diff --git a/METADATA b/METADATA
new file mode 100644
index 0000000..d97975c
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,3 @@
+third_party {
+  license_type: NOTICE
+}
diff --git a/audio/common/all-versions/default/service/android.hardware.audio.service.rc b/audio/common/all-versions/default/service/android.hardware.audio.service.rc
index 63d2542..f7e1e24 100644
--- a/audio/common/all-versions/default/service/android.hardware.audio.service.rc
+++ b/audio/common/all-versions/default/service/android.hardware.audio.service.rc
@@ -5,5 +5,5 @@
     group audio camera drmrpc inet media mediadrm net_bt net_bt_admin net_bw_acct wakelock
     capabilities BLOCK_SUSPEND
     ioprio rt 4
-    writepid /dev/cpuset/foreground/tasks /dev/stune/foreground/tasks
+    task_profiles ProcessCapacityHigh HighPerformance
     onrestart restart audioserver
diff --git a/bluetooth/1.0/default/android.hardware.bluetooth@1.0-service.rc b/bluetooth/1.0/default/android.hardware.bluetooth@1.0-service.rc
index 9fa128d..def59de 100644
--- a/bluetooth/1.0/default/android.hardware.bluetooth@1.0-service.rc
+++ b/bluetooth/1.0/default/android.hardware.bluetooth@1.0-service.rc
@@ -4,5 +4,5 @@
     capabilities BLOCK_SUSPEND NET_ADMIN SYS_NICE
     user bluetooth
     group bluetooth
-    writepid /dev/stune/foreground/tasks
+    task_profiles HighPerformance
 
diff --git a/bluetooth/1.1/default/android.hardware.bluetooth@1.1-service.rc b/bluetooth/1.1/default/android.hardware.bluetooth@1.1-service.rc
index 49f0be3..5c7cbf4 100644
--- a/bluetooth/1.1/default/android.hardware.bluetooth@1.1-service.rc
+++ b/bluetooth/1.1/default/android.hardware.bluetooth@1.1-service.rc
@@ -5,5 +5,5 @@
     capabilities BLOCK_SUSPEND NET_ADMIN SYS_NICE
     user bluetooth
     group bluetooth
-    writepid /dev/stune/foreground/tasks
+    task_profiles HighPerformance
 
diff --git a/camera/provider/2.4/default/android.hardware.camera.provider@2.4-external-service.rc b/camera/provider/2.4/default/android.hardware.camera.provider@2.4-external-service.rc
index 64cf321..52ade97 100644
--- a/camera/provider/2.4/default/android.hardware.camera.provider@2.4-external-service.rc
+++ b/camera/provider/2.4/default/android.hardware.camera.provider@2.4-external-service.rc
@@ -5,4 +5,4 @@
     group audio camera input drmrpc usb
     ioprio rt 4
     capabilities SYS_NICE
-    writepid /dev/cpuset/camera-daemon/tasks /dev/stune/top-app/tasks
+    task_profiles CameraServiceCapacity MaxPerformance
diff --git a/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service-lazy.rc b/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service-lazy.rc
index e8549ed..63ded90 100644
--- a/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service-lazy.rc
+++ b/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service-lazy.rc
@@ -7,4 +7,4 @@
     group audio camera input drmrpc
     ioprio rt 4
     capabilities SYS_NICE
-    writepid /dev/cpuset/camera-daemon/tasks /dev/stune/top-app/tasks
+    task_profiles CameraServiceCapacity MaxPerformance
diff --git a/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service-lazy_64.rc b/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service-lazy_64.rc
index 2dfac76..953d1af 100644
--- a/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service-lazy_64.rc
+++ b/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service-lazy_64.rc
@@ -7,4 +7,4 @@
     group audio camera input drmrpc
     ioprio rt 4
     capabilities SYS_NICE
-    writepid /dev/cpuset/camera-daemon/tasks /dev/stune/top-app/tasks
+    task_profiles CameraServiceCapacity MaxPerformance
diff --git a/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service.rc b/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service.rc
index 913561b..f7ac9f8 100644
--- a/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service.rc
+++ b/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service.rc
@@ -5,4 +5,4 @@
     group audio camera input drmrpc
     ioprio rt 4
     capabilities SYS_NICE
-    writepid /dev/cpuset/camera-daemon/tasks /dev/stune/top-app/tasks
+    task_profiles CameraServiceCapacity MaxPerformance
diff --git a/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service_64.rc b/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service_64.rc
index fd4826e..a32dd46 100644
--- a/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service_64.rc
+++ b/camera/provider/2.4/default/android.hardware.camera.provider@2.4-service_64.rc
@@ -5,4 +5,4 @@
     group audio camera input drmrpc
     ioprio rt 4
     capabilities SYS_NICE
-    writepid /dev/cpuset/camera-daemon/tasks /dev/stune/top-app/tasks
+    task_profiles CameraServiceCapacity MaxPerformance
diff --git a/camera/provider/2.5/default/android.hardware.camera.provider@2.5-external-service.rc b/camera/provider/2.5/default/android.hardware.camera.provider@2.5-external-service.rc
index 107097e..b3b06b2 100644
--- a/camera/provider/2.5/default/android.hardware.camera.provider@2.5-external-service.rc
+++ b/camera/provider/2.5/default/android.hardware.camera.provider@2.5-external-service.rc
@@ -6,4 +6,4 @@
     group audio camera input drmrpc usb
     ioprio rt 4
     capabilities SYS_NICE
-    writepid /dev/cpuset/camera-daemon/tasks /dev/stune/top-app/tasks
+    task_profiles CameraServiceCapacity MaxPerformance
diff --git a/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service-lazy.rc b/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service-lazy.rc
index b45158a..7c5e69b 100644
--- a/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service-lazy.rc
+++ b/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service-lazy.rc
@@ -8,4 +8,4 @@
     group audio camera input drmrpc
     ioprio rt 4
     capabilities SYS_NICE
-    writepid /dev/cpuset/camera-daemon/tasks /dev/stune/top-app/tasks
+    task_profiles CameraServiceCapacity MaxPerformance
diff --git a/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service-lazy_64.rc b/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service-lazy_64.rc
index 955b28e..49bca8f 100644
--- a/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service-lazy_64.rc
+++ b/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service-lazy_64.rc
@@ -8,4 +8,4 @@
     group audio camera input drmrpc
     ioprio rt 4
     capabilities SYS_NICE
-    writepid /dev/cpuset/camera-daemon/tasks /dev/stune/top-app/tasks
+    task_profiles CameraServiceCapacity MaxPerformance
diff --git a/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service.rc b/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service.rc
index c065815..4bd1fb4 100644
--- a/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service.rc
+++ b/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service.rc
@@ -6,4 +6,4 @@
     group audio camera input drmrpc
     ioprio rt 4
     capabilities SYS_NICE
-    writepid /dev/cpuset/camera-daemon/tasks /dev/stune/top-app/tasks
+    task_profiles CameraServiceCapacity MaxPerformance
diff --git a/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service_64.rc b/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service_64.rc
index 63dd11d..b444325 100644
--- a/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service_64.rc
+++ b/camera/provider/2.5/default/android.hardware.camera.provider@2.5-service_64.rc
@@ -6,4 +6,4 @@
     group audio camera input drmrpc
     ioprio rt 4
     capabilities SYS_NICE
-    writepid /dev/cpuset/camera-daemon/tasks /dev/stune/top-app/tasks
+    task_profiles CameraServiceCapacity MaxPerformance
diff --git a/gnss/1.1/vts/functional/Android.bp b/gnss/1.1/vts/functional/Android.bp
index cc34290..237ac42 100644
--- a/gnss/1.1/vts/functional/Android.bp
+++ b/gnss/1.1/vts/functional/Android.bp
@@ -25,6 +25,7 @@
     static_libs: [
         "android.hardware.gnss@1.0",
         "android.hardware.gnss@1.1",
+        "android.hardware.gnss@2.0",
         "android.hardware.gnss@common-vts-lib",
     ],
     shared_libs: [
diff --git a/gnss/1.1/vts/functional/gnss_hal_test_cases.cpp b/gnss/1.1/vts/functional/gnss_hal_test_cases.cpp
index 503e419..7a7b6af 100644
--- a/gnss/1.1/vts/functional/gnss_hal_test_cases.cpp
+++ b/gnss/1.1/vts/functional/gnss_hal_test_cases.cpp
@@ -427,6 +427,7 @@
     sources.resize(1);
     sources[0] = source_to_blacklist;
 
+    // setBlacklist when location is on.
     auto result = gnss_configuration_hal->setBlacklist(sources);
     ASSERT_TRUE(result.isOk());
     EXPECT_TRUE(result);
diff --git a/gnss/2.0/vts/functional/gnss_hal_test.cpp b/gnss/2.0/vts/functional/gnss_hal_test.cpp
index 14ae43c..c01e91d 100644
--- a/gnss/2.0/vts/functional/gnss_hal_test.cpp
+++ b/gnss/2.0/vts/functional/gnss_hal_test.cpp
@@ -221,3 +221,46 @@
     capabilities_cbq_.store(capabilities);
     return Void();
 }
+
+GnssConstellationType_1_0 GnssHalTest::startLocationAndGetNonGpsConstellation() {
+    const int kLocationsToAwait = 3;
+
+    gnss_cb_->location_cbq_.reset();
+    StartAndCheckLocations(kLocationsToAwait);
+    const int location_called_count = gnss_cb_->location_cbq_.calledCount();
+
+    // Tolerate 1 less sv status to handle edge cases in reporting.
+    int sv_info_list_cbq_size = gnss_cb_->sv_info_list_cbq_.size();
+    EXPECT_GE(sv_info_list_cbq_size + 1, kLocationsToAwait);
+    ALOGD("Observed %d GnssSvStatus, while awaiting %d Locations (%d received)",
+          sv_info_list_cbq_size, kLocationsToAwait, location_called_count);
+
+    // Find first non-GPS constellation to blacklist. Exclude IRNSS in GnssConstellationType_2_0
+    // as blacklisting of this constellation is not supported in gnss@2.0.
+    const int kGnssSvStatusTimeout = 2;
+    GnssConstellationType_1_0 constellation_to_blacklist = GnssConstellationType_1_0::UNKNOWN;
+    for (int i = 0; i < sv_info_list_cbq_size; ++i) {
+        hidl_vec<IGnssCallback_2_0::GnssSvInfo> sv_info_list;
+        gnss_cb_->sv_info_list_cbq_.retrieve(sv_info_list, kGnssSvStatusTimeout);
+        for (IGnssCallback_2_0::GnssSvInfo sv_info : sv_info_list) {
+            if ((sv_info.v1_0.svFlag & IGnssCallback_2_0::GnssSvFlags::USED_IN_FIX) &&
+                (sv_info.constellation != GnssConstellationType_2_0::UNKNOWN) &&
+                (sv_info.constellation != GnssConstellationType_2_0::IRNSS) &&
+                (sv_info.constellation != GnssConstellationType_2_0::GPS)) {
+                // found a non-GPS V1_0 constellation
+                constellation_to_blacklist = Utils::mapConstellationType(sv_info.constellation);
+                break;
+            }
+        }
+        if (constellation_to_blacklist != GnssConstellationType_1_0::UNKNOWN) {
+            break;
+        }
+    }
+
+    if (constellation_to_blacklist == GnssConstellationType_1_0::UNKNOWN) {
+        ALOGI("No non-GPS constellations found, constellation blacklist test less effective.");
+        // Proceed functionally to blacklist something.
+        constellation_to_blacklist = GnssConstellationType_1_0::GLONASS;
+    }
+    return constellation_to_blacklist;
+}
diff --git a/gnss/2.0/vts/functional/gnss_hal_test.h b/gnss/2.0/vts/functional/gnss_hal_test.h
index 90a7866..5bfcb1f 100644
--- a/gnss/2.0/vts/functional/gnss_hal_test.h
+++ b/gnss/2.0/vts/functional/gnss_hal_test.h
@@ -34,6 +34,9 @@
 using android::hardware::gnss::V1_0::GnssLocationFlags;
 using android::hardware::gnss::V2_0::IGnss;
 
+using GnssConstellationType_1_0 = android::hardware::gnss::V1_0::GnssConstellationType;
+using GnssConstellationType_2_0 = android::hardware::gnss::V2_0::GnssConstellationType;
+
 using GnssLocation_1_0 = android::hardware::gnss::V1_0::GnssLocation;
 using GnssLocation_2_0 = android::hardware::gnss::V2_0::GnssLocation;
 
@@ -248,6 +251,16 @@
      */
     void SetPositionMode(const int min_interval_msec, const bool low_power_mode);
 
+    /*
+     * startLocationAndGetNonGpsConstellation:
+     * 1. Start location
+     * 2. Find and return first non-GPS constellation
+     *
+     * Note that location is not stopped in this method. The client should call
+     * StopAndClearLocations() after the call.
+     */
+    GnssConstellationType_1_0 startLocationAndGetNonGpsConstellation();
+
     sp<IGnss> gnss_hal_;         // GNSS HAL to call into
     sp<GnssCallback> gnss_cb_;   // Primary callback interface
 };
diff --git a/gnss/2.0/vts/functional/gnss_hal_test_cases.cpp b/gnss/2.0/vts/functional/gnss_hal_test_cases.cpp
index 39736cc..b42f432 100644
--- a/gnss/2.0/vts/functional/gnss_hal_test_cases.cpp
+++ b/gnss/2.0/vts/functional/gnss_hal_test_cases.cpp
@@ -23,8 +23,6 @@
 using android::hardware::hidl_string;
 using android::hardware::hidl_vec;
 
-using GnssConstellationType_2_0 = android::hardware::gnss::V2_0::GnssConstellationType;
-using GnssConstellationType_1_0 = android::hardware::gnss::V1_0::GnssConstellationType;
 using IGnssConfiguration_2_0 = android::hardware::gnss::V2_0::IGnssConfiguration;
 using IGnssConfiguration_1_1 = android::hardware::gnss::V1_1::IGnssConfiguration;
 using IAGnssRil_2_0 = android::hardware::gnss::V2_0::IAGnssRil;
@@ -480,31 +478,6 @@
 }
 
