diff --git a/services/java/com/android/server/MountService.java b/services/java/com/android/server/MountService.java
index 32ab154..ba758e5 100644
--- a/services/java/com/android/server/MountService.java
+++ b/services/java/com/android/server/MountService.java
@@ -549,34 +549,6 @@
         }
     }
 
-    private final BroadcastReceiver mBootReceiver = new BroadcastReceiver() {
-        @Override
-        public void onReceive(Context context, Intent intent) {
-            final int userId = intent.getIntExtra(Intent.EXTRA_USER_HANDLE, -1);
-            if (userId == -1) return;
-            final UserHandle user = new UserHandle(userId);
-
-            Slog.d(TAG, "BOOT_COMPLETED for " + user);
-
-            // Broadcast mounted volumes to newly booted user. This kicks off
-            // media scanner when a user becomes active.
-            synchronized (mVolumesLock) {
-                for (StorageVolume volume : mVolumes) {
-                    final UserHandle owner = volume.getOwner();
-                    final boolean ownerMatch = owner == null
-                            || owner.getIdentifier() == user.getIdentifier();
-
-                    final String state = mVolumeStates.get(volume.getPath());
-
-                    if (ownerMatch && (Environment.MEDIA_MOUNTED.equals(state)
-                            || Environment.MEDIA_MOUNTED_READ_ONLY.equals(state))) {
-                        sendStorageIntent(Intent.ACTION_MEDIA_MOUNTED, volume, user);
-                    }
-                }
-            }
-        }
-    };
-
     private final BroadcastReceiver mUserReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
@@ -1309,10 +1281,6 @@
         mHandlerThread.start();
         mHandler = new MountServiceHandler(mHandlerThread.getLooper());
 
-        // Watch for user boot completion
-        mContext.registerReceiverAsUser(mBootReceiver, UserHandle.ALL,
-                new IntentFilter(Intent.ACTION_BOOT_COMPLETED), null, mHandler);
-
         // Watch for user changes
         final IntentFilter userFilter = new IntentFilter();
         userFilter.addAction(Intent.ACTION_USER_ADDED);
diff --git a/services/java/com/android/server/am/ActivityManagerService.java b/services/java/com/android/server/am/ActivityManagerService.java
index ce5424b..55dcc65 100644
--- a/services/java/com/android/server/am/ActivityManagerService.java
+++ b/services/java/com/android/server/am/ActivityManagerService.java
@@ -14224,12 +14224,14 @@
 
     @Override
     public UserInfo getCurrentUser() {
-        if (checkCallingPermission(android.Manifest.permission.INTERACT_ACROSS_USERS_FULL)
-                != PackageManager.PERMISSION_GRANTED) {
+        if ((checkCallingPermission(android.Manifest.permission.INTERACT_ACROSS_USERS)
+                != PackageManager.PERMISSION_GRANTED) && (
+                checkCallingPermission(android.Manifest.permission.INTERACT_ACROSS_USERS_FULL)
+                != PackageManager.PERMISSION_GRANTED)) {
             String msg = "Permission Denial: getCurrentUser() from pid="
                     + Binder.getCallingPid()
                     + ", uid=" + Binder.getCallingUid()
-                    + " requires " + android.Manifest.permission.INTERACT_ACROSS_USERS_FULL;
+                    + " requires " + android.Manifest.permission.INTERACT_ACROSS_USERS;
             Slog.w(TAG, msg);
             throw new SecurityException(msg);
         }
diff --git a/services/java/com/android/server/pm/UserManagerService.java b/services/java/com/android/server/pm/UserManagerService.java
index be86628..2dc9a6a 100644
--- a/services/java/com/android/server/pm/UserManagerService.java
+++ b/services/java/com/android/server/pm/UserManagerService.java
@@ -39,6 +39,7 @@
 import android.os.Process;
 import android.os.RemoteException;
 import android.os.UserHandle;
+import android.os.UserManager;
 import android.util.AtomicFile;
 import android.util.Slog;
 import android.util.SparseArray;
@@ -85,8 +86,6 @@
 
     private SparseArray<UserInfo> mUsers = new SparseArray<UserInfo>();
 
