanged(isExpandImmediateEnabled: Boolean) {}
+        fun onExpandImmediateChanged(isExpandImmediateEnabled: Boolean) {}
     }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/NotificationShadeDepthController.kt b/packages/SystemUI/src/com/android/systemui/statusbar/NotificationShadeDepthController.kt
index 0e20df6..b624115 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/NotificationShadeDepthController.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/NotificationShadeDepthController.kt
@@ -553,7 +553,6 @@
          */
         fun onWallpaperZoomOutChanged(zoomOut: Float)
 
-        @JvmDefault
         fun onBlurRadiusChanged(blurRadius: Int) {}
     }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/connectivity/SignalCallback.kt b/packages/SystemUI/src/com/android/systemui/statusbar/connectivity/SignalCallback.kt
index 599beec..6be407a 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/connectivity/SignalCallback.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/connectivity/SignalCallback.kt
@@ -29,7 +29,6 @@
      *
      * @param wifiIndicators a box type containing enough information to properly draw a Wi-Fi icon
      */
-    @JvmDefault
     fun setWifiIndicators(wifiIndicators: WifiIndicators) {}
 
     /**
@@ -42,7 +41,6 @@
      * NOTE: phones can have multiple subscriptions, so this [mobileDataIndicators] object should be
      * indexed based on its [subId][MobileDataIndicators.subId]
      */
-    @JvmDefault
     fun setMobileDataIndicators(mobileDataIndicators: MobileDataIndicators) {}
 
     /**
@@ -51,7 +49,6 @@
      *
      * @param subs a [SubscriptionInfo] for each subscription that we know about
      */
-    @JvmDefault
     fun setSubs(subs: List<@JvmSuppressWildcards SubscriptionInfo>) {}
 
     /**
@@ -63,7 +60,6 @@
      * @param show whether or not to show a "no sim" view
      * @param simDetected whether any SIM is detected or not
      */
-    @JvmDefault
     fun setNoSims(show: Boolean, simDetected: Boolean) {}
 
     /**
@@ -72,7 +68,6 @@
      *
      * @param icon an [IconState] for the current ethernet status
      */
-    @JvmDefault
     fun setEthernetIndicators(icon: IconState) {}
 
     /**
@@ -80,7 +75,6 @@
      *
      * @param icon an [IconState] for the current airplane mode status
      */
-    @JvmDefault
     fun setIsAirplaneMode(icon: IconState) {}
 
     /**
@@ -88,7 +82,6 @@
      *
      * @param enabled the current mobile data feature ennabled state
      */
-    @JvmDefault
     fun setMobileDataEnabled(enabled: Boolean) {}
 
     /**
@@ -97,7 +90,6 @@
      * @param noValidatedNetwork whether there is any validated network.
      * @param noNetworksAvailable whether there is any WiFi networks available.
      */
-    @JvmDefault
     fun setConnectivityStatus(
         noDefaultNetwork: Boolean,
         noValidatedNetwork: Boolean,
@@ -109,7 +101,6 @@
      * @param statusIcon the icon for the call indicator
      * @param subId subscription ID for which to update the UI
      */
-    @JvmDefault
     fun setCallIndicator(statusIcon: IconState, subId: Int) {}
 }
 
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/events/SystemStatusAnimationScheduler.kt b/packages/SystemUI/src/com/android/systemui/statusbar/events/SystemStatusAnimationScheduler.kt
index 2a18f1f..ef90890 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/events/SystemStatusAnimationScheduler.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/events/SystemStatusAnimationScheduler.kt
@@ -49,11 +49,10 @@
     fun onSystemEventAnimationFinish(hasPersistentDot: Boolean): Animator? { return null }
 
     // Best method name, change my mind
-    @JvmDefault
     fun onSystemStatusAnimationTransitionToPersistentDot(contentDescription: String?): Animator? {
         return null
     }
-    @JvmDefault fun onHidePersistentDot(): Animator? { return null }
+    fun onHidePersistentDot(): Animator? { return null }
 }
 