 /*
- * MapConstellationType:
- * Given a GnssConstellationType_2_0 type constellation, maps to its equivalent
- * GnssConstellationType_1_0 type constellation. For constellations that do not have
- * an equivalent value, maps to GnssConstellationType_1_0::UNKNOWN
- */
-GnssConstellationType_1_0 MapConstellationType(GnssConstellationType_2_0 constellation) {
-    switch (constellation) {
-        case GnssConstellationType_2_0::GPS:
-            return GnssConstellationType_1_0::GPS;
-        case GnssConstellationType_2_0::SBAS:
-            return GnssConstellationType_1_0::SBAS;
-        case GnssConstellationType_2_0::GLONASS:
-            return GnssConstellationType_1_0::GLONASS;
-        case GnssConstellationType_2_0::QZSS:
-            return GnssConstellationType_1_0::QZSS;
-        case GnssConstellationType_2_0::BEIDOU:
-            return GnssConstellationType_1_0::BEIDOU;
-        case GnssConstellationType_2_0::GALILEO:
-            return GnssConstellationType_1_0::GALILEO;
-        default:
-            return GnssConstellationType_1_0::UNKNOWN;
-    }
-}
-
-/*
  * FindStrongFrequentNonGpsSource:
  *
  * Search through a GnssSvStatus list for the strongest non-GPS satellite observed enough times
@@ -543,7 +516,7 @@
                 (sv_info.constellation != GnssConstellationType_2_0::GPS)) {
                 ComparableBlacklistedSource source;
                 source.id.svid = sv_info.v1_0.svid;
-                source.id.constellation = MapConstellationType(sv_info.constellation);
+                source.id.constellation = Utils::mapConstellationType(sv_info.constellation);
 
                 const auto& itSignal = mapSignals.find(source);
                 if (itSignal == mapSignals.end()) {
@@ -677,7 +650,7 @@
         hidl_vec<IGnssCallback_2_0::GnssSvInfo> sv_info_list;
         gnss_cb_->sv_info_list_cbq_.retrieve(sv_info_list, kGnssSvStatusTimeout);
         for (IGnssCallback_2_0::GnssSvInfo sv_info : sv_info_list) {
-            auto constellation = MapConstellationType(sv_info.constellation);
+            auto constellation = Utils::mapConstellationType(sv_info.constellation);
             EXPECT_FALSE((sv_info.v1_0.svid == source_to_blacklist.svid) &&
                          (constellation == source_to_blacklist.constellation) &&
                          (sv_info.v1_0.svFlag & IGnssCallback::GnssSvFlags::USED_IN_FIX));
@@ -719,7 +692,7 @@
             hidl_vec<IGnssCallback_2_0::GnssSvInfo> sv_info_list;
             gnss_cb_->sv_info_list_cbq_.retrieve(sv_info_list, kGnssSvStatusTimeout);
             for (IGnssCallback_2_0::GnssSvInfo sv_info : sv_info_list) {
-                auto constellation = MapConstellationType(sv_info.constellation);
+                auto constellation = Utils::mapConstellationType(sv_info.constellation);
                 if ((sv_info.v1_0.svid == source_to_blacklist.svid) &&
                     (constellation == source_to_blacklist.constellation) &&
                     (sv_info.v1_0.svFlag & IGnssCallback::GnssSvFlags::USED_IN_FIX)) {
@@ -735,7 +708,7 @@
 }
 
 /*
- * BlacklistConstellation:
+ * BlacklistConstellationWithLocationOff:
  *
  * 1) Turns on location, waits for 3 locations, ensuring they are valid, and checks corresponding
  * GnssStatus for any non-GPS constellations.
@@ -744,7 +717,7 @@
  * GnssStatus does not use any constellation but GPS.
  * 4a & b) Clean up by turning off location, and send in empty blacklist.
  */
-TEST_F(GnssHalTest, BlacklistConstellation) {
+TEST_F(GnssHalTest, BlacklistConstellationWithLocationOff) {
     if (!(gnss_cb_->last_capabilities_ & IGnssCallback::Capabilities::SATELLITE_BLACKLIST)) {
         ALOGI("Test BlacklistConstellation skipped. SATELLITE_BLACKLIST capability not supported.");
         return;
@@ -752,43 +725,12 @@
 
     const int kLocationsToAwait = 3;
 
-    gnss_cb_->location_cbq_.reset();
-    StartAndCheckLocations(kLocationsToAwait);
-    const int location_called_count = gnss_cb_->location_cbq_.calledCount();
+    // Find first non-GPS constellation to blacklist
+    GnssConstellationType_1_0 constellation_to_blacklist = startLocationAndGetNonGpsConstellation();
 
-    // Tolerate 1 less sv status to handle edge cases in reporting.
-    int sv_info_list_cbq_size = gnss_cb_->sv_info_list_cbq_.size();
-    EXPECT_GE(sv_info_list_cbq_size + 1, kLocationsToAwait);
-    ALOGD("Observed %d GnssSvStatus, while awaiting %d Locations (%d received)",
-          sv_info_list_cbq_size, kLocationsToAwait, location_called_count);
+    // Turns off location
+    StopAndClearLocations();
 
-    // Find first non-GPS constellation to blacklist. Exclude IRNSS in GnssConstellationType_2_0
-    // as blacklisting of this constellation is not supported in gnss@2.0.
-    const int kGnssSvStatusTimeout = 2;
-    GnssConstellationType_1_0 constellation_to_blacklist = GnssConstellationType_1_0::UNKNOWN;
-    for (int i = 0; i < sv_info_list_cbq_size; ++i) {
-        hidl_vec<IGnssCallback_2_0::GnssSvInfo> sv_info_list;
-        gnss_cb_->sv_info_list_cbq_.retrieve(sv_info_list, kGnssSvStatusTimeout);
-        for (IGnssCallback_2_0::GnssSvInfo sv_info : sv_info_list) {
-            if ((sv_info.v1_0.svFlag & IGnssCallback::GnssSvFlags::USED_IN_FIX) &&
-                (sv_info.constellation != GnssConstellationType_2_0::UNKNOWN) &&
-                (sv_info.constellation != GnssConstellationType_2_0::IRNSS) &&
-                (sv_info.constellation != GnssConstellationType_2_0::GPS)) {
-                // found a non-GPS V1_0 constellation
-                constellation_to_blacklist = MapConstellationType(sv_info.constellation);
-                break;
-            }
-        }
-        if (constellation_to_blacklist != GnssConstellationType_1_0::UNKNOWN) {
-            break;
-        }
-    }
-
-    if (constellation_to_blacklist == GnssConstellationType_1_0::UNKNOWN) {
-        ALOGI("No non-GPS constellations found, constellation blacklist test less effective.");
-        // Proceed functionally to blacklist something.
-        constellation_to_blacklist = GnssConstellationType_1_0::GLONASS;
-    }
     IGnssConfiguration_1_1::BlacklistedSource source_to_blacklist;
     source_to_blacklist.constellation = constellation_to_blacklist;
     source_to_blacklist.svid = 0;  // documented wildcard for all satellites in this constellation
@@ -802,6 +744,7 @@
     sources.resize(1);
     sources[0] = source_to_blacklist;
 
+    // setBlacklist when location is off.
     auto result = gnss_configuration_hal->setBlacklist(sources);
     ASSERT_TRUE(result.isOk());
     EXPECT_TRUE(result);
@@ -813,15 +756,88 @@
     StartAndCheckLocations(kLocationsToAwait);
 
     // Tolerate 1 less sv status to handle edge cases in reporting.
-    sv_info_list_cbq_size = gnss_cb_->sv_info_list_cbq_.size();
+    int sv_info_list_cbq_size = gnss_cb_->sv_info_list_cbq_.size();
     EXPECT_GE(sv_info_list_cbq_size + 1, kLocationsToAwait);
     ALOGD("Observed %d GnssSvStatus, while awaiting %d Locations", sv_info_list_cbq_size,
           kLocationsToAwait);
+    const int kGnssSvStatusTimeout = 2;
     for (int i = 0; i < sv_info_list_cbq_size; ++i) {
         hidl_vec<IGnssCallback_2_0::GnssSvInfo> sv_info_list;
         gnss_cb_->sv_info_list_cbq_.retrieve(sv_info_list, kGnssSvStatusTimeout);
         for (IGnssCallback_2_0::GnssSvInfo sv_info : sv_info_list) {
-            auto constellation = MapConstellationType(sv_info.constellation);
+            auto constellation = Utils::mapConstellationType(sv_info.constellation);
+            EXPECT_FALSE((constellation == source_to_blacklist.constellation) &&
+                         (sv_info.v1_0.svFlag & IGnssCallback::GnssSvFlags::USED_IN_FIX));
+        }
+    }
+
+    // clean up
+    StopAndClearLocations();
+    sources.resize(0);
+    result = gnss_configuration_hal->setBlacklist(sources);
+    ASSERT_TRUE(result.isOk());
+    EXPECT_TRUE(result);
+}
+
+/*
+ * BlacklistConstellationWithLocationOn:
+ *
+ * 1) Turns on location, waits for 3 locations, ensuring they are valid, and checks corresponding
+ * GnssStatus for any non-GPS constellations.
+ * 2a & b) Blacklist first non-GPS constellations, and turns off location.
+ * 3) Restart location, wait for 3 locations, ensuring they are valid, and checks corresponding
+ * GnssStatus does not use any constellation but GPS.
+ * 4a & b) Clean up by turning off location, and send in empty blacklist.
+ */
+TEST_F(GnssHalTest, BlacklistConstellationWithLocationOn) {
+    if (!(gnss_cb_->last_capabilities_ & IGnssCallback::Capabilities::SATELLITE_BLACKLIST)) {
+        ALOGI("Test BlacklistConstellation skipped. SATELLITE_BLACKLIST capability not supported.");
+        return;
+    }
+
+    const int kLocationsToAwait = 3;
+
+    // Find first non-GPS constellation to blacklist
+    GnssConstellationType_1_0 constellation_to_blacklist = startLocationAndGetNonGpsConstellation();
+
+    IGnssConfiguration_1_1::BlacklistedSource source_to_blacklist;
+    source_to_blacklist.constellation = constellation_to_blacklist;
+    source_to_blacklist.svid = 0;  // documented wildcard for all satellites in this constellation
+
+    auto gnss_configuration_hal_return = gnss_hal_->getExtensionGnssConfiguration_1_1();
+    ASSERT_TRUE(gnss_configuration_hal_return.isOk());
+    sp<IGnssConfiguration_1_1> gnss_configuration_hal = gnss_configuration_hal_return;
+    ASSERT_NE(gnss_configuration_hal, nullptr);
+
+    hidl_vec<IGnssConfiguration_1_1::BlacklistedSource> sources;
+    sources.resize(1);
+    sources[0] = source_to_blacklist;
+
+    // setBlacklist when location is on.
+    auto result = gnss_configuration_hal->setBlacklist(sources);
+    ASSERT_TRUE(result.isOk());
+    EXPECT_TRUE(result);
+
+    // Turns off location
+    StopAndClearLocations();
+
+    // retry and ensure constellation not used
+    gnss_cb_->sv_info_list_cbq_.reset();
+
+    gnss_cb_->location_cbq_.reset();
+    StartAndCheckLocations(kLocationsToAwait);
+
+    // Tolerate 1 less sv status to handle edge cases in reporting.
+    int sv_info_list_cbq_size = gnss_cb_->sv_info_list_cbq_.size();
+    EXPECT_GE(sv_info_list_cbq_size + 1, kLocationsToAwait);
+    ALOGD("Observed %d GnssSvStatus, while awaiting %d Locations", sv_info_list_cbq_size,
+          kLocationsToAwait);
+    const int kGnssSvStatusTimeout = 2;
+    for (int i = 0; i < sv_info_list_cbq_size; ++i) {
+        hidl_vec<IGnssCallback_2_0::GnssSvInfo> sv_info_list;
+        gnss_cb_->sv_info_list_cbq_.retrieve(sv_info_list, kGnssSvStatusTimeout);
+        for (IGnssCallback_2_0::GnssSvInfo sv_info : sv_info_list) {
+            auto constellation = Utils::mapConstellationType(sv_info.constellation);
             EXPECT_FALSE((constellation == source_to_blacklist.constellation) &&
                          (sv_info.v1_0.svFlag & IGnssCallback::GnssSvFlags::USED_IN_FIX));
         }
diff --git a/gnss/common/utils/vts/Android.bp b/gnss/common/utils/vts/Android.bp
index 1988171..ed383fc 100644
--- a/gnss/common/utils/vts/Android.bp
+++ b/gnss/common/utils/vts/Android.bp
@@ -29,6 +29,7 @@
     export_include_dirs: ["include"],
     shared_libs: [
         "android.hardware.gnss@1.0",
+        "android.hardware.gnss@2.0",
         "android.hardware.gnss.measurement_corrections@1.0",
     ],
     static_libs: [
diff --git a/gnss/common/utils/vts/Utils.cpp b/gnss/common/utils/vts/Utils.cpp
index 51d3ea1..4e42f75 100644
--- a/gnss/common/utils/vts/Utils.cpp
+++ b/gnss/common/utils/vts/Utils.cpp
@@ -139,6 +139,31 @@
     return mockCorrections;
 }
 
+/*
+ * MapConstellationType:
+ * Given a GnssConstellationType_2_0 type constellation, maps to its equivalent
+ * GnssConstellationType_1_0 type constellation. For constellations that do not have
+ * an equivalent value, maps to GnssConstellationType_1_0::UNKNOWN
+ */
+GnssConstellationType_1_0 Utils::mapConstellationType(GnssConstellationType_2_0 constellation) {
+    switch (constellation) {
+        case GnssConstellationType_2_0::GPS:
+            return GnssConstellationType_1_0::GPS;
+        case GnssConstellationType_2_0::SBAS:
+            return GnssConstellationType_1_0::SBAS;
+        case GnssConstellationType_2_0::GLONASS:
+            return GnssConstellationType_1_0::GLONASS;
+        case GnssConstellationType_2_0::QZSS:
+            return GnssConstellationType_1_0::QZSS;
+        case GnssConstellationType_2_0::BEIDOU:
+            return GnssConstellationType_1_0::BEIDOU;
+        case GnssConstellationType_2_0::GALILEO:
+            return GnssConstellationType_1_0::GALILEO;
+        default:
+            return GnssConstellationType_1_0::UNKNOWN;
+    }
+}
+
 }  // namespace common
 }  // namespace gnss
 }  // namespace hardware
diff --git a/gnss/common/utils/vts/include/Utils.h b/gnss/common/utils/vts/include/Utils.h
index dce4c7b..b5f833b 100644
--- a/gnss/common/utils/vts/include/Utils.h
+++ b/gnss/common/utils/vts/include/Utils.h
@@ -18,8 +18,11 @@
 #define android_hardware_gnss_common_vts_Utils_H_
 
 #include <android/hardware/gnss/1.0/IGnss.h>
+#include <android/hardware/gnss/2.0/IGnss.h>
 #include <android/hardware/gnss/measurement_corrections/1.0/IMeasurementCorrections.h>
 
+using GnssConstellationType_1_0 = android::hardware::gnss::V1_0::GnssConstellationType;
+using GnssConstellationType_2_0 = android::hardware::gnss::V2_0::GnssConstellationType;
 using GnssLocation = ::android::hardware::gnss::V1_0::GnssLocation;
 using namespace android::hardware::gnss::measurement_corrections::V1_0;
 
@@ -32,6 +35,8 @@
     static void checkLocation(const GnssLocation& location, bool check_speed,
                               bool check_more_accuracies);
     static const MeasurementCorrections getMockMeasurementCorrections();
+
+    static GnssConstellationType_1_0 mapConstellationType(GnssConstellationType_2_0 constellation);
 };
 