-    private final int mUserLimit;
-
     private int[] mUserIds;
     private boolean mGuestEnabled;
     private int mNextSerialNumber;
@@ -129,8 +128,6 @@
             mPm = pm;
             mInstallLock = installLock;
             mPackagesLock = packagesLock;
-            mUserLimit = mContext.getResources().getInteger(
-                    com.android.internal.R.integer.config_multiuserMaximumUsers);
             mUsersDir = new File(dataDir, USER_INFO_DIR);
             mUsersDir.mkdirs();
             // Make zeroth user directory, for services to migrate their files to that location
@@ -275,7 +272,7 @@
      */
     private boolean isUserLimitReachedLocked() {
         int nUsers = mUsers.size();
-        return nUsers >= mUserLimit;
+        return nUsers >= UserManager.getMaxSupportedUsers();
     }
 
     /**
diff --git a/services/java/com/android/server/usb/UsbDeviceManager.java b/services/java/com/android/server/usb/UsbDeviceManager.java
index 3ef6d4c..392d5e7 100644
--- a/services/java/com/android/server/usb/UsbDeviceManager.java
+++ b/services/java/com/android/server/usb/UsbDeviceManager.java
@@ -91,6 +91,7 @@
     private static final int MSG_SET_CURRENT_FUNCTIONS = 2;
     private static final int MSG_SYSTEM_READY = 3;
     private static final int MSG_BOOT_COMPLETED = 4;
+    private static final int MSG_USER_SWITCHED = 5;
 
     private static final int AUDIO_MODE_NONE = 0;
     private static final int AUDIO_MODE_SOURCE = 1;
@@ -295,14 +296,24 @@
         private UsbAccessory mCurrentAccessory;
         private int mUsbNotificationId;
         private boolean mAdbNotificationShown;
+        private int mCurrentUser = UserHandle.USER_NULL;
 
         private final BroadcastReceiver mBootCompletedReceiver = new BroadcastReceiver() {
+            @Override
             public void onReceive(Context context, Intent intent) {
                 if (DEBUG) Slog.d(TAG, "boot completed");
                 mHandler.sendEmptyMessage(MSG_BOOT_COMPLETED);
             }
         };
 
+        private final BroadcastReceiver mUserSwitchedReceiver = new BroadcastReceiver() {
+            @Override
+            public void onReceive(Context context, Intent intent) {
+                final int userId = intent.getIntExtra(Intent.EXTRA_USER_HANDLE, -1);
+                mHandler.obtainMessage(MSG_USER_SWITCHED, userId, 0).sendToTarget();
+            }
+        };
+
         public UsbHandler(Looper looper) {
             super(looper);
             try {
@@ -347,8 +358,10 @@
                 mUEventObserver.startObserving(USB_STATE_MATCH);
                 mUEventObserver.startObserving(ACCESSORY_START_MATCH);
 
-                mContext.registerReceiver(mBootCompletedReceiver,
-                        new IntentFilter(Intent.ACTION_BOOT_COMPLETED));
+                mContext.registerReceiver(
+                        mBootCompletedReceiver, new IntentFilter(Intent.ACTION_BOOT_COMPLETED));
+                mContext.registerReceiver(
+                        mUserSwitchedReceiver, new IntentFilter(Intent.ACTION_USER_SWITCHED));
             } catch (Exception e) {
                 Slog.e(TAG, "Error initializing UsbHandler", e);
             }
@@ -611,6 +624,18 @@
                         mDebuggingManager.setAdbEnabled(mAdbEnabled);
                     }
                     break;
+                case MSG_USER_SWITCHED: {
+                    final boolean mtpActive =
+                            containsFunction(mCurrentFunctions, UsbManager.USB_FUNCTION_MTP)
+                            || containsFunction(mCurrentFunctions, UsbManager.USB_FUNCTION_PTP);
+                    if (mtpActive && mCurrentUser != UserHandle.USER_NULL) {
+                        Slog.v(TAG, "Current user switched; resetting USB host stack for MTP");
+                        setUsbConfig("none");
+                        setUsbConfig(mCurrentFunctions);
+                    }
+                    mCurrentUser = msg.arg1;
+                    break;
+                }
             }
         }