 
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/notification/NotificationWakeUpCoordinator.kt b/packages/SystemUI/src/com/android/systemui/statusbar/notification/NotificationWakeUpCoordinator.kt
index 9ba2199..8d1e8d0 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/notification/NotificationWakeUpCoordinator.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/notification/NotificationWakeUpCoordinator.kt
@@ -613,20 +613,20 @@
 
     interface WakeUpListener {
         /** Called whenever the notifications are fully hidden or shown */
-        @JvmDefault fun onFullyHiddenChanged(isFullyHidden: Boolean) {}
+        fun onFullyHiddenChanged(isFullyHidden: Boolean) {}
 
         /**
          * Called whenever the pulseExpansion changes
          *
          * @param expandingChanged if the user has started or stopped expanding
          */
-        @JvmDefault fun onPulseExpansionChanged(expandingChanged: Boolean) {}
+        fun onPulseExpansionChanged(expandingChanged: Boolean) {}
 
         /**
          * Called when the animator started by [scheduleDelayedDozeAmountAnimation] begins running
          * after the start delay, or after it ends/is cancelled.
          */
-        @JvmDefault fun onDelayedDozeAmountAnimationRunning(running: Boolean) {}
+        fun onDelayedDozeAmountAnimationRunning(running: Boolean) {}
     }
 
     companion object {
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/notification/Roundable.kt b/packages/SystemUI/src/com/android/systemui/statusbar/notification/Roundable.kt
index 212f2c215..087383a 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/notification/Roundable.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/notification/Roundable.kt
@@ -22,33 +22,27 @@
 
     /** Current top roundness */
     @get:FloatRange(from = 0.0, to = 1.0)
-    @JvmDefault
     val topRoundness: Float
         get() = roundableState.topRoundness
 
     /** Current bottom roundness */
     @get:FloatRange(from = 0.0, to = 1.0)
-    @JvmDefault
     val bottomRoundness: Float
         get() = roundableState.bottomRoundness
 
     /** Max radius in pixel */
-    @JvmDefault
     val maxRadius: Float
         get() = roundableState.maxRadius
 
     /** Current top corner in pixel, based on [topRoundness] and [maxRadius] */
-    @JvmDefault
     val topCornerRadius: Float
         get() = topRoundness * maxRadius
 
     /** Current bottom corner in pixel, based on [bottomRoundness] and [maxRadius] */
-    @JvmDefault
     val bottomCornerRadius: Float
         get() = bottomRoundness * maxRadius
 
     /** Get and update the current radii */
-    @JvmDefault
     val updatedRadii: FloatArray
         get() =
             roundableState.radiiBuffer.also { radii ->
@@ -71,7 +65,6 @@
      * @param sourceType the source from which the request for roundness comes.
      * @return Whether the roundness was changed.
      */
-    @JvmDefault
     fun requestTopRoundness(
         @FloatRange(from = 0.0, to = 1.0) value: Float,
         sourceType: SourceType,
@@ -116,7 +109,6 @@
      * @param sourceType the source from which the request for roundness comes.
      * @return Whether the roundness was changed.
      */
-    @JvmDefault
     fun requestTopRoundness(
         @FloatRange(from = 0.0, to = 1.0) value: Float,
         sourceType: SourceType,
@@ -140,7 +132,6 @@
      * @param sourceType the source from which the request for roundness comes.
      * @return Whether the roundness was changed.
      */
-    @JvmDefault
     fun requestBottomRoundness(
         @FloatRange(from = 0.0, to = 1.0) value: Float,
         sourceType: SourceType,
@@ -185,7 +176,6 @@
      * @param sourceType the source from which the request for roundness comes.
      * @return Whether the roundness was changed.
      */
-    @JvmDefault
     fun requestBottomRoundness(
         @FloatRange(from = 0.0, to = 1.0) value: Float,
         sourceType: SourceType,
@@ -210,7 +200,6 @@
      * @param animate true if it should animate to that value.
      * @return Whether the roundness was changed.
      */
-    @JvmDefault
     fun requestRoundness(
         @FloatRange(from = 0.0, to = 1.0) top: Float,
         @FloatRange(from = 0.0, to = 1.0) bottom: Float,
@@ -237,7 +226,6 @@
      * @param sourceType the source from which the request for roundness comes.
      * @return Whether the roundness was changed.
      */
-    @JvmDefault
     fun requestRoundness(
         @FloatRange(from = 0.0, to = 1.0) top: Float,
         @FloatRange(from = 0.0, to = 1.0) bottom: Float,
@@ -261,7 +249,6 @@
      * @param sourceType the source from which the request for roundness comes.
      * @param animate true if it should animate to that value.
      */
-    @JvmDefault
     fun requestRoundnessReset(sourceType: SourceType, animate: Boolean) {
         requestRoundness(top = 0f, bottom = 0f, sourceType = sourceType, animate = animate)
     }
@@ -275,19 +262,16 @@
      *
      * @param sourceType the source from which the request for roundness comes.
      */
-    @JvmDefault
     fun requestRoundnessReset(sourceType: SourceType) {
         requestRoundnessReset(sourceType = sourceType, animate = roundableState.targetView.isShown)
     }
 