 }  // namespace common
diff --git a/identity/aidl/aidl_api/android.hardware.identity/2/.hash b/identity/aidl/aidl_api/android.hardware.identity/2/.hash
index 1b2c1b6..036ce84 100644
--- a/identity/aidl/aidl_api/android.hardware.identity/2/.hash
+++ b/identity/aidl/aidl_api/android.hardware.identity/2/.hash
@@ -1 +1 @@
-3b0b10b618dbc4bf283aa2bf78833ad3de0a5928
+194e04be642728623d65ec8321a3764fdea52ae0
diff --git a/identity/aidl/aidl_api/android.hardware.identity/2/android/hardware/identity/IIdentityCredential.aidl b/identity/aidl/aidl_api/android.hardware.identity/2/android/hardware/identity/IIdentityCredential.aidl
index e8e93f8..88104d9 100644
--- a/identity/aidl/aidl_api/android.hardware.identity/2/android/hardware/identity/IIdentityCredential.aidl
+++ b/identity/aidl/aidl_api/android.hardware.identity/2/android/hardware/identity/IIdentityCredential.aidl
@@ -28,4 +28,5 @@
   void finishRetrieval(out byte[] mac, out byte[] deviceNameSpaces);
   android.hardware.identity.Certificate generateSigningKeyPair(out byte[] signingKeyBlob);
   void setRequestedNamespaces(in android.hardware.identity.RequestNamespace[] requestNamespaces);
+  void setVerificationToken(in android.hardware.keymaster.VerificationToken verificationToken);
 }
diff --git a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IIdentityCredential.aidl b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IIdentityCredential.aidl
index e8e93f8..88104d9 100644
--- a/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IIdentityCredential.aidl
+++ b/identity/aidl/aidl_api/android.hardware.identity/current/android/hardware/identity/IIdentityCredential.aidl
@@ -28,4 +28,5 @@
   void finishRetrieval(out byte[] mac, out byte[] deviceNameSpaces);
   android.hardware.identity.Certificate generateSigningKeyPair(out byte[] signingKeyBlob);
   void setRequestedNamespaces(in android.hardware.identity.RequestNamespace[] requestNamespaces);
+  void setVerificationToken(in android.hardware.keymaster.VerificationToken verificationToken);
 }
diff --git a/identity/aidl/android/hardware/identity/IIdentityCredential.aidl b/identity/aidl/android/hardware/identity/IIdentityCredential.aidl
index 7cd25e6..d7f47e8 100644
--- a/identity/aidl/android/hardware/identity/IIdentityCredential.aidl
+++ b/identity/aidl/android/hardware/identity/IIdentityCredential.aidl
@@ -20,6 +20,7 @@
 import android.hardware.identity.RequestNamespace;
 import android.hardware.identity.SecureAccessControlProfile;
 import android.hardware.keymaster.HardwareAuthToken;
+import android.hardware.keymaster.VerificationToken;
 
 @VintfStability
 interface IIdentityCredential {
@@ -71,10 +72,11 @@
 
     /**
      * Creates a challenge value to be used for proving successful user authentication. This
-     * is included in the authToken passed to the startRetrieval() method.
+     * is included in the authToken passed to the startRetrieval() method and the
+     * verificationToken passed to the setVerificationToken() method.
      *
      * This method may only be called once per instance. If called more than once, STATUS_FAILED
-     * will be returned.
+     * will be returned. If user authentication is not needed, this method may not be called.
      *
      * @return challenge, a non-zero number.
      */
@@ -83,7 +85,8 @@
     /**
      * Start an entry retrieval process.
      *
-     * The setRequestedNamespaces() method will be called before this method.
+     * The setRequestedNamespaces() and setVerificationToken() methods will be called before
+     * this method is called.
      *
      * This method be called after createEphemeralKeyPair(), setReaderEphemeralPublicKey(),
      * createAuthChallenge() and before startRetrieveEntry(). This method call is followed by
@@ -96,7 +99,19 @@
      * must be identical for each startRetrieval() invocation. If this is not the case, this call
      * fails with the STATUS_SESSION_TRANSCRIPT_MISMATCH error.
      *
-     * If the provided authToken is not valid this method fails with STATUS_INVALID_AUTH_TOKEN.
+     * If either authToken or verificationToken (as passed with setVerificationToken())
+     * is not valid this method fails with STATUS_INVALID_AUTH_TOKEN. Note that valid tokens
+     * are only passed if they are actually needed and available (this can be detected by
+     * the timestamp being set to zero). For example, if no data items with access control
+     * profiles using user authentication are requested, the tokens are not filled in.
+     * It's also possible that no usable auth token is actually available (it could be the user
+     * never unlocked the device within the timeouts in the access control profiles) and
+     * in this case the tokens aren't filled in either.
+     *
+     * For test credentials (identified by the testCredential boolean in the CredentialData
+     * CBOR created at provisioning time), the |mac| field in both the authToken and
+     * verificationToken should not be checked against the shared HMAC key (see IKeyMasterDevice
+     * for details). This is to enable VTS tests to check for correct behavior.
      *
      * Each of the provided accessControlProfiles is checked in this call. If they are not
      * all valid, the call fails with STATUS_INVALID_DATA.
@@ -179,7 +194,8 @@
      *
      * @param authToken
      *   The authentication token that proves the user was authenticated, as required
-     *   by one or more of the provided accessControlProfiles. See above.
+     *   by one or more of the provided accessControlProfiles. This token is only valid
+     *   if the timestamp field is non-zero. See above.
      *
      * @param itemsRequest
      *   If non-empty, contains request data that is signed by the reader. See above.
@@ -358,4 +374,13 @@
      * @param requestNamespaces Namespaces and data items which will be requested.
      */
     void setRequestedNamespaces(in RequestNamespace[] requestNamespaces);
+
+   /**
+    * Sets the VerificationToken. This method must be called before startRetrieval() is
+    * called. This token uses the same challenge as returned by createAuthChallenge().
+    *
+    * @param verificationToken
+    *   The verification token. This token is only valid if the timestamp field is non-zero.
+    */
+    void setVerificationToken(in VerificationToken verificationToken);
 }
diff --git a/identity/aidl/default/IdentityCredential.cpp b/identity/aidl/default/IdentityCredential.cpp
index ff4107a..381eb84 100644
--- a/identity/aidl/default/IdentityCredential.cpp
+++ b/identity/aidl/default/IdentityCredential.cpp
@@ -198,15 +198,8 @@
     return false;
 }
 
-Timestamp clockGetTime() {
-    struct timespec time;
-    clock_gettime(CLOCK_MONOTONIC, &time);
-    Timestamp ts;
-    ts.milliSeconds = time.tv_sec * 1000 + time.tv_nsec / 1000000;
-    return ts;
-}
-
 bool checkUserAuthentication(const SecureAccessControlProfile& profile,
+                             const VerificationToken& verificationToken,
                              const HardwareAuthToken& authToken, uint64_t authChallenge) {
     if (profile.secureUserId != authToken.userId) {
         LOG(ERROR) << "secureUserId in profile (" << profile.secureUserId
@@ -214,6 +207,15 @@
         return false;
     }
 
+    if (verificationToken.timestamp.milliSeconds == 0) {
+        LOG(ERROR) << "VerificationToken is not set";
+        return false;
+    }
+    if (authToken.timestamp.milliSeconds == 0) {
+        LOG(ERROR) << "AuthToken is not set";
+        return false;
+    }
+
     if (profile.timeoutMillis == 0) {
         if (authToken.challenge == 0) {
             LOG(ERROR) << "No challenge in authToken";
@@ -227,19 +229,11 @@
         return true;
     }
 
-    // Note that the Epoch for timestamps in HardwareAuthToken is at the
-    // discretion of the vendor:
+    // Timeout-based user auth follows. The verification token conveys what the
+    // time is right now in the environment which generated the auth token. This
+    // is what makes it possible to do timeout-based checks.
     //
-    //   "[...] since some starting point (generally the most recent device
-    //    boot) which all of the applications within one secure environment
-    //    must agree upon."
-    //
-    // Therefore, if this software implementation is used on a device which isn't
-    // the emulator then the assumption that the epoch is the same as used in
-    // clockGetTime above will not hold. This is OK as this software
-    // implementation should never be used on a real device.
-    //
-    Timestamp now = clockGetTime();
+    const Timestamp now = verificationToken.timestamp;
     if (authToken.timestamp.milliSeconds > now.milliSeconds) {
         LOG(ERROR) << "Timestamp in authToken (" << authToken.timestamp.milliSeconds
                    << ") is in the future (now: " << now.milliSeconds << ")";
@@ -261,6 +255,12 @@
     return ndk::ScopedAStatus::ok();
 }
 
+ndk::ScopedAStatus IdentityCredential::setVerificationToken(
+        const VerificationToken& verificationToken) {
+    verificationToken_ = verificationToken;
+    return ndk::ScopedAStatus::ok();
+}
+
 ndk::ScopedAStatus IdentityCredential::startRetrieval(
         const vector<SecureAccessControlProfile>& accessControlProfiles,
         const HardwareAuthToken& authToken, const vector<uint8_t>& itemsRequest,
@@ -483,7 +483,8 @@
         }
         int accessControlCheck = IIdentityCredentialStore::STATUS_OK;
         if (profile.userAuthenticationRequired) {
-            if (!haveAuthToken || !checkUserAuthentication(profile, authToken, authChallenge_)) {
+            if (!haveAuthToken ||
+                !checkUserAuthentication(profile, verificationToken_, authToken, authChallenge_)) {
                 accessControlCheck = IIdentityCredentialStore::STATUS_USER_AUTHENTICATION_FAILED;
             }
         } else if (profile.readerCertificate.encodedCertificate.size() > 0) {
diff --git a/identity/aidl/default/IdentityCredential.h b/identity/aidl/default/IdentityCredential.h
index a8bad88..a82531d 100644
--- a/identity/aidl/default/IdentityCredential.h
+++ b/identity/aidl/default/IdentityCredential.h
@@ -19,6 +19,7 @@
 
 #include <aidl/android/hardware/identity/BnIdentityCredential.h>
 #include <aidl/android/hardware/keymaster/HardwareAuthToken.h>
+#include <aidl/android/hardware/keymaster/VerificationToken.h>
 #include <android/hardware/identity/support/IdentityCredentialSupport.h>
 
 #include <map>
@@ -31,6 +32,7 @@
 namespace aidl::android::hardware::identity {
 
 using ::aidl::android::hardware::keymaster::HardwareAuthToken;
+using ::aidl::android::hardware::keymaster::VerificationToken;
 using ::std::map;
 using ::std::set;
 using ::std::string;
@@ -55,6 +57,7 @@
     ndk::ScopedAStatus createAuthChallenge(int64_t* outChallenge) override;
     ndk::ScopedAStatus setRequestedNamespaces(
             const vector<RequestNamespace>& requestNamespaces) override;
+    ndk::ScopedAStatus setVerificationToken(const VerificationToken& verificationToken) override;
     ndk::ScopedAStatus startRetrieval(
             const vector<SecureAccessControlProfile>& accessControlProfiles,
             const HardwareAuthToken& authToken, const vector<uint8_t>& itemsRequest,
@@ -93,6 +96,9 @@
     // Set by setRequestedNamespaces()
     vector<RequestNamespace> requestNamespaces_;
 
+    // Set by setVerificationToken().
+    VerificationToken verificationToken_;
+
     // Set at startRetrieval() time.
     map<int32_t, int> profileIdToAccessCheckResult_;
     vector<uint8_t> signingKeyBlob_;
diff --git a/identity/aidl/default/service.cpp b/identity/aidl/default/service.cpp
index f05c615..bf95df5 100644
--- a/identity/aidl/default/service.cpp
+++ b/identity/aidl/default/service.cpp
@@ -22,9 +22,14 @@
 
 #include "IdentityCredentialStore.h"
 
+using ::android::base::InitLogging;
+using ::android::base::StderrLogger;
+
 using aidl::android::hardware::identity::IdentityCredentialStore;
 
-int main() {
+int main(int /*argc*/, char* argv[]) {
+    InitLogging(argv, StderrLogger);
+
     ABinderProcess_setThreadPoolMaxThreadCount(0);
     std::shared_ptr<IdentityCredentialStore> store =
             ndk::SharedRefBase::make<IdentityCredentialStore>();
diff --git a/identity/aidl/vts/VtsHalIdentityEndToEndTest.cpp b/identity/aidl/vts/VtsHalIdentityEndToEndTest.cpp
index 807feab..17145b4 100644
--- a/identity/aidl/vts/VtsHalIdentityEndToEndTest.cpp
+++ b/identity/aidl/vts/VtsHalIdentityEndToEndTest.cpp
@@ -43,6 +43,7 @@
 using ::android::binder::Status;
 
 using ::android::hardware::keymaster::HardwareAuthToken;
+using ::android::hardware::keymaster::VerificationToken;
 
 class IdentityAidl : public testing::TestWithParam<std::string> {
   public:
@@ -82,7 +83,20 @@
                                                           // Profile 1 (no authentication)
                                                           {1, {}, false, 0}};
 
+    // It doesn't matter since no user auth is needed in this particular test,
+    // but for good measure, clear out the tokens we pass to the HAL.
     HardwareAuthToken authToken;
+    VerificationToken verificationToken;
+    authToken.challenge = 0;
+    authToken.userId = 0;
+    authToken.authenticatorId = 0;
+    authToken.authenticatorType = ::android::hardware::keymaster::HardwareAuthenticatorType::NONE;
+    authToken.timestamp.milliSeconds = 0;
+    authToken.mac.clear();
+    verificationToken.challenge = 0;
+    verificationToken.timestamp.milliSeconds = 0;
+    verificationToken.securityLevel = ::android::hardware::keymaster::SecurityLevel::SOFTWARE;
+    verificationToken.mac.clear();
 
     // Here's the actual test data:
     const vector<test_utils::TestEntryData> testEntries = {
@@ -274,7 +288,10 @@
     ASSERT_TRUE(credential->generateSigningKeyPair(&signingKeyBlob, &signingKeyCertificate).isOk());
 
     vector<RequestNamespace> requestedNamespaces = test_utils::buildRequestNamespaces(testEntries);
-    ASSERT_TRUE(credential->setRequestedNamespaces(requestedNamespaces).isOk());
+    // OK to fail, not available in v1 HAL
+    credential->setRequestedNamespaces(requestedNamespaces).isOk();
+    // OK to fail, not available in v1 HAL
+    credential->setVerificationToken(verificationToken);
     ASSERT_TRUE(credential
                         ->startRetrieval(secureProfiles.value(), authToken, itemsRequestBytes,
                                          signingKeyBlob, sessionTranscriptBytes,
diff --git a/keymaster/4.0/support/include/keymasterV4_0/keymaster_utils.h b/keymaster/4.0/support/include/keymasterV4_0/keymaster_utils.h
index 61645f8..f585d62 100644
--- a/keymaster/4.0/support/include/keymasterV4_0/keymaster_utils.h
+++ b/keymaster/4.0/support/include/keymasterV4_0/keymaster_utils.h
@@ -18,6 +18,8 @@
 #define HARDWARE_INTERFACES_KEYMASTER_40_SUPPORT_KEYMASTER_UTILS_H_
 
 #include <android/hardware/keymaster/4.0/types.h>
+#include <optional>
+#include <vector>
 
 namespace android {
 namespace hardware {
@@ -52,6 +54,15 @@
 HardwareAuthToken hidlVec2AuthToken(const hidl_vec<uint8_t>& buffer);
 hidl_vec<uint8_t> authToken2HidlVec(const HardwareAuthToken& token);
 
+// Serializes and deserializes a verification token. This format is private and
+// not stable between releases and should not be persisted to disk.
+//
+// Currently doesn't support the |parametersVerified| field, will fail if set.
+//
+std::optional<VerificationToken> deserializeVerificationToken(
+        const std::vector<uint8_t>& serializedToken);
+std::optional<std::vector<uint8_t>> serializeVerificationToken(const VerificationToken& token);
+
 uint32_t getOsVersion();
 uint32_t getOsPatchlevel();
 
diff --git a/keymaster/4.0/support/keymaster_utils.cpp b/keymaster/4.0/support/keymaster_utils.cpp
index 850a776..366cd0e 100644
--- a/keymaster/4.0/support/keymaster_utils.cpp
+++ b/keymaster/4.0/support/keymaster_utils.cpp
@@ -16,6 +16,7 @@
 
