diff --git a/virtualizationservice/aidl/Android.bp b/virtualizationservice/aidl/Android.bp
index 30a4b03..4d5326a 100644
--- a/virtualizationservice/aidl/Android.bp
+++ b/virtualizationservice/aidl/Android.bp
@@ -5,6 +5,7 @@
 aidl_interface {
     name: "android.system.virtualizationservice",
     srcs: ["android/system/virtualizationservice/**/*.aidl"],
+    imports: ["android.system.virtualizationcommon"],
     // This is never accessed directly. Apps are expected to use this indirectly via the Java
     // wrapper android.system.virtualmachine.
     unstable: true,
@@ -35,6 +36,7 @@
 aidl_interface {
     name: "android.system.virtualmachineservice",
     srcs: ["android/system/virtualmachineservice/**/*.aidl"],
+    imports: ["android.system.virtualizationcommon"],
     unstable: true,
     backend: {
         rust: {
@@ -46,3 +48,27 @@
         },
     },
 }
+
+aidl_interface {
+    name: "android.system.virtualizationcommon",
+    srcs: ["android/system/virtualizationcommon/**/*.aidl"],
+    unstable: true,
+    backend: {
+        java: {
+            apex_available: ["com.android.virt"],
+        },
+        ndk: {
+            apex_available: [
+                "com.android.virt",
+                "com.android.compos",
+            ],
+        },
+        rust: {
+            enabled: true,
+            apex_available: [
+                "com.android.virt",
+                "com.android.compos",
+            ],
+        },
+    },
+}
diff --git a/virtualizationservice/aidl/android/system/virtualizationcommon/ErrorCode.aidl b/virtualizationservice/aidl/android/system/virtualizationcommon/ErrorCode.aidl
new file mode 100644
index 0000000..04b9749
--- /dev/null
+++ b/virtualizationservice/aidl/android/system/virtualizationcommon/ErrorCode.aidl
@@ -0,0 +1,43 @@
+/*
+ * Copyright 2022 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 android.system.virtualizationcommon;
+
+/**
+ * Errors reported from within a VM.
+ */
+@Backing(type="int")
+enum ErrorCode {
+    /**
+     * Error code for all other errors not listed below.
+     */
+    UNKNOWN = 0,
+
+    /**
+     * Error code indicating that the payload can't be verified due to various reasons (e.g invalid
+     * merkle tree, invalid formats, etc).
+     */
+    PAYLOAD_VERIFICATION_FAILED = 1,
+
+    /**
+     * Error code indicating that the payload is verified, but has changed since the last boot.
+     */
+    PAYLOAD_CHANGED = 2,
+
+    /**
+     * Error code indicating that the payload config is invalid.
+     */
+    PAYLOAD_CONFIG_INVALID = 3,
+}
diff --git a/virtualizationservice/aidl/android/system/virtualizationservice/IVirtualMachineCallback.aidl b/virtualizationservice/aidl/android/system/virtualizationservice/IVirtualMachineCallback.aidl
index 6c8eb4a..8d6ed08 100644
--- a/virtualizationservice/aidl/android/system/virtualizationservice/IVirtualMachineCallback.aidl
+++ b/virtualizationservice/aidl/android/system/virtualizationservice/IVirtualMachineCallback.aidl
@@ -15,6 +15,7 @@
  */
 package android.system.virtualizationservice;
 
+import android.system.virtualizationcommon.ErrorCode;
 import android.system.virtualizationservice.DeathReason;
 
 /**
@@ -44,7 +45,7 @@
     /**
      * Called when an error occurs in the VM.
      */
-    void onError(int cid, int errorCode, in String message);
+    void onError(int cid, ErrorCode errorCode, in String message);
 
     /**
      * Called when the VM dies.
diff --git a/virtualizationservice/aidl/android/system/virtualizationservice/VirtualMachineAppConfig.aidl b/virtualizationservice/aidl/android/system/virtualizationservice/VirtualMachineAppConfig.aidl
index 8eb5497..d86f2bf 100644
--- a/virtualizationservice/aidl/android/system/virtualizationservice/VirtualMachineAppConfig.aidl
+++ b/virtualizationservice/aidl/android/system/virtualizationservice/VirtualMachineAppConfig.aidl
@@ -48,7 +48,7 @@
     }
 
     /** Debug level of the VM */
-    DebugLevel debugLevel;
+    DebugLevel debugLevel = DebugLevel.NONE;
 
     /** Whether the VM should be a protected VM. */
     boolean protectedVm;
diff --git a/virtualizationservice/aidl/android/system/virtualizationservice/VirtualMachineDebugInfo.aidl b/virtualizationservice/aidl/android/system/virtualizationservice/VirtualMachineDebugInfo.aidl
index 672c41a..bed4097 100644
--- a/virtualizationservice/aidl/android/system/virtualizationservice/VirtualMachineDebugInfo.aidl
+++ b/virtualizationservice/aidl/android/system/virtualizationservice/VirtualMachineDebugInfo.aidl
@@ -38,5 +38,5 @@
     int requesterPid;
 
     /** The current lifecycle state of the VM. */
-    VirtualMachineState state;
+    VirtualMachineState state = VirtualMachineState.NOT_STARTED;
 }
diff --git a/virtualizationservice/aidl/android/system/virtualmachineservice/IVirtualMachineService.aidl b/virtualizationservice/aidl/android/system/virtualmachineservice/IVirtualMachineService.aidl
index dff5d46..e8c1724 100644
--- a/virtualizationservice/aidl/android/system/virtualmachineservice/IVirtualMachineService.aidl
+++ b/virtualizationservice/aidl/android/system/virtualmachineservice/IVirtualMachineService.aidl
@@ -15,6 +15,8 @@
  */
 package android.system.virtualmachineservice;
 
+import android.system.virtualizationcommon.ErrorCode;
+
 /** {@hide} */
 interface IVirtualMachineService {
     /**
@@ -51,28 +53,7 @@
     void notifyPayloadFinished(int exitCode);
 
     /**
-     * Notifies that an error has occurred. See the ERROR_* constants.
+     * Notifies that an error has occurred inside the VM..
      */
-    void notifyError(int errorCode, in String message);
-
-    /**
-     * Error code for all other errors not listed below.
-     */
-    const int ERROR_UNKNOWN = 0;
-
-    /**
-     * Error code indicating that the payload can't be verified due to various reasons (e.g invalid
-     * merkle tree, invalid formats, etc).
-     */
-    const int ERROR_PAYLOAD_VERIFICATION_FAILED = 1;
-
-    /**
-     * Error code indicating that the payload is verified, but has changed since the last boot.
-     */
-    const int ERROR_PAYLOAD_CHANGED = 2;
-
-    /**
-     * Error code indicating that the payload config is invalid.
-     */
-    const int ERROR_PAYLOAD_INVALID_CONFIG = 3;
+    void notifyError(ErrorCode errorCode, in String message);
 }