     /** Apply the roundness changes, usually means invalidate the [RoundableState.targetView]. */
-    @JvmDefault
     fun applyRoundnessAndInvalidate() {
         roundableState.targetView.invalidate()
     }
 
     /** @return true if top or bottom roundness is not zero. */
-    @JvmDefault
     fun hasRoundedCorner(): Boolean {
         return topRoundness != 0f || bottomRoundness != 0f
     }
@@ -298,7 +282,6 @@
      *
      * This method reuses the previous [radii] for performance reasons.
      */
-    @JvmDefault
     fun updateRadii(
         topCornerRadius: Float,
         bottomCornerRadius: Float,
diff --git a/packages/SystemUI/src/com/android/systemui/util/UserAwareController.kt b/packages/SystemUI/src/com/android/systemui/util/UserAwareController.kt
index 693c270..5582ced 100644
--- a/packages/SystemUI/src/com/android/systemui/util/UserAwareController.kt
+++ b/packages/SystemUI/src/com/android/systemui/util/UserAwareController.kt
@@ -23,7 +23,6 @@
  * changes.
  */
 interface UserAwareController {
-    @JvmDefault
     fun changeUser(newUser: UserHandle) {}
 
     val currentUserId: Int
diff --git a/packages/SystemUI/unfold/Android.bp b/packages/SystemUI/unfold/Android.bp
index 2e0a946..1f0181f 100644
--- a/packages/SystemUI/unfold/Android.bp
+++ b/packages/SystemUI/unfold/Android.bp
@@ -33,7 +33,7 @@
         "dagger2",
         "jsr330",
     ],
-    kotlincflags: ["-Xjvm-default=enable"],
+    kotlincflags: ["-Xjvm-default=all"],
     java_version: "1.8",
     sdk_version: "current",
     min_sdk_version: "current",
diff --git a/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldTransitionProgressProvider.kt b/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldTransitionProgressProvider.kt
index fee485d..896444d 100644
--- a/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldTransitionProgressProvider.kt
+++ b/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldTransitionProgressProvider.kt
@@ -35,14 +35,12 @@
 
     interface TransitionProgressListener {
         /** Called when transition is started */
-        @JvmDefault
         fun onTransitionStarted() {}
 
         /**
          * Called whenever transition progress is updated, [progress] is a value of the animation
          * where 0 is fully folded, 1 is fully unfolded
          */
-        @JvmDefault
         fun onTransitionProgress(@FloatRange(from = 0.0, to = 1.0) progress: Float) {}
 