 #include <regex.h>
 
+#include <android-base/logging.h>
 #include <android-base/properties.h>
 #include <hardware/hw_auth_token.h>
 #include <keymasterV4_0/keymaster_utils.h>
@@ -110,6 +111,80 @@
     return token;
 }
 
+void appendUint64(std::vector<uint8_t>& vec, uint64_t value) {
+    for (size_t n = 0; n < sizeof(uint64_t); n++) {
+        uint8_t byte = (value >> (n * 8)) & 0xff;
+        vec.push_back(byte);
+    }
+}
+
+uint64_t extractUint64(const std::vector<uint8_t>& data, size_t offset) {
+    uint64_t value = 0;
+    for (size_t n = 0; n < sizeof(uint64_t); n++) {
+        uint8_t byte = data[offset + n];
+        value |= byte << (n * 8);
+    }
+    return value;
+}
+
+void appendUint32(std::vector<uint8_t>& vec, uint32_t value) {
+    for (size_t n = 0; n < sizeof(uint32_t); n++) {
+        uint8_t byte = (value >> (n * 8)) & 0xff;
+        vec.push_back(byte);
+    }
+}
+
+uint32_t extractUint32(const std::vector<uint8_t>& data, size_t offset) {
+    uint32_t value = 0;
+    for (size_t n = 0; n < sizeof(uint32_t); n++) {
+        uint8_t byte = data[offset + n];
+        value |= byte << (n * 8);
+    }
+    return value;
+}
+
+std::optional<std::vector<uint8_t>> serializeVerificationToken(const VerificationToken& token) {
+    if (token.parametersVerified.size() > 0) {
+        LOG(ERROR) << "Serializing verification tokens with parametersVerified is not supported";
+        return {};
+    }
+    if (!(token.mac.size() == 0 || token.mac.size() == 32)) {
+        LOG(ERROR) << "Unexpected MAC size " << token.mac.size() << ", expected 0 or 32";
+        return {};
+    }
+    std::vector<uint8_t> serializedToken;
+    appendUint64(serializedToken, token.challenge);
+    appendUint64(serializedToken, token.timestamp);
+    appendUint32(serializedToken, uint32_t(token.securityLevel));
+    appendUint32(serializedToken, token.mac.size());
+    serializedToken.insert(serializedToken.end(), token.mac.begin(), token.mac.end());
+    return serializedToken;
+}
+
+std::optional<VerificationToken> deserializeVerificationToken(
+        const std::vector<uint8_t>& serializedToken) {
+    if (serializedToken.size() < 24) {
+        LOG(ERROR) << "Unexpected serialized VerificationToken size " << serializedToken.size()
+                   << ", expected at least 24 bytes";
+        return {};
+    }
+    VerificationToken token;
+    token.challenge = extractUint64(serializedToken, 0);
+    token.timestamp = extractUint64(serializedToken, 8);
+    token.securityLevel = SecurityLevel(extractUint32(serializedToken, 16));
+    size_t macSize = extractUint32(serializedToken, 20);
+    size_t expectedSerializedSize = 24 + macSize;
+    if (serializedToken.size() != expectedSerializedSize) {
+        LOG(ERROR) << "Unexpected serialized VerificationToken size " << serializedToken.size()
+                   << ", expected " << expectedSerializedSize;
+        return {};
+    }
+    if (macSize > 0) {
+        token.mac = std::vector<uint8_t>(serializedToken.begin() + 24, serializedToken.end());
+    }
+    return token;
+}
+
 namespace {
 
 constexpr char kPlatformVersionProp[] = "ro.build.version.release";
diff --git a/keymaster/aidl/Android.bp b/keymaster/aidl/Android.bp
index 8d51e97..5206721 100644
--- a/keymaster/aidl/Android.bp
+++ b/keymaster/aidl/Android.bp
@@ -15,7 +15,10 @@
             },
         },
     },
-    versions: ["1"],
+    versions: [
+        "1",
+        "2",
+    ],
 }
 
 // This is a reminder that the next version of keymaster should be frozen at
diff --git a/keymaster/aidl/aidl_api/android.hardware.keymaster/2/.hash b/keymaster/aidl/aidl_api/android.hardware.keymaster/2/.hash
new file mode 100644
index 0000000..9d5974e
--- /dev/null
+++ b/keymaster/aidl/aidl_api/android.hardware.keymaster/2/.hash
@@ -0,0 +1 @@
+91ab0be1887410935f564e3938ff12c5f5f8c59d
diff --git a/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/HardwareAuthToken.aidl b/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/HardwareAuthToken.aidl
new file mode 100644
index 0000000..db1df2b
--- /dev/null
+++ b/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/HardwareAuthToken.aidl
@@ -0,0 +1,27 @@
+///////////////////////////////////////////////////////////////////////////////
+// THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
+///////////////////////////////////////////////////////////////////////////////
+
+// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
+// edit this file. It looks like you are doing that because you have modified
+// an AIDL interface in a backward-incompatible way, e.g., deleting a function
+// from an interface or a field from a parcelable and it broke the build. That
+// breakage is intended.
+//
+// You must not make a backward incompatible changes to the AIDL files built
+// with the aidl_interface module type with versions property set. The module
+// type is used to build AIDL files in a way that they can be used across
+// independently updatable components of the system. If a device is shipped
+// with such a backward incompatible change, it has a high risk of breaking
+// later when a module using the interface is updated, e.g., Mainline modules.
+
+package android.hardware.keymaster;
+@VintfStability
+parcelable HardwareAuthToken {
+  long challenge;
+  long userId;
+  long authenticatorId;
+  android.hardware.keymaster.HardwareAuthenticatorType authenticatorType;
+  android.hardware.keymaster.Timestamp timestamp;
+  byte[] mac;
+}
diff --git a/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/HardwareAuthenticatorType.aidl b/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/HardwareAuthenticatorType.aidl
new file mode 100644
index 0000000..924567f
--- /dev/null
+++ b/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/HardwareAuthenticatorType.aidl
@@ -0,0 +1,25 @@
+///////////////////////////////////////////////////////////////////////////////
+// THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
+///////////////////////////////////////////////////////////////////////////////
+
+// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
+// edit this file. It looks like you are doing that because you have modified
+// an AIDL interface in a backward-incompatible way, e.g., deleting a function
+// from an interface or a field from a parcelable and it broke the build. That
+// breakage is intended.
+//
+// You must not make a backward incompatible changes to the AIDL files built
+// with the aidl_interface module type with versions property set. The module
+// type is used to build AIDL files in a way that they can be used across
+// independently updatable components of the system. If a device is shipped
+// with such a backward incompatible change, it has a high risk of breaking
+// later when a module using the interface is updated, e.g., Mainline modules.
+
+package android.hardware.keymaster;
+@Backing(type="int") @VintfStability
+enum HardwareAuthenticatorType {
+  NONE = 0,
+  PASSWORD = 1,
+  FINGERPRINT = 2,
+  ANY = -1,
+}
diff --git a/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/SecurityLevel.aidl b/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/SecurityLevel.aidl
new file mode 100644
index 0000000..127c1bf
--- /dev/null
+++ b/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/SecurityLevel.aidl
@@ -0,0 +1,24 @@
+///////////////////////////////////////////////////////////////////////////////
+// THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
+///////////////////////////////////////////////////////////////////////////////
+
+// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
+// edit this file. It looks like you are doing that because you have modified
+// an AIDL interface in a backward-incompatible way, e.g., deleting a function
+// from an interface or a field from a parcelable and it broke the build. That
+// breakage is intended.
+//
+// You must not make a backward incompatible changes to the AIDL files built
+// with the aidl_interface module type with versions property set. The module
+// type is used to build AIDL files in a way that they can be used across
+// independently updatable components of the system. If a device is shipped
+// with such a backward incompatible change, it has a high risk of breaking
+// later when a module using the interface is updated, e.g., Mainline modules.
+
+package android.hardware.keymaster;
+@Backing(type="int") @VintfStability
+enum SecurityLevel {
+  SOFTWARE = 0,
+  TRUSTED_ENVIRONMENT = 1,
+  STRONGBOX = 2,
+}
diff --git a/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/Timestamp.aidl b/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/Timestamp.aidl
new file mode 100644
index 0000000..45fa1ae
--- /dev/null
+++ b/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/Timestamp.aidl
@@ -0,0 +1,22 @@
+///////////////////////////////////////////////////////////////////////////////
+// THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
+///////////////////////////////////////////////////////////////////////////////
+
+// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
+// edit this file. It looks like you are doing that because you have modified
+// an AIDL interface in a backward-incompatible way, e.g., deleting a function
+// from an interface or a field from a parcelable and it broke the build. That
+// breakage is intended.
+//
+// You must not make a backward incompatible changes to the AIDL files built
+// with the aidl_interface module type with versions property set. The module
+// type is used to build AIDL files in a way that they can be used across
+// independently updatable components of the system. If a device is shipped
+// with such a backward incompatible change, it has a high risk of breaking
+// later when a module using the interface is updated, e.g., Mainline modules.
+
+package android.hardware.keymaster;
+@VintfStability
+parcelable Timestamp {
+  long milliSeconds;
+}
diff --git a/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/VerificationToken.aidl b/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/VerificationToken.aidl
new file mode 100644
index 0000000..0633765
--- /dev/null
+++ b/keymaster/aidl/aidl_api/android.hardware.keymaster/2/android/hardware/keymaster/VerificationToken.aidl
@@ -0,0 +1,25 @@
+///////////////////////////////////////////////////////////////////////////////
+// THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
+///////////////////////////////////////////////////////////////////////////////
+
+// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
+// edit this file. It looks like you are doing that because you have modified
+// an AIDL interface in a backward-incompatible way, e.g., deleting a function
+// from an interface or a field from a parcelable and it broke the build. That
+// breakage is intended.
+//
+// You must not make a backward incompatible changes to the AIDL files built
+// with the aidl_interface module type with versions property set. The module
+// type is used to build AIDL files in a way that they can be used across
+// independently updatable components of the system. If a device is shipped
+// with such a backward incompatible change, it has a high risk of breaking
+// later when a module using the interface is updated, e.g., Mainline modules.
+
+package android.hardware.keymaster;
+@VintfStability
+parcelable VerificationToken {
+  long challenge;
+  android.hardware.keymaster.Timestamp timestamp;
+  android.hardware.keymaster.SecurityLevel securityLevel;
+  byte[] mac;
+}
diff --git a/keymaster/aidl/aidl_api/android.hardware.keymaster/current/android/hardware/keymaster/SecurityLevel.aidl b/keymaster/aidl/aidl_api/android.hardware.keymaster/current/android/hardware/keymaster/SecurityLevel.aidl
new file mode 100644
index 0000000..127c1bf
--- /dev/null
+++ b/keymaster/aidl/aidl_api/android.hardware.keymaster/current/android/hardware/keymaster/SecurityLevel.aidl
@@ -0,0 +1,24 @@
+///////////////////////////////////////////////////////////////////////////////
+// THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
+///////////////////////////////////////////////////////////////////////////////
+
+// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
+// edit this file. It looks like you are doing that because you have modified
+// an AIDL interface in a backward-incompatible way, e.g., deleting a function
+// from an interface or a field from a parcelable and it broke the build. That
+// breakage is intended.
+//
+// You must not make a backward incompatible changes to the AIDL files built
+// with the aidl_interface module type with versions property set. The module
+// type is used to build AIDL files in a way that they can be used across
+// independently updatable components of the system. If a device is shipped
+// with such a backward incompatible change, it has a high risk of breaking
+// later when a module using the interface is updated, e.g., Mainline modules.
+
+package android.hardware.keymaster;
+@Backing(type="int") @VintfStability
+enum SecurityLevel {
+  SOFTWARE = 0,
+  TRUSTED_ENVIRONMENT = 1,
+  STRONGBOX = 2,
+}
diff --git a/keymaster/aidl/aidl_api/android.hardware.keymaster/current/android/hardware/keymaster/VerificationToken.aidl b/keymaster/aidl/aidl_api/android.hardware.keymaster/current/android/hardware/keymaster/VerificationToken.aidl
new file mode 100644
index 0000000..0633765
--- /dev/null
+++ b/keymaster/aidl/aidl_api/android.hardware.keymaster/current/android/hardware/keymaster/VerificationToken.aidl
@@ -0,0 +1,25 @@
+///////////////////////////////////////////////////////////////////////////////
+// THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
+///////////////////////////////////////////////////////////////////////////////
+
+// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
+// edit this file. It looks like you are doing that because you have modified
+// an AIDL interface in a backward-incompatible way, e.g., deleting a function
+// from an interface or a field from a parcelable and it broke the build. That
+// breakage is intended.
+//
+// You must not make a backward incompatible changes to the AIDL files built
+// with the aidl_interface module type with versions property set. The module
+// type is used to build AIDL files in a way that they can be used across
+// independently updatable components of the system. If a device is shipped
+// with such a backward incompatible change, it has a high risk of breaking
+// later when a module using the interface is updated, e.g., Mainline modules.
+
+package android.hardware.keymaster;
+@VintfStability
+parcelable VerificationToken {
+  long challenge;
+  android.hardware.keymaster.Timestamp timestamp;
+  android.hardware.keymaster.SecurityLevel securityLevel;
+  byte[] mac;
+}
diff --git a/keymaster/aidl/android/hardware/keymaster/SecurityLevel.aidl b/keymaster/aidl/android/hardware/keymaster/SecurityLevel.aidl
new file mode 100644
index 0000000..f129783
--- /dev/null
+++ b/keymaster/aidl/android/hardware/keymaster/SecurityLevel.aidl
@@ -0,0 +1,32 @@
+/*
+ * Copyright 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 android.hardware.keymaster;
+
+/**
+ * Device security levels.
+ */
+@VintfStability
+@Backing(type="int")
+enum SecurityLevel {
+    SOFTWARE = 0,
+    TRUSTED_ENVIRONMENT = 1,
+    /**
+     * STRONGBOX specifies that the secure hardware satisfies the requirements specified in CDD
+     * 9.11.2.
+     */
+    STRONGBOX = 2,
+}
diff --git a/keymaster/aidl/android/hardware/keymaster/VerificationToken.aidl b/keymaster/aidl/android/hardware/keymaster/VerificationToken.aidl
new file mode 100644
index 0000000..eff9ca6
--- /dev/null
+++ b/keymaster/aidl/android/hardware/keymaster/VerificationToken.aidl
@@ -0,0 +1,69 @@
+/*
+ * Copyright 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 android.hardware.keymaster;
+
+import android.hardware.keymaster.SecurityLevel;
+import android.hardware.keymaster.Timestamp;
+import android.hardware.keymaster.HardwareAuthenticatorType;
+
+/**
+ * VerificationToken instances are used for secure environments to authenticate one another.
+ *
+ * This version of the parcelable currently don't use the parametersVerified field since it's not
+ * needed for time-based verification. This can be added in a later version, if needed.
+ */
+@VintfStability
+parcelable VerificationToken {
+    /**
+     * The operation handle, used to ensure freshness.
+     */
+    long challenge;
+
+    /**
+     * The current time of the secure environment that generates the VerificationToken.  This can be
+     * checked against auth tokens generated by the same secure environment, which avoids needing to
+     * synchronize clocks.
+     */
+    Timestamp timestamp;
+
+    /**
+     * SecurityLevel of the secure environment that generated the token.
+     */
+    SecurityLevel securityLevel;
+
+    /**
+     * 32-byte HMAC-SHA256 of the above values, computed as:
+     *
+     *    HMAC(H,
+     *         "Auth Verification" || challenge || timestamp || securityLevel || parametersVerified)
+     *
+     * where:
+     *
+     *   ``HMAC'' is the shared HMAC key (see computeSharedHmac() in IKeymaster).
+     *
+     *   ``||'' represents concatenation
+     *
+     * The representation of challenge and timestamp is as 64-bit unsigned integers in big-endian
+     * order.  securityLevel is represented as a 32-bit unsigned integer in big-endian order.
+     *
+     * If parametersVerified is non-empty, the representation of parametersVerified is an ASN.1 DER
+     * encoded representation of the values.  The ASN.1 schema used is the AuthorizationList schema
+     * from the Keystore attestation documentation.  If parametersVerified is empty, it is simply
+     * omitted from the HMAC computation.
+     */
+    byte[] mac;
+}
diff --git a/media/omx/1.0/vts/functional/common/Android.bp b/media/omx/1.0/vts/functional/common/Android.bp
index 2c024a0..7e7463a 100644
--- a/media/omx/1.0/vts/functional/common/Android.bp
+++ b/media/omx/1.0/vts/functional/common/Android.bp
@@ -68,11 +68,11 @@
         "android.hidl.allocator@1.0",
         "android.hidl.memory@1.0",
         "libhidlmemory",
-        "libnativehelper",
     ],
 
     // TODO(b/64437680): Assume these libs are always available on the device.
     shared_libs: [
+        "libnativehelper",
         "libstagefright_foundation",
     ],
 }
diff --git a/neuralnetworks/1.0/vts/functional/BasicTests.cpp b/neuralnetworks/1.0/vts/functional/BasicTests.cpp
index cc44c9e..bda43b1 100644
--- a/neuralnetworks/1.0/vts/functional/BasicTests.cpp
+++ b/neuralnetworks/1.0/vts/functional/BasicTests.cpp
@@ -18,8 +18,12 @@
 
 #include "VtsHalNeuralnetworks.h"
 
+#include "1.0/Callbacks.h"
+
 namespace android::hardware::neuralnetworks::V1_0::vts::functional {
 
+using implementation::PreparedModelCallback;
+
 // create device test
 TEST_P(NeuralnetworksHidlTest, CreateDevice) {}
 
@@ -43,4 +47,136 @@
     EXPECT_TRUE(ret.isOk());
 }
 
+// detect cycle
+TEST_P(NeuralnetworksHidlTest, CycleTest) {
+    // opnd0 = TENSOR_FLOAT32            // model input
+    // opnd1 = TENSOR_FLOAT32            // model input
+    // opnd2 = INT32                     // model input
+    // opnd3 = ADD(opnd0, opnd4, opnd2)
+    // opnd4 = ADD(opnd1, opnd3, opnd2)
+    // opnd5 = ADD(opnd4, opnd0, opnd2)  // model output
+    //
+    //            +-----+
+    //            |     |
+    //            v     |
+    // 3 = ADD(0, 4, 2) |
+    // |                |
+    // +----------+     |
+    //            |     |
+    //            v     |
+    // 4 = ADD(1, 3, 2) |
+    // |                |
+    // +----------------+
+    // |
+    // |
+    // +-------+
+    //         |
+    //         v
+    // 5 = ADD(4, 0, 2)
+
+    const std::vector<Operand> operands = {
+            {
+                    // operands[0]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 2,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::MODEL_INPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[1]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 1,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::MODEL_INPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[2]
+                    .type = OperandType::INT32,
+                    .dimensions = {},
+                    .numberOfConsumers = 3,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::MODEL_INPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[3]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 1,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::TEMPORARY_VARIABLE,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[4]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 2,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::TEMPORARY_VARIABLE,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[5]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 0,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::MODEL_OUTPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+    };
+
+    const std::vector<Operation> operations = {
+            {.type = OperationType::ADD, .inputs = {0, 4, 2}, .outputs = {3}},
+            {.type = OperationType::ADD, .inputs = {1, 3, 2}, .outputs = {4}},
+            {.type = OperationType::ADD, .inputs = {4, 0, 2}, .outputs = {5}},
+    };
+
+    const Model model = {
+            .operands = operands,
+            .operations = operations,
+            .inputIndexes = {0, 1, 2},
+            .outputIndexes = {5},
+            .operandValues = {},
+            .pools = {},
+    };
+
+    // ensure that getSupportedOperations() checks model validity
+    ErrorStatus supportedOpsErrorStatus = ErrorStatus::GENERAL_FAILURE;
+    Return<void> supportedOpsReturn = kDevice->getSupportedOperations(
+            model, [&model, &supportedOpsErrorStatus](ErrorStatus status,
+                                                      const hidl_vec<bool>& supported) {
+                supportedOpsErrorStatus = status;
+                if (status == ErrorStatus::NONE) {
+                    ASSERT_EQ(supported.size(), model.operations.size());
+                }
+            });
+    ASSERT_TRUE(supportedOpsReturn.isOk());
+    ASSERT_EQ(supportedOpsErrorStatus, ErrorStatus::INVALID_ARGUMENT);
+
+    // ensure that prepareModel() checks model validity
+    sp<PreparedModelCallback> preparedModelCallback = new PreparedModelCallback;
+    Return<ErrorStatus> prepareLaunchReturn = kDevice->prepareModel(model, preparedModelCallback);
+    ASSERT_TRUE(prepareLaunchReturn.isOk());
+    //     Note that preparation can fail for reasons other than an
+    //     invalid model (invalid model should result in
+    //     INVALID_ARGUMENT) -- for example, perhaps not all
+    //     operations are supported, or perhaps the device hit some
+    //     kind of capacity limit.
+    EXPECT_NE(prepareLaunchReturn, ErrorStatus::NONE);
+    EXPECT_NE(preparedModelCallback->getStatus(), ErrorStatus::NONE);
+    EXPECT_EQ(preparedModelCallback->getPreparedModel(), nullptr);
+}
+
 }  // namespace android::hardware::neuralnetworks::V1_0::vts::functional
diff --git a/neuralnetworks/1.0/vts/functional/Utils.cpp b/neuralnetworks/1.0/vts/functional/Utils.cpp
index 3613e69..32850b0 100644
--- a/neuralnetworks/1.0/vts/functional/Utils.cpp
+++ b/neuralnetworks/1.0/vts/functional/Utils.cpp
@@ -29,7 +29,11 @@
 
 #include <gtest/gtest.h>
 #include <algorithm>
+#include <cstring>
+#include <functional>
 #include <iostream>
+#include <map>
+#include <numeric>
 #include <vector>
 
 namespace android::hardware::neuralnetworks {
@@ -172,6 +176,45 @@
     return outputBuffers;
 }
 
+uint32_t sizeOfData(V1_0::OperandType type) {
+    switch (type) {
+        case V1_0::OperandType::FLOAT32:
+        case V1_0::OperandType::INT32:
+        case V1_0::OperandType::UINT32:
+        case V1_0::OperandType::TENSOR_FLOAT32:
+        case V1_0::OperandType::TENSOR_INT32:
+            return 4;
+        case V1_0::OperandType::TENSOR_QUANT8_ASYMM:
+            return 1;
+        default:
+            CHECK(false) << "Invalid OperandType " << static_cast<uint32_t>(type);
+            return 0;
+    }
+}
+
+static bool isTensor(V1_0::OperandType type) {
+    switch (type) {
+        case V1_0::OperandType::FLOAT32:
+        case V1_0::OperandType::INT32:
+        case V1_0::OperandType::UINT32:
+            return false;
+        case V1_0::OperandType::TENSOR_FLOAT32:
+        case V1_0::OperandType::TENSOR_INT32:
+        case V1_0::OperandType::TENSOR_QUANT8_ASYMM:
+            return true;
+        default:
+            CHECK(false) << "Invalid OperandType " << static_cast<uint32_t>(type);
+            return false;
+    }
+}
+
+uint32_t sizeOfData(const V1_0::Operand& operand) {
+    const uint32_t dataSize = sizeOfData(operand.type);
+    if (isTensor(operand.type) && operand.dimensions.size() == 0) return 0;
+    return std::accumulate(operand.dimensions.begin(), operand.dimensions.end(), dataSize,
+                           std::multiplies<>{});
+}
+
 std::string gtestCompliantName(std::string name) {
     // gtest test names must only contain alphanumeric characters
     std::replace_if(
diff --git a/neuralnetworks/1.0/vts/functional/ValidateModel.cpp b/neuralnetworks/1.0/vts/functional/ValidateModel.cpp
index 79d8594..5ffbd43 100644
--- a/neuralnetworks/1.0/vts/functional/ValidateModel.cpp
+++ b/neuralnetworks/1.0/vts/functional/ValidateModel.cpp
@@ -17,9 +17,14 @@
 #define LOG_TAG "neuralnetworks_hidl_hal_test"
 
 #include "1.0/Callbacks.h"
+#include "1.0/Utils.h"
 #include "GeneratedTestHarness.h"
 #include "VtsHalNeuralnetworks.h"
 
+#include <optional>
+#include <type_traits>
+#include <utility>
+
 namespace android::hardware::neuralnetworks::V1_0::vts::functional {
 
 using implementation::PreparedModelCallback;
@@ -67,26 +72,6 @@
     validatePrepareModel(device, message, model);
 }
 
-// Delete element from hidl_vec. hidl_vec doesn't support a "remove" operation,
-// so this is efficiently accomplished by moving the element to the end and
-// resizing the hidl_vec to one less.
-template <typename Type>
-static void hidl_vec_removeAt(hidl_vec<Type>* vec, uint32_t index) {
-    if (vec) {
-        std::rotate(vec->begin() + index, vec->begin() + index + 1, vec->end());
-        vec->resize(vec->size() - 1);
-    }
-}
-
-template <typename Type>
-static uint32_t hidl_vec_push_back(hidl_vec<Type>* vec, const Type& value) {
-    // assume vec is valid
-    const uint32_t index = vec->size();
-    vec->resize(index + 1);
-    (*vec)[index] = value;
-    return index;
-}
-
 static uint32_t addOperand(Model* model) {
     return hidl_vec_push_back(&model->operands,
                               {
@@ -107,6 +92,211 @@
     return index;
 }
 
+// If we introduce a CONSTANT_COPY for an operand of size operandSize,
+// how much will this increase the size of the model?  This assumes
+// that we can (re)use all of model.operandValues for the operand
+// value.
+static size_t constantCopyExtraSize(const Model& model, size_t operandSize) {
+    const size_t operandValuesSize = model.operandValues.size();
+    return (operandValuesSize < operandSize) ? (operandSize - operandValuesSize) : 0;
+}
+
+// Highly specialized utility routine for converting an operand to
+// CONSTANT_COPY lifetime.
+//
+// Expects that:
+// - operand has a known size
+// - operand->lifetime has already been set to CONSTANT_COPY
+// - operand->location has been zeroed out
+//
+// Does the following:
+// - initializes operand->location to point to the beginning of model->operandValues
+// - resizes model->operandValues (if necessary) to be large enough for the operand
+//   value, padding it with zeroes on the end
+//
+// Potential problem:
+// By changing the operand to CONSTANT_COPY lifetime, this function is effectively initializing the
+// operand with unspecified (but deterministic) data. This means that the model may be invalidated
+// in two ways: not only is the lifetime of CONSTANT_COPY invalid, but the operand's value in the
+// graph may also be invalid (e.g., if the operand is used as an activation code and has an invalid
+// value). For now, this should be fine because it just means we're not testing what we think we're
+// testing in certain cases; but we can handwave this and assume we're probabilistically likely to
+// exercise the validation code over the span of the entire test set and operand space.
+//
+// Aborts if the specified operand type is an extension type or OEM type.
+static void becomeConstantCopy(Model* model, Operand* operand) {
+    // sizeOfData will abort if the specified type is an extension type or OEM type.
+    const size_t sizeOfOperand = sizeOfData(*operand);
+    EXPECT_NE(sizeOfOperand, size_t(0));
+    operand->location.poolIndex = 0;
+    operand->location.offset = 0;
+    operand->location.length = sizeOfOperand;
+    if (model->operandValues.size() < sizeOfOperand) {
+        model->operandValues.resize(sizeOfOperand);
+    }
+}
+
+// The sizeForBinder() functions estimate the size of the
+// representation of a value when sent to binder.  It's probably a bit
+// of an under-estimate, because we don't know the size of the
+// metadata in the binder format (e.g., representation of the size of
+// a vector); but at least it adds up "big" things like vector
+// contents.  However, it doesn't treat inter-field or end-of-struct
+// padding in a methodical way -- there's no attempt to be consistent
+// in whether or not padding in the native (C++) representation
+// contributes to the estimated size for the binder representation;
+// and there's no attempt to understand what padding (if any) is
+// needed in the binder representation.
+//
+// This assumes that non-metadata uses a fixed length encoding (e.g.,
+// a uint32_t is always encoded in sizeof(uint32_t) bytes, rather than
+// using an encoding whose length is related to the magnitude of the
+// encoded value).
+
+template <typename Type>
+static size_t sizeForBinder(const Type& val) {
+    static_assert(std::is_trivially_copyable_v<std::remove_reference_t<Type>>,
+                  "expected a trivially copyable type");
+    return sizeof(val);
+}
+
+template <typename Type>
+static size_t sizeForBinder(const hidl_vec<Type>& vec) {
+    return std::accumulate(vec.begin(), vec.end(), 0,
+                           [](size_t acc, const Type& x) { return acc + sizeForBinder(x); });
+}
+
+template <>
+size_t sizeForBinder(const Operand& operand) {
+    size_t size = 0;
+
+    size += sizeForBinder(operand.type);
+    size += sizeForBinder(operand.dimensions);
+    size += sizeForBinder(operand.numberOfConsumers);
+    size += sizeForBinder(operand.scale);
+    size += sizeForBinder(operand.zeroPoint);
+    size += sizeForBinder(operand.lifetime);
+    size += sizeForBinder(operand.location);
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const Operation& operation) {
+    size_t size = 0;
+
+    size += sizeForBinder(operation.type);
+    size += sizeForBinder(operation.inputs);
+    size += sizeForBinder(operation.outputs);
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const hidl_string& name) {
+    return name.size();
+}
+
+template <>
+size_t sizeForBinder(const hidl_memory& memory) {
+    // This is just a guess.
+
+    size_t size = 0;
+
+    if (const native_handle_t* handle = memory.handle()) {
+        size += sizeof(*handle);
+        size += sizeof(handle->data[0] * (handle->numFds + handle->numInts));
+    }
+    size += sizeForBinder(memory.name());
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const Model& model) {
+    size_t size = 0;
+
+    size += sizeForBinder(model.operands);
+    size += sizeForBinder(model.operations);
+    size += sizeForBinder(model.inputIndexes);
+    size += sizeForBinder(model.outputIndexes);
+    size += sizeForBinder(model.operandValues);
+    size += sizeForBinder(model.pools);
+
+    return size;
+}
+
+// https://developer.android.com/reference/android/os/TransactionTooLargeException.html
+//
+//     "The Binder transaction buffer has a limited fixed size,
+//     currently 1Mb, which is shared by all transactions in progress
+//     for the process."
+//
+// Will our representation fit under this limit?  There are two complications:
+// - Our representation size is just approximate (see sizeForBinder()).
+// - This object may not be the only occupant of the Binder transaction buffer.
+// So we'll be very conservative: We want the representation size to be no
+// larger than half the transaction buffer size.
+//
+// If our representation grows large enough that it still fits within
+// the transaction buffer but combined with other transactions may
+// exceed the buffer size, then we may see intermittent HAL transport
+// errors.
+static bool exceedsBinderSizeLimit(size_t representationSize) {
+    // Instead of using this fixed buffer size, we might instead be able to use
+    // ProcessState::self()->getMmapSize(). However, this has a potential
+    // problem: The binder/mmap size of the current process does not necessarily
+    // indicate the binder/mmap size of the service (i.e., the other process).
+    // The only way it would be a good indication is if both the current process
+    // and the service use the default size.
+    static const size_t kHalfBufferSize = 1024 * 1024 / 2;
+
+    return representationSize > kHalfBufferSize;
+}
+
+///////////////////////// VALIDATE EXECUTION ORDER ////////////////////////////
+
+static void mutateExecutionOrderTest(const sp<IDevice>& device, const V1_0::Model& model) {
+    for (size_t operation = 0; operation < model.operations.size(); ++operation) {
+        const Operation& operationObj = model.operations[operation];
+        for (uint32_t input : operationObj.inputs) {
+            if (model.operands[input].lifetime == OperandLifeTime::TEMPORARY_VARIABLE ||
+                model.operands[input].lifetime == OperandLifeTime::MODEL_OUTPUT) {
+                // This operation reads an operand written by some
+                // other operation.  Move this operation to the
+                // beginning of the sequence, ensuring that it reads
+                // the operand before that operand is written, thereby
+                // violating execution order rules.
+                const std::string message = "mutateExecutionOrderTest: operation " +
+                                            std::to_string(operation) + " is a reader";
+                validate(device, message, model, [operation](Model* model) {
+                    auto& operations = model->operations;
+                    std::rotate(operations.begin(), operations.begin() + operation,
+                                operations.begin() + operation + 1);
+                });
+                break;  // only need to do this once per operation
+            }
+        }
+        for (uint32_t output : operationObj.outputs) {
+            if (model.operands[output].numberOfConsumers > 0) {
+                // This operation writes an operand read by some other
+                // operation.  Move this operation to the end of the
+                // sequence, ensuring that it writes the operand after
+                // that operand is read, thereby violating execution
+                // order rules.
+                const std::string message = "mutateExecutionOrderTest: operation " +
+                                            std::to_string(operation) + " is a writer";
+                validate(device, message, model, [operation](Model* model) {
+                    auto& operations = model->operations;
+                    std::rotate(operations.begin() + operation, operations.begin() + operation + 1,
+                                operations.end());
+                });
+                break;  // only need to do this once per operation
+            }
+        }
+    }
+}
+
 ///////////////////////// VALIDATE MODEL OPERAND TYPE /////////////////////////
 