         /**
@@ -51,11 +49,9 @@
          * For example, in [PhysicsBasedUnfoldTransitionProgressProvider] this could happen when the
          * animation is not tied to the hinge angle anymore and it is about to run fixed animation.
          */
-        @JvmDefault
         fun onTransitionFinishing() {}
 
         /** Called when transition is completely finished */
-        @JvmDefault
         fun onTransitionFinished() {}
     }
 }
diff --git a/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/FoldStateProvider.kt b/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/FoldStateProvider.kt
index 0af372f..bce7e88 100644
--- a/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/FoldStateProvider.kt
+++ b/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/FoldStateProvider.kt
@@ -31,9 +31,9 @@
     val isFinishedOpening: Boolean
 
     interface FoldUpdatesListener {
-        @JvmDefault fun onHingeAngleUpdate(@FloatRange(from = 0.0, to = 180.0) angle: Float) {}
-        @JvmDefault fun onFoldUpdate(@FoldUpdate update: Int) {}
-        @JvmDefault fun onUnfoldedScreenAvailable() {}
+        fun onHingeAngleUpdate(@FloatRange(from = 0.0, to = 180.0) angle: Float) {}
+        fun onFoldUpdate(@FoldUpdate update: Int) {}
+        fun onUnfoldedScreenAvailable() {}
     }
 
     @IntDef(
diff --git a/services/core/java/com/android/server/pm/UserManagerService.java b/services/core/java/com/android/server/pm/UserManagerService.java
index ffb4cb3..03231472d 100644
--- a/services/core/java/com/android/server/pm/UserManagerService.java
+++ b/services/core/java/com/android/server/pm/UserManagerService.java
@@ -284,8 +284,6 @@
 
     private static final int USER_VERSION = 11;
 
-    private static final int MAX_USER_STRING_LENGTH = 500;
-
     private static final long EPOCH_PLUS_30_YEARS = 30L * 365 * 24 * 60 * 60 * 1000L; // ms
 
     static final int WRITE_USER_MSG = 1;
@@ -4274,16 +4272,18 @@
         if (userData.persistSeedData) {
             if (userData.seedAccountName != null) {
                 serializer.attribute(null, ATTR_SEED_ACCOUNT_NAME,
-                        truncateString(userData.seedAccountName));
+                        truncateString(userData.seedAccountName,
+                                UserManager.MAX_ACCOUNT_STRING_LENGTH));
             }
             if (userData.seedAccountType != null) {
                 serializer.attribute(null, ATTR_SEED_ACCOUNT_TYPE,
-                        truncateString(userData.seedAccountType));
+                        truncateString(userData.seedAccountType,
+                                UserManager.MAX_ACCOUNT_STRING_LENGTH));
             }
         }
         if (userInfo.name != null) {
             serializer.startTag(null, TAG_NAME);
-            serializer.text(truncateString(userInfo.name));
+            serializer.text(truncateString(userInfo.name, UserManager.MAX_USER_NAME_LENGTH));
             serializer.endTag(null, TAG_NAME);
         }
         synchronized (mRestrictionsLock) {
@@ -4332,11 +4332,11 @@
         serializer.endDocument();
     }
 
-    private String truncateString(String original) {
-        if (original == null || original.length() <= MAX_USER_STRING_LENGTH) {
+    private String truncateString(String original, int limit) {
+        if (original == null || original.length() <= limit) {
             return original;
         }
-        return original.substring(0, MAX_USER_STRING_LENGTH);
+        return original.substring(0, limit);
     }
 