 static const int32_t invalidOperandTypes[] = {
@@ -218,9 +408,233 @@
     }
 }
 
+///////////////////////// VALIDATE OPERAND LIFETIME /////////////////////////////////////////////
+
+static std::vector<OperandLifeTime> getInvalidLifeTimes(const Model& model, size_t modelSize,
+                                                        const Operand& operand) {
+    // TODO: Support OperandLifeTime::CONSTANT_REFERENCE as an invalid lifetime
+    // TODO: Support OperandLifeTime::NO_VALUE as an invalid lifetime
+
+    // Ways to get an invalid lifetime:
+    // - change whether a lifetime means an operand should have a writer
+    std::vector<OperandLifeTime> ret;
+    switch (operand.lifetime) {
+        case OperandLifeTime::MODEL_OUTPUT:
+        case OperandLifeTime::TEMPORARY_VARIABLE:
+            ret = {
+                    OperandLifeTime::MODEL_INPUT,
+                    OperandLifeTime::CONSTANT_COPY,
+            };
+            break;
+        case OperandLifeTime::CONSTANT_COPY:
+        case OperandLifeTime::CONSTANT_REFERENCE:
+        case OperandLifeTime::MODEL_INPUT:
+            ret = {
+                    OperandLifeTime::TEMPORARY_VARIABLE,
+                    OperandLifeTime::MODEL_OUTPUT,
+            };
+            break;
+        case OperandLifeTime::NO_VALUE:
+            // Not enough information to know whether
+            // TEMPORARY_VARIABLE or CONSTANT_COPY would be invalid --
+            // is this operand written (then CONSTANT_COPY would be
+            // invalid) or not (then TEMPORARY_VARIABLE would be
+            // invalid)?
+            break;
+        default:
+            ADD_FAILURE();
+            break;
+    }
+
+    const size_t operandSize = sizeOfData(operand);  // will be zero if shape is unknown
+    if (!operandSize ||
+        exceedsBinderSizeLimit(modelSize + constantCopyExtraSize(model, operandSize))) {
+        // Unknown size or too-large size
+        ret.erase(std::remove(ret.begin(), ret.end(), OperandLifeTime::CONSTANT_COPY), ret.end());
+    }
+
+    return ret;
+}
+
+static void mutateOperandLifeTimeTest(const sp<IDevice>& device, const V1_0::Model& model) {
+    const size_t modelSize = sizeForBinder(model);
+    for (size_t operand = 0; operand < model.operands.size(); ++operand) {
+        const std::vector<OperandLifeTime> invalidLifeTimes =
+                getInvalidLifeTimes(model, modelSize, model.operands[operand]);
+        for (OperandLifeTime invalidLifeTime : invalidLifeTimes) {
+            const std::string message = "mutateOperandLifetimeTest: operand " +
+                                        std::to_string(operand) + " has lifetime " +
+                                        toString(invalidLifeTime) + " instead of lifetime " +
+                                        toString(model.operands[operand].lifetime);
+            validate(device, message, model, [operand, invalidLifeTime](Model* model) {
+                static const DataLocation kZeroDataLocation = {};
+                Operand& operandObj = model->operands[operand];
+                switch (operandObj.lifetime) {
+                    case OperandLifeTime::MODEL_INPUT: {
+                        hidl_vec_remove(&model->inputIndexes, uint32_t(operand));
+                        break;
+                    }
+                    case OperandLifeTime::MODEL_OUTPUT: {
+                        hidl_vec_remove(&model->outputIndexes, uint32_t(operand));
+                        break;
+                    }
+                    default:
+                        break;
+                }
+                operandObj.lifetime = invalidLifeTime;
+                operandObj.location = kZeroDataLocation;
+                switch (invalidLifeTime) {
+                    case OperandLifeTime::CONSTANT_COPY: {
+                        becomeConstantCopy(model, &operandObj);
+                        break;
+                    }
+                    case OperandLifeTime::MODEL_INPUT:
+                        hidl_vec_push_back(&model->inputIndexes, uint32_t(operand));
+                        break;
+                    case OperandLifeTime::MODEL_OUTPUT:
+                        hidl_vec_push_back(&model->outputIndexes, uint32_t(operand));
+                        break;
+                    default:
+                        break;
+                }
+            });
+        }
+    }
+}
+
+///////////////////////// VALIDATE OPERAND INPUT-or-OUTPUT //////////////////////////////////////
+
+static std::optional<OperandLifeTime> getInputOutputLifeTime(const Model& model, size_t modelSize,
+                                                             const Operand& operand) {
+    // Ways to get an invalid lifetime (with respect to model inputIndexes and outputIndexes):
+    // - change whether a lifetime means an operand is a model input, a model output, or neither
+    // - preserve whether or not a lifetime means an operand should have a writer
+    switch (operand.lifetime) {
+        case OperandLifeTime::CONSTANT_COPY:
+        case OperandLifeTime::CONSTANT_REFERENCE:
+            return OperandLifeTime::MODEL_INPUT;
+        case OperandLifeTime::MODEL_INPUT: {
+            const size_t operandSize = sizeOfData(operand);  // will be zero if shape is unknown
+            if (!operandSize ||
+                exceedsBinderSizeLimit(modelSize + constantCopyExtraSize(model, operandSize))) {
+                // Unknown size or too-large size
+                break;
+            }
+            return OperandLifeTime::CONSTANT_COPY;
+        }
+        case OperandLifeTime::MODEL_OUTPUT:
+            return OperandLifeTime::TEMPORARY_VARIABLE;
+        case OperandLifeTime::TEMPORARY_VARIABLE:
+            return OperandLifeTime::MODEL_OUTPUT;
+        case OperandLifeTime::NO_VALUE:
+            // Not enough information to know whether
+            // TEMPORARY_VARIABLE or CONSTANT_COPY would be an
+            // appropriate choice -- is this operand written (then
+            // TEMPORARY_VARIABLE would be appropriate) or not (then
+            // CONSTANT_COPY would be appropriate)?
+            break;
+        default:
+            ADD_FAILURE();
+            break;
+    }
+
+    return std::nullopt;
+}
+
+static void mutateOperandInputOutputTest(const sp<IDevice>& device, const V1_0::Model& model) {
+    const size_t modelSize = sizeForBinder(model);
+    for (size_t operand = 0; operand < model.operands.size(); ++operand) {
+        const std::optional<OperandLifeTime> changedLifeTime =
+                getInputOutputLifeTime(model, modelSize, model.operands[operand]);
+        if (changedLifeTime) {
+            const std::string message = "mutateOperandInputOutputTest: operand " +
+                                        std::to_string(operand) + " has lifetime " +
+                                        toString(*changedLifeTime) + " instead of lifetime " +
+                                        toString(model.operands[operand].lifetime);
+            validate(device, message, model, [operand, changedLifeTime](Model* model) {
+                static const DataLocation kZeroDataLocation = {};
+                Operand& operandObj = model->operands[operand];
+                operandObj.lifetime = *changedLifeTime;
+                operandObj.location = kZeroDataLocation;
+                if (*changedLifeTime == OperandLifeTime::CONSTANT_COPY) {
+                    becomeConstantCopy(model, &operandObj);
+                }
+            });
+        }
+    }
+}
+
+///////////////////////// VALIDATE OPERAND NUMBER OF CONSUMERS //////////////////////////////////
+
+static std::vector<uint32_t> getInvalidNumberOfConsumers(uint32_t numberOfConsumers) {
+    if (numberOfConsumers == 0) {
+        return {1};
+    } else {
+        return {numberOfConsumers - 1, numberOfConsumers + 1};
+    }
+}
+
+static void mutateOperandNumberOfConsumersTest(const sp<IDevice>& device,
+                                               const V1_0::Model& model) {
+    for (size_t operand = 0; operand < model.operands.size(); ++operand) {
+        const std::vector<uint32_t> invalidNumberOfConsumersVec =
+                getInvalidNumberOfConsumers(model.operands[operand].numberOfConsumers);
+        for (uint32_t invalidNumberOfConsumers : invalidNumberOfConsumersVec) {
+            const std::string message =
+                    "mutateOperandNumberOfConsumersTest: operand " + std::to_string(operand) +
+                    " numberOfConsumers = " + std::to_string(invalidNumberOfConsumers);
+            validate(device, message, model, [operand, invalidNumberOfConsumers](Model* model) {
+                model->operands[operand].numberOfConsumers = invalidNumberOfConsumers;
+            });
+        }
+    }
+}
+
+///////////////////////// VALIDATE OPERAND NUMBER OF WRITERS ////////////////////////////////////
+
+static void mutateOperandAddWriterTest(const sp<IDevice>& device, const V1_0::Model& model) {
+    for (size_t operation = 0; operation < model.operations.size(); ++operation) {
+        for (size_t badOutputNum = 0; badOutputNum < model.operations[operation].outputs.size();
+             ++badOutputNum) {
+            const uint32_t outputOperandIndex = model.operations[operation].outputs[badOutputNum];
+            const std::string message = "mutateOperandAddWriterTest: operation " +
+                                        std::to_string(operation) + " writes to " +
+                                        std::to_string(outputOperandIndex);
+            // We'll insert a copy of the operation, all of whose
+            // OTHER output operands are newly-created -- i.e.,
+            // there'll only be a duplicate write of ONE of that
+            // operation's output operands.
+            validate(device, message, model, [operation, badOutputNum](Model* model) {
+                Operation newOperation = model->operations[operation];
+                for (uint32_t input : newOperation.inputs) {
+                    ++model->operands[input].numberOfConsumers;
+                }
+                for (size_t outputNum = 0; outputNum < newOperation.outputs.size(); ++outputNum) {
+                    if (outputNum == badOutputNum) continue;
+
+                    Operand operandValue = model->operands[newOperation.outputs[outputNum]];
+                    operandValue.numberOfConsumers = 0;
+                    if (operandValue.lifetime == OperandLifeTime::MODEL_OUTPUT) {
+                        operandValue.lifetime = OperandLifeTime::TEMPORARY_VARIABLE;
+                    } else {
+                        ASSERT_EQ(operandValue.lifetime, OperandLifeTime::TEMPORARY_VARIABLE);
+                    }
+                    newOperation.outputs[outputNum] =
+                            hidl_vec_push_back(&model->operands, operandValue);
+                }
+                // Where do we insert the extra writer (a new
+                // operation)?  It has to be later than all the
+                // writers of its inputs.  The easiest thing to do
+                // is to insert it at the end of the operation
+                // sequence.
+                hidl_vec_push_back(&model->operations, newOperation);
+            });
+        }
+    }
+}
+
 ///////////////////////// VALIDATE EXTRA ??? /////////////////////////
 
-// TODO: Operand::lifetime
 // TODO: Operand::location
 
 ///////////////////////// VALIDATE OPERATION OPERAND TYPE /////////////////////////
@@ -351,6 +765,33 @@
     }
 }
 
+///////////////////////// VALIDATE MODEL OPERANDS WRITTEN ///////////////////////////////////////
+
+static void mutateOperationRemoveWriteTest(const sp<IDevice>& device, const V1_0::Model& model) {
+    for (size_t operation = 0; operation < model.operations.size(); ++operation) {
+        for (size_t outputNum = 0; outputNum < model.operations[operation].outputs.size();
+             ++outputNum) {
+            const uint32_t outputOperandIndex = model.operations[operation].outputs[outputNum];
+            if (model.operands[outputOperandIndex].numberOfConsumers > 0) {
+                const std::string message = "mutateOperationRemoveWriteTest: operation " +
+                                            std::to_string(operation) + " writes to " +
+                                            std::to_string(outputOperandIndex);
+                validate(device, message, model, [operation, outputNum](Model* model) {
+                    uint32_t& outputOperandIndex = model->operations[operation].outputs[outputNum];
+                    Operand operandValue = model->operands[outputOperandIndex];
+                    operandValue.numberOfConsumers = 0;
+                    if (operandValue.lifetime == OperandLifeTime::MODEL_OUTPUT) {
+                        operandValue.lifetime = OperandLifeTime::TEMPORARY_VARIABLE;
+                    } else {
+                        ASSERT_EQ(operandValue.lifetime, OperandLifeTime::TEMPORARY_VARIABLE);
+                    }
+                    outputOperandIndex = hidl_vec_push_back(&model->operands, operandValue);
+                });
+            }
+        }
+    }
+}
+
 ///////////////////////// REMOVE OPERAND FROM EVERYTHING /////////////////////////
 
 static void removeValueAndDecrementGreaterValues(hidl_vec<uint32_t>* vec, uint32_t value) {
@@ -476,14 +917,20 @@
 ////////////////////////// ENTRY POINT //////////////////////////////
 
 void validateModel(const sp<IDevice>& device, const Model& model) {
+    mutateExecutionOrderTest(device, model);
     mutateOperandTypeTest(device, model);
     mutateOperandRankTest(device, model);
     mutateOperandScaleTest(device, model);
     mutateOperandZeroPointTest(device, model);
+    mutateOperandLifeTimeTest(device, model);
+    mutateOperandInputOutputTest(device, model);
+    mutateOperandNumberOfConsumersTest(device, model);
+    mutateOperandAddWriterTest(device, model);
     mutateOperationOperandTypeTest(device, model);
     mutateOperationTypeTest(device, model);
     mutateOperationInputOperandIndexTest(device, model);
     mutateOperationOutputOperandIndexTest(device, model);
+    mutateOperationRemoveWriteTest(device, model);
     removeOperandTest(device, model);
     removeOperationTest(device, model);
     removeOperationInputTest(device, model);
diff --git a/neuralnetworks/1.0/vts/functional/include/1.0/Utils.h b/neuralnetworks/1.0/vts/functional/include/1.0/Utils.h
index 3292f79..7bd0460 100644
--- a/neuralnetworks/1.0/vts/functional/include/1.0/Utils.h
+++ b/neuralnetworks/1.0/vts/functional/include/1.0/Utils.h
@@ -21,6 +21,7 @@
 #include <android/hardware/neuralnetworks/1.0/types.h>
 #include <android/hardware_buffer.h>
 #include <android/hidl/memory/1.0/IMemory.h>
+#include <gtest/gtest.h>
 #include <algorithm>
 #include <iosfwd>
 #include <string>
@@ -108,6 +109,15 @@
     vec->resize(vec->size() - 1);
 }
 
+// Assumes there is exactly one instance of the value in the vector.
+template <typename Type>
+inline void hidl_vec_remove(hidl_vec<Type>* vec, const Type& val) {
+    CHECK(vec != nullptr);
+    auto where = std::find(vec->begin(), vec->end(), val);
+    ASSERT_NE(where, vec->end());
+    hidl_vec_removeAt(vec, where - vec->begin());
+}
+
 template <typename Type>
 inline uint32_t hidl_vec_push_back(hidl_vec<Type>* vec, const Type& value) {
     CHECK(vec != nullptr);
@@ -117,6 +127,18 @@
     return index;
 }
 
+// Returns the amount of space needed to store a value of the specified type.
+//
+// Aborts if the specified type is an extension type or OEM type.
+uint32_t sizeOfData(V1_0::OperandType type);
+
+// Returns the amount of space needed to store a value of the dimensions and
+// type of this operand. For a non-extension, non-OEM tensor with unspecified
+// rank or at least one unspecified dimension, returns zero.
+//
+// Aborts if the specified type is an extension type or OEM type.
+uint32_t sizeOfData(const V1_0::Operand& operand);
+
 template <typename Type>
 using Named = std::pair<std::string, Type>;
 
diff --git a/neuralnetworks/1.1/vts/functional/BasicTests.cpp b/neuralnetworks/1.1/vts/functional/BasicTests.cpp
index 44836f0..baadd1b 100644
--- a/neuralnetworks/1.1/vts/functional/BasicTests.cpp
+++ b/neuralnetworks/1.1/vts/functional/BasicTests.cpp
@@ -18,10 +18,16 @@
 
 #include "VtsHalNeuralnetworks.h"
 
+#include "1.0/Callbacks.h"
+
 namespace android::hardware::neuralnetworks::V1_1::vts::functional {
 
 using V1_0::DeviceStatus;
 using V1_0::ErrorStatus;
+using V1_0::Operand;
+using V1_0::OperandLifeTime;
+using V1_0::OperandType;
+using V1_0::implementation::PreparedModelCallback;
 
 // create device test
 TEST_P(NeuralnetworksHidlTest, CreateDevice) {}
@@ -48,4 +54,137 @@
     EXPECT_TRUE(ret.isOk());
 }
 
+// detect cycle
+TEST_P(NeuralnetworksHidlTest, CycleTest) {
+    // opnd0 = TENSOR_FLOAT32            // model input
+    // opnd1 = TENSOR_FLOAT32            // model input
+    // opnd2 = INT32                     // model input
+    // opnd3 = ADD(opnd0, opnd4, opnd2)
+    // opnd4 = ADD(opnd1, opnd3, opnd2)
+    // opnd5 = ADD(opnd4, opnd0, opnd2)  // model output
+    //
+    //            +-----+
+    //            |     |
+    //            v     |
+    // 3 = ADD(0, 4, 2) |
+    // |                |
+    // +----------+     |
+    //            |     |
+    //            v     |
+    // 4 = ADD(1, 3, 2) |
+    // |                |
+    // +----------------+
+    // |
+    // |
+    // +-------+
+    //         |
+    //         v
+    // 5 = ADD(4, 0, 2)
+
+    const std::vector<Operand> operands = {
+            {
+                    // operands[0]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 2,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::MODEL_INPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[1]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 1,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::MODEL_INPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[2]
+                    .type = OperandType::INT32,
+                    .dimensions = {},
+                    .numberOfConsumers = 3,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::MODEL_INPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[3]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 1,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::TEMPORARY_VARIABLE,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[4]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 2,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::TEMPORARY_VARIABLE,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[5]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 0,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::MODEL_OUTPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+    };
+
+    const std::vector<Operation> operations = {
+            {.type = OperationType::ADD, .inputs = {0, 4, 2}, .outputs = {3}},
+            {.type = OperationType::ADD, .inputs = {1, 3, 2}, .outputs = {4}},
+            {.type = OperationType::ADD, .inputs = {4, 0, 2}, .outputs = {5}},
+    };
+
+    const Model model = {
+            .operands = operands,
+            .operations = operations,
+            .inputIndexes = {0, 1, 2},
+            .outputIndexes = {5},
+            .operandValues = {},
+            .pools = {},
+    };
+
+    // ensure that getSupportedOperations_1_1() checks model validity
+    ErrorStatus supportedOpsErrorStatus = ErrorStatus::GENERAL_FAILURE;
+    Return<void> supportedOpsReturn = kDevice->getSupportedOperations_1_1(
+            model, [&model, &supportedOpsErrorStatus](ErrorStatus status,
+                                                      const hidl_vec<bool>& supported) {
+                supportedOpsErrorStatus = status;
+                if (status == ErrorStatus::NONE) {
+                    ASSERT_EQ(supported.size(), model.operations.size());
+                }
+            });
+    ASSERT_TRUE(supportedOpsReturn.isOk());
+    ASSERT_EQ(supportedOpsErrorStatus, ErrorStatus::INVALID_ARGUMENT);
+
+    // ensure that prepareModel_1_1() checks model validity
+    sp<PreparedModelCallback> preparedModelCallback = new PreparedModelCallback;
+    Return<ErrorStatus> prepareLaunchReturn = kDevice->prepareModel_1_1(
+            model, ExecutionPreference::FAST_SINGLE_ANSWER, preparedModelCallback);
+    ASSERT_TRUE(prepareLaunchReturn.isOk());
+    //     Note that preparation can fail for reasons other than an
+    //     invalid model (invalid model should result in
+    //     INVALID_ARGUMENT) -- for example, perhaps not all
+    //     operations are supported, or perhaps the device hit some
+    //     kind of capacity limit.
+    EXPECT_NE(prepareLaunchReturn, ErrorStatus::NONE);
+    EXPECT_NE(preparedModelCallback->getStatus(), ErrorStatus::NONE);
+    EXPECT_EQ(preparedModelCallback->getPreparedModel(), nullptr);
+}
+
 }  // namespace android::hardware::neuralnetworks::V1_1::vts::functional
diff --git a/neuralnetworks/1.1/vts/functional/ValidateModel.cpp b/neuralnetworks/1.1/vts/functional/ValidateModel.cpp
index 3b6f0f8..1f4e4ed 100644
--- a/neuralnetworks/1.1/vts/functional/ValidateModel.cpp
+++ b/neuralnetworks/1.1/vts/functional/ValidateModel.cpp
@@ -16,13 +16,19 @@
 
 #define LOG_TAG "neuralnetworks_hidl_hal_test"
 
+#include <android/hardware/neuralnetworks/1.1/types.h>
 #include "1.0/Callbacks.h"
 #include "1.0/Utils.h"
 #include "GeneratedTestHarness.h"
 #include "VtsHalNeuralnetworks.h"
 
+#include <optional>
+#include <type_traits>
+#include <utility>
+
 namespace android::hardware::neuralnetworks::V1_1::vts::functional {
 
+using V1_0::DataLocation;
 using V1_0::ErrorStatus;
 using V1_0::IPreparedModel;
 using V1_0::Operand;
@@ -105,6 +111,212 @@
     return index;
 }
 
+// If we introduce a CONSTANT_COPY for an operand of size operandSize,
+// how much will this increase the size of the model?  This assumes
+// that we can (re)use all of model.operandValues for the operand
+// value.
+static size_t constantCopyExtraSize(const Model& model, size_t operandSize) {
+    const size_t operandValuesSize = model.operandValues.size();
+    return (operandValuesSize < operandSize) ? (operandSize - operandValuesSize) : 0;
+}
+
+// Highly specialized utility routine for converting an operand to
+// CONSTANT_COPY lifetime.
+//
+// Expects that:
+// - operand has a known size
+// - operand->lifetime has already been set to CONSTANT_COPY
+// - operand->location has been zeroed out
+//
+// Does the following:
+// - initializes operand->location to point to the beginning of model->operandValues
+// - resizes model->operandValues (if necessary) to be large enough for the operand
+//   value, padding it with zeroes on the end
+//
+// Potential problem:
+// By changing the operand to CONSTANT_COPY lifetime, this function is effectively initializing the
+// operand with unspecified (but deterministic) data. This means that the model may be invalidated
+// in two ways: not only is the lifetime of CONSTANT_COPY invalid, but the operand's value in the
+// graph may also be invalid (e.g., if the operand is used as an activation code and has an invalid
+// value). For now, this should be fine because it just means we're not testing what we think we're
+// testing in certain cases; but we can handwave this and assume we're probabilistically likely to
+// exercise the validation code over the span of the entire test set and operand space.
+//
+// Aborts if the specified operand type is an extension type or OEM type.
+static void becomeConstantCopy(Model* model, Operand* operand) {
+    // sizeOfData will abort if the specified type is an extension type or OEM type.
+    const size_t sizeOfOperand = sizeOfData(*operand);
+    EXPECT_NE(sizeOfOperand, size_t(0));
+    operand->location.poolIndex = 0;
+    operand->location.offset = 0;
+    operand->location.length = sizeOfOperand;
+    if (model->operandValues.size() < sizeOfOperand) {
+        model->operandValues.resize(sizeOfOperand);
+    }
+}
+
+// The sizeForBinder() functions estimate the size of the
+// representation of a value when sent to binder.  It's probably a bit
+// of an under-estimate, because we don't know the size of the
+// metadata in the binder format (e.g., representation of the size of
+// a vector); but at least it adds up "big" things like vector
+// contents.  However, it doesn't treat inter-field or end-of-struct
+// padding in a methodical way -- there's no attempt to be consistent
+// in whether or not padding in the native (C++) representation
+// contributes to the estimated size for the binder representation;
+// and there's no attempt to understand what padding (if any) is
+// needed in the binder representation.
+//
+// This assumes that non-metadata uses a fixed length encoding (e.g.,
+// a uint32_t is always encoded in sizeof(uint32_t) bytes, rather than
+// using an encoding whose length is related to the magnitude of the
+// encoded value).
+
+template <typename Type>
+static size_t sizeForBinder(const Type& val) {
+    static_assert(std::is_trivially_copyable_v<std::remove_reference_t<Type>>,
+                  "expected a trivially copyable type");
+    return sizeof(val);
+}
+
+template <typename Type>
+static size_t sizeForBinder(const hidl_vec<Type>& vec) {
+    return std::accumulate(vec.begin(), vec.end(), 0,
+                           [](size_t acc, const Type& x) { return acc + sizeForBinder(x); });
+}
+
+template <>
+size_t sizeForBinder(const Operand& operand) {
+    size_t size = 0;
+
+    size += sizeForBinder(operand.type);
+    size += sizeForBinder(operand.dimensions);
+    size += sizeForBinder(operand.numberOfConsumers);
+    size += sizeForBinder(operand.scale);
+    size += sizeForBinder(operand.zeroPoint);
+    size += sizeForBinder(operand.lifetime);
+    size += sizeForBinder(operand.location);
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const Operation& operation) {
+    size_t size = 0;
+
+    size += sizeForBinder(operation.type);
+    size += sizeForBinder(operation.inputs);
+    size += sizeForBinder(operation.outputs);
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const hidl_string& name) {
+    return name.size();
+}
+
+template <>
+size_t sizeForBinder(const hidl_memory& memory) {
+    // This is just a guess.
+
+    size_t size = 0;
+
+    if (const native_handle_t* handle = memory.handle()) {
+        size += sizeof(*handle);
+        size += sizeof(handle->data[0] * (handle->numFds + handle->numInts));
+    }
+    size += sizeForBinder(memory.name());
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const Model& model) {
+    size_t size = 0;
+
+    size += sizeForBinder(model.operands);
+    size += sizeForBinder(model.operations);
+    size += sizeForBinder(model.inputIndexes);
+    size += sizeForBinder(model.outputIndexes);
+    size += sizeForBinder(model.operandValues);
+    size += sizeForBinder(model.pools);
+    size += sizeForBinder(model.relaxComputationFloat32toFloat16);
+
+    return size;
+}
+
+// https://developer.android.com/reference/android/os/TransactionTooLargeException.html
+//
+//     "The Binder transaction buffer has a limited fixed size,
+//     currently 1Mb, which is shared by all transactions in progress
+//     for the process."
+//
+// Will our representation fit under this limit?  There are two complications:
+// - Our representation size is just approximate (see sizeForBinder()).
+// - This object may not be the only occupant of the Binder transaction buffer.
+// So we'll be very conservative: We want the representation size to be no
+// larger than half the transaction buffer size.
+//
+// If our representation grows large enough that it still fits within
+// the transaction buffer but combined with other transactions may
+// exceed the buffer size, then we may see intermittent HAL transport
+// errors.
+static bool exceedsBinderSizeLimit(size_t representationSize) {
+    // Instead of using this fixed buffer size, we might instead be able to use
+    // ProcessState::self()->getMmapSize(). However, this has a potential
+    // problem: The binder/mmap size of the current process does not necessarily
+    // indicate the binder/mmap size of the service (i.e., the other process).
+    // The only way it would be a good indication is if both the current process
+    // and the service use the default size.
+    static const size_t kHalfBufferSize = 1024 * 1024 / 2;
+
+    return representationSize > kHalfBufferSize;
+}
+
+///////////////////////// VALIDATE EXECUTION ORDER ////////////////////////////
+
+static void mutateExecutionOrderTest(const sp<IDevice>& device, const V1_1::Model& model) {
+    for (size_t operation = 0; operation < model.operations.size(); ++operation) {
+        const Operation& operationObj = model.operations[operation];
+        for (uint32_t input : operationObj.inputs) {
+            if (model.operands[input].lifetime == OperandLifeTime::TEMPORARY_VARIABLE ||
+                model.operands[input].lifetime == OperandLifeTime::MODEL_OUTPUT) {
+                // This operation reads an operand written by some
+                // other operation.  Move this operation to the
+                // beginning of the sequence, ensuring that it reads
+                // the operand before that operand is written, thereby
+                // violating execution order rules.
+                const std::string message = "mutateExecutionOrderTest: operation " +
+                                            std::to_string(operation) + " is a reader";
+                validate(device, message, model, [operation](Model* model, ExecutionPreference*) {
+                    auto& operations = model->operations;
+                    std::rotate(operations.begin(), operations.begin() + operation,
+                                operations.begin() + operation + 1);
+                });
+                break;  // only need to do this once per operation
+            }
+        }
+        for (uint32_t output : operationObj.outputs) {
+            if (model.operands[output].numberOfConsumers > 0) {
+                // This operation writes an operand read by some other
+                // operation.  Move this operation to the end of the
+                // sequence, ensuring that it writes the operand after
+                // that operand is read, thereby violating execution
+                // order rules.
+                const std::string message = "mutateExecutionOrderTest: operation " +
+                                            std::to_string(operation) + " is a writer";
+                validate(device, message, model, [operation](Model* model, ExecutionPreference*) {
+                    auto& operations = model->operations;
+                    std::rotate(operations.begin() + operation, operations.begin() + operation + 1,
+                                operations.end());
+                });
+                break;  // only need to do this once per operation
+            }
+        }
+    }
+}
+
 ///////////////////////// VALIDATE MODEL OPERAND TYPE /////////////////////////
 