     /*
@@ -4784,8 +4784,7 @@
             @UserIdInt int parentId, boolean preCreate, @Nullable String[] disallowedPackages,
             @NonNull TimingsTraceAndSlog t, @Nullable Object token)
             throws UserManager.CheckedUserOperationException {
-
-        String truncatedName = truncateString(name);
+        String truncatedName = truncateString(name, UserManager.MAX_USER_NAME_LENGTH);
         final UserTypeDetails userTypeDetails = mUserTypes.get(userType);
         if (userTypeDetails == null) {
             throwCheckedUserOperationException(
@@ -6386,9 +6385,14 @@
                     Slog.e(LOG_TAG, "No such user for settings seed data u=" + userId);
                     return;
                 }
-                userData.seedAccountName = truncateString(accountName);
-                userData.seedAccountType = truncateString(accountType);
-                userData.seedAccountOptions = accountOptions;
+                userData.seedAccountName = truncateString(accountName,
+                        UserManager.MAX_ACCOUNT_STRING_LENGTH);
+                userData.seedAccountType = truncateString(accountType,
+                        UserManager.MAX_ACCOUNT_STRING_LENGTH);
+                if (accountOptions != null && accountOptions.isBundleContentsWithinLengthLimit(
+                        UserManager.MAX_ACCOUNT_OPTIONS_LENGTH)) {
+                    userData.seedAccountOptions = accountOptions;
+                }
                 userData.persistSeedData = persist;
             }
             if (persist) {
diff --git a/services/tests/mockingservicestests/src/com/android/server/pm/UserManagerServiceTest.java b/services/tests/mockingservicestests/src/com/android/server/pm/UserManagerServiceTest.java
index c8ff758..5f18e9e 100644
--- a/services/tests/mockingservicestests/src/com/android/server/pm/UserManagerServiceTest.java
+++ b/services/tests/mockingservicestests/src/com/android/server/pm/UserManagerServiceTest.java
@@ -331,7 +331,7 @@
     @Test
     public void testCreateUserWithLongName_TruncatesName() {
         UserInfo user = mUms.createUserWithThrow(generateLongString(), USER_TYPE_FULL_SECONDARY, 0);
-        assertThat(user.name.length()).isEqualTo(500);
+        assertThat(user.name.length()).isEqualTo(UserManager.MAX_USER_NAME_LENGTH);
         UserInfo user1 = mUms.createUserWithThrow("Test", USER_TYPE_FULL_SECONDARY, 0);
         assertThat(user1.name.length()).isEqualTo(4);
     }
diff --git a/services/tests/servicestests/src/com/android/server/pm/UserManagerTest.java b/services/tests/servicestests/src/com/android/server/pm/UserManagerTest.java
index e511c79..48f36f8 100644
--- a/services/tests/servicestests/src/com/android/server/pm/UserManagerTest.java
+++ b/services/tests/servicestests/src/com/android/server/pm/UserManagerTest.java
@@ -19,6 +19,7 @@
 import static com.google.common.truth.Truth.assertThat;
 import static com.google.common.truth.Truth.assertWithMessage;
 
+import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 import static org.junit.Assume.assumeTrue;
 import static org.testng.Assert.assertEquals;
@@ -33,6 +34,7 @@
 import android.content.res.Resources;
 import android.graphics.drawable.Drawable;
 import android.os.Bundle;
+import android.os.PersistableBundle;
 import android.os.UserHandle;
 import android.os.UserManager;
 import android.platform.test.annotations.Postsubmit;
@@ -1420,6 +1422,106 @@
         assertThat(userInfo.name).isEqualTo(newName);
     }
 
+    @Test
+    public void testAddUserAccountData_validStringValuesAreSaved_validBundleIsSaved() {
+        assumeManagedUsersSupported();
+
+        String userName = "User";
+        String accountName = "accountName";
+        String accountType = "accountType";
+        String arrayKey = "StringArrayKey";
+        String stringKey = "StringKey";
+        String intKey = "IntKey";
+        String nestedBundleKey = "PersistableBundleKey";
+        String value1 = "Value 1";
+        String value2 = "Value 2";
+        String value3 = "Value 3";
+
+        UserInfo userInfo = mUserManager.createUser(userName,
+                UserManager.USER_TYPE_FULL_SECONDARY, 0);
+
+        PersistableBundle accountOptions = new PersistableBundle();
+        String[] stringArray = {value1, value2};
+        accountOptions.putInt(intKey, 1234);
+        PersistableBundle nested = new PersistableBundle();
+        nested.putString(stringKey, value3);
+        accountOptions.putPersistableBundle(nestedBundleKey, nested);
+        accountOptions.putStringArray(arrayKey, stringArray);
+
+        mUserManager.clearSeedAccountData();
+        mUserManager.setSeedAccountData(mContext.getUserId(), accountName,
+                accountType, accountOptions);
+
+        //assert userName accountName and accountType were saved correctly
+        assertTrue(mUserManager.getUserInfo(userInfo.id).name.equals(userName));
+        assertTrue(mUserManager.getSeedAccountName().equals(accountName));
+        assertTrue(mUserManager.getSeedAccountType().equals(accountType));
+
+        //assert bundle with correct values was added
+        assertThat(mUserManager.getSeedAccountOptions().containsKey(arrayKey)).isTrue();
+        assertThat(mUserManager.getSeedAccountOptions().getPersistableBundle(nestedBundleKey)
+                .getString(stringKey)).isEqualTo(value3);
+        assertThat(mUserManager.getSeedAccountOptions().getStringArray(arrayKey)[0])
+                .isEqualTo(value1);
+
+        mUserManager.removeUser(userInfo.id);
+    }
+
+    @Test
+    public void testAddUserAccountData_invalidStringValuesAreTruncated_invalidBundleIsDropped() {
+        assumeManagedUsersSupported();
+
+        String tooLongString = generateLongString();
+        String userName = "User " + tooLongString;
+        String accountType = "Account Type " + tooLongString;
+        String accountName = "accountName " + tooLongString;
+        String arrayKey = "StringArrayKey";
+        String stringKey = "StringKey";
+        String intKey = "IntKey";
+        String nestedBundleKey = "PersistableBundleKey";
+        String value1 = "Value 1";
+        String value2 = "Value 2";
+
+        UserInfo userInfo = mUserManager.createUser(userName,
+                UserManager.USER_TYPE_FULL_SECONDARY, 0);
+
+        PersistableBundle accountOptions = new PersistableBundle();
+        String[] stringArray = {value1, value2};
+        accountOptions.putInt(intKey, 1234);
+        PersistableBundle nested = new PersistableBundle();
+        nested.putString(stringKey, tooLongString);
+        accountOptions.putPersistableBundle(nestedBundleKey, nested);
+        accountOptions.putStringArray(arrayKey, stringArray);
+        mUserManager.clearSeedAccountData();
+        mUserManager.setSeedAccountData(mContext.getUserId(), accountName,
+                accountType, accountOptions);
+
+        //assert userName was truncated
+        assertTrue(mUserManager.getUserInfo(userInfo.id).name.length()
+                == UserManager.MAX_USER_NAME_LENGTH);
+
+        //assert accountName and accountType got truncated
+        assertTrue(mUserManager.getSeedAccountName().length()
+                == UserManager.MAX_ACCOUNT_STRING_LENGTH);
+        assertTrue(mUserManager.getSeedAccountType().length()
+                == UserManager.MAX_ACCOUNT_STRING_LENGTH);
+
+        //assert bundle with invalid values was dropped
+        assertThat(mUserManager.getSeedAccountOptions() == null).isTrue();
+
+        mUserManager.removeUser(userInfo.id);
+    }
+
+    private String generateLongString() {
+        String partialString = "Test Name Test Name Test Name Test Name Test Name Test Name Test "
+                + "Name Test Name Test Name Test Name "; //String of length 100
+        StringBuilder resultString = new StringBuilder();
+        for (int i = 0; i < 600; i++) {
+            resultString.append(partialString);
+        }
+        return resultString.toString();
+    }
+
     private boolean isPackageInstalledForUser(String packageName, int userId) {
         try {
             return mPackageManager.getPackageInfoAsUser(packageName, 0, userId) != null;