 static const int32_t invalidOperandTypes[] = {
@@ -221,9 +433,240 @@
     }
 }
 
+///////////////////////// VALIDATE OPERAND LIFETIME /////////////////////////////////////////////
+
+static std::vector<OperandLifeTime> getInvalidLifeTimes(const Model& model, size_t modelSize,
+                                                        const Operand& operand) {
+    // TODO: Support OperandLifeTime::CONSTANT_REFERENCE as an invalid lifetime
+    // TODO: Support OperandLifeTime::NO_VALUE as an invalid lifetime
+
+    // Ways to get an invalid lifetime:
+    // - change whether a lifetime means an operand should have a writer
+    std::vector<OperandLifeTime> ret;
+    switch (operand.lifetime) {
+        case OperandLifeTime::MODEL_OUTPUT:
+        case OperandLifeTime::TEMPORARY_VARIABLE:
+            ret = {
+                    OperandLifeTime::MODEL_INPUT,
+                    OperandLifeTime::CONSTANT_COPY,
+            };
+            break;
+        case OperandLifeTime::CONSTANT_COPY:
+        case OperandLifeTime::CONSTANT_REFERENCE:
+        case OperandLifeTime::MODEL_INPUT:
+            ret = {
+                    OperandLifeTime::TEMPORARY_VARIABLE,
+                    OperandLifeTime::MODEL_OUTPUT,
+            };
+            break;
+        case OperandLifeTime::NO_VALUE:
+            // Not enough information to know whether
+            // TEMPORARY_VARIABLE or CONSTANT_COPY would be invalid --
+            // is this operand written (then CONSTANT_COPY would be
+            // invalid) or not (then TEMPORARY_VARIABLE would be
+            // invalid)?
+            break;
+        default:
+            ADD_FAILURE();
+            break;
+    }
+
+    const size_t operandSize = sizeOfData(operand);  // will be zero if shape is unknown
+    if (!operandSize ||
+        exceedsBinderSizeLimit(modelSize + constantCopyExtraSize(model, operandSize))) {
+        // Unknown size or too-large size
+        ret.erase(std::remove(ret.begin(), ret.end(), OperandLifeTime::CONSTANT_COPY), ret.end());
+    }
+
+    return ret;
+}
+
+static void mutateOperandLifeTimeTest(const sp<IDevice>& device, const V1_1::Model& model) {
+    const size_t modelSize = sizeForBinder(model);
+    for (size_t operand = 0; operand < model.operands.size(); ++operand) {
+        const std::vector<OperandLifeTime> invalidLifeTimes =
+                getInvalidLifeTimes(model, modelSize, model.operands[operand]);
+        for (OperandLifeTime invalidLifeTime : invalidLifeTimes) {
+            const std::string message = "mutateOperandLifetimeTest: operand " +
+                                        std::to_string(operand) + " has lifetime " +
+                                        toString(invalidLifeTime) + " instead of lifetime " +
+                                        toString(model.operands[operand].lifetime);
+            validate(device, message, model,
+                     [operand, invalidLifeTime](Model* model, ExecutionPreference*) {
+                         static const DataLocation kZeroDataLocation = {};
+                         Operand& operandObj = model->operands[operand];
+                         switch (operandObj.lifetime) {
+                             case OperandLifeTime::MODEL_INPUT: {
+                                 hidl_vec_remove(&model->inputIndexes, uint32_t(operand));
+                                 break;
+                             }
+                             case OperandLifeTime::MODEL_OUTPUT: {
+                                 hidl_vec_remove(&model->outputIndexes, uint32_t(operand));
+                                 break;
+                             }
+                             default:
+                                 break;
+                         }
+                         operandObj.lifetime = invalidLifeTime;
+                         operandObj.location = kZeroDataLocation;
+                         switch (invalidLifeTime) {
+                             case OperandLifeTime::CONSTANT_COPY: {
+                                 becomeConstantCopy(model, &operandObj);
+                                 break;
+                             }
+                             case OperandLifeTime::MODEL_INPUT:
+                                 hidl_vec_push_back(&model->inputIndexes, uint32_t(operand));
+                                 break;
+                             case OperandLifeTime::MODEL_OUTPUT:
+                                 hidl_vec_push_back(&model->outputIndexes, uint32_t(operand));
+                                 break;
+                             default:
+                                 break;
+                         }
+                     });
+        }
+    }
+}
+
+///////////////////////// VALIDATE OPERAND INPUT-or-OUTPUT //////////////////////////////////////
+
+static std::optional<OperandLifeTime> getInputOutputLifeTime(const Model& model, size_t modelSize,
+                                                             const Operand& operand) {
+    // Ways to get an invalid lifetime (with respect to model inputIndexes and outputIndexes):
+    // - change whether a lifetime means an operand is a model input, a model output, or neither
+    // - preserve whether or not a lifetime means an operand should have a writer
+    switch (operand.lifetime) {
+        case OperandLifeTime::CONSTANT_COPY:
+        case OperandLifeTime::CONSTANT_REFERENCE:
+            return OperandLifeTime::MODEL_INPUT;
+        case OperandLifeTime::MODEL_INPUT: {
+            const size_t operandSize = sizeOfData(operand);  // will be zero if shape is unknown
+            if (!operandSize ||
+                exceedsBinderSizeLimit(modelSize + constantCopyExtraSize(model, operandSize))) {
+                // Unknown size or too-large size
+                break;
+            }
+            return OperandLifeTime::CONSTANT_COPY;
+        }
+        case OperandLifeTime::MODEL_OUTPUT:
+            return OperandLifeTime::TEMPORARY_VARIABLE;
+        case OperandLifeTime::TEMPORARY_VARIABLE:
+            return OperandLifeTime::MODEL_OUTPUT;
+        case OperandLifeTime::NO_VALUE:
+            // Not enough information to know whether
+            // TEMPORARY_VARIABLE or CONSTANT_COPY would be an
+            // appropriate choice -- is this operand written (then
+            // TEMPORARY_VARIABLE would be appropriate) or not (then
+            // CONSTANT_COPY would be appropriate)?
+            break;
+        default:
+            ADD_FAILURE();
+            break;
+    }
+
+    return std::nullopt;
+}
+
+static void mutateOperandInputOutputTest(const sp<IDevice>& device, const V1_1::Model& model) {
+    const size_t modelSize = sizeForBinder(model);
+    for (size_t operand = 0; operand < model.operands.size(); ++operand) {
+        const std::optional<OperandLifeTime> changedLifeTime =
+                getInputOutputLifeTime(model, modelSize, model.operands[operand]);
+        if (changedLifeTime) {
+            const std::string message = "mutateOperandInputOutputTest: operand " +
+                                        std::to_string(operand) + " has lifetime " +
+                                        toString(*changedLifeTime) + " instead of lifetime " +
+                                        toString(model.operands[operand].lifetime);
+            validate(device, message, model,
+                     [operand, changedLifeTime](Model* model, ExecutionPreference*) {
+                         static const DataLocation kZeroDataLocation = {};
+                         Operand& operandObj = model->operands[operand];
+                         operandObj.lifetime = *changedLifeTime;
+                         operandObj.location = kZeroDataLocation;
+                         if (*changedLifeTime == OperandLifeTime::CONSTANT_COPY) {
+                             becomeConstantCopy(model, &operandObj);
+                         }
+                     });
+        }
+    }
+}
+
+///////////////////////// VALIDATE OPERAND NUMBER OF CONSUMERS //////////////////////////////////
+
+static std::vector<uint32_t> getInvalidNumberOfConsumers(uint32_t numberOfConsumers) {
+    if (numberOfConsumers == 0) {
+        return {1};
+    } else {
+        return {numberOfConsumers - 1, numberOfConsumers + 1};
+    }
+}
+
+static void mutateOperandNumberOfConsumersTest(const sp<IDevice>& device,
+                                               const V1_1::Model& model) {
+    for (size_t operand = 0; operand < model.operands.size(); ++operand) {
+        const std::vector<uint32_t> invalidNumberOfConsumersVec =
+                getInvalidNumberOfConsumers(model.operands[operand].numberOfConsumers);
+        for (uint32_t invalidNumberOfConsumers : invalidNumberOfConsumersVec) {
+            const std::string message =
+                    "mutateOperandNumberOfConsumersTest: operand " + std::to_string(operand) +
+                    " numberOfConsumers = " + std::to_string(invalidNumberOfConsumers);
+            validate(device, message, model,
+                     [operand, invalidNumberOfConsumers](Model* model, ExecutionPreference*) {
+                         model->operands[operand].numberOfConsumers = invalidNumberOfConsumers;
+                     });
+        }
+    }
+}
+
+///////////////////////// VALIDATE OPERAND NUMBER OF WRITERS ////////////////////////////////////
+
+static void mutateOperandAddWriterTest(const sp<IDevice>& device, const V1_1::Model& model) {
+    for (size_t operation = 0; operation < model.operations.size(); ++operation) {
+        for (size_t badOutputNum = 0; badOutputNum < model.operations[operation].outputs.size();
+             ++badOutputNum) {
+            const uint32_t outputOperandIndex = model.operations[operation].outputs[badOutputNum];
+            const std::string message = "mutateOperandAddWriterTest: operation " +
+                                        std::to_string(operation) + " writes to " +
+                                        std::to_string(outputOperandIndex);
+            // We'll insert a copy of the operation, all of whose
+            // OTHER output operands are newly-created -- i.e.,
+            // there'll only be a duplicate write of ONE of that
+            // operation's output operands.
+            validate(device, message, model,
+                     [operation, badOutputNum](Model* model, ExecutionPreference*) {
+                         Operation newOperation = model->operations[operation];
+                         for (uint32_t input : newOperation.inputs) {
+                             ++model->operands[input].numberOfConsumers;
+                         }
+                         for (size_t outputNum = 0; outputNum < newOperation.outputs.size();
+                              ++outputNum) {
+                             if (outputNum == badOutputNum) continue;
+
+                             Operand operandValue =
+                                     model->operands[newOperation.outputs[outputNum]];
+                             operandValue.numberOfConsumers = 0;
+                             if (operandValue.lifetime == OperandLifeTime::MODEL_OUTPUT) {
+                                 operandValue.lifetime = OperandLifeTime::TEMPORARY_VARIABLE;
+                             } else {
+                                 ASSERT_EQ(operandValue.lifetime,
+                                           OperandLifeTime::TEMPORARY_VARIABLE);
+                             }
+                             newOperation.outputs[outputNum] =
+                                     hidl_vec_push_back(&model->operands, operandValue);
+                         }
+                         // Where do we insert the extra writer (a new
+                         // operation)?  It has to be later than all the
+                         // writers of its inputs.  The easiest thing to do
+                         // is to insert it at the end of the operation
+                         // sequence.
+                         hidl_vec_push_back(&model->operations, newOperation);
+                     });
+        }
+    }
+}
+
 ///////////////////////// VALIDATE EXTRA ??? /////////////////////////
 
-// TODO: Operand::lifetime
 // TODO: Operand::location
 
 ///////////////////////// VALIDATE OPERATION OPERAND TYPE /////////////////////////
@@ -358,6 +801,37 @@
     }
 }
 
+///////////////////////// VALIDATE MODEL OPERANDS WRITTEN ///////////////////////////////////////
+
+static void mutateOperationRemoveWriteTest(const sp<IDevice>& device, const V1_1::Model& model) {
+    for (size_t operation = 0; operation < model.operations.size(); ++operation) {
+        for (size_t outputNum = 0; outputNum < model.operations[operation].outputs.size();
+             ++outputNum) {
+            const uint32_t outputOperandIndex = model.operations[operation].outputs[outputNum];
+            if (model.operands[outputOperandIndex].numberOfConsumers > 0) {
+                const std::string message = "mutateOperationRemoveWriteTest: operation " +
+                                            std::to_string(operation) + " writes to " +
+                                            std::to_string(outputOperandIndex);
+                validate(device, message, model,
+                         [operation, outputNum](Model* model, ExecutionPreference*) {
+                             uint32_t& outputOperandIndex =
+                                     model->operations[operation].outputs[outputNum];
+                             Operand operandValue = model->operands[outputOperandIndex];
+                             operandValue.numberOfConsumers = 0;
+                             if (operandValue.lifetime == OperandLifeTime::MODEL_OUTPUT) {
+                                 operandValue.lifetime = OperandLifeTime::TEMPORARY_VARIABLE;
+                             } else {
+                                 ASSERT_EQ(operandValue.lifetime,
+                                           OperandLifeTime::TEMPORARY_VARIABLE);
+                             }
+                             outputOperandIndex =
+                                     hidl_vec_push_back(&model->operands, operandValue);
+                         });
+            }
+        }
+    }
+}
+
 ///////////////////////// REMOVE OPERAND FROM EVERYTHING /////////////////////////
 
 static void removeValueAndDecrementGreaterValues(hidl_vec<uint32_t>* vec, uint32_t value) {
@@ -504,14 +978,20 @@
 ////////////////////////// ENTRY POINT //////////////////////////////
 
 void validateModel(const sp<IDevice>& device, const Model& model) {
+    mutateExecutionOrderTest(device, model);
     mutateOperandTypeTest(device, model);
     mutateOperandRankTest(device, model);
     mutateOperandScaleTest(device, model);
     mutateOperandZeroPointTest(device, model);
+    mutateOperandLifeTimeTest(device, model);
+    mutateOperandInputOutputTest(device, model);
+    mutateOperandNumberOfConsumersTest(device, model);
+    mutateOperandAddWriterTest(device, model);
     mutateOperationOperandTypeTest(device, model);
     mutateOperationTypeTest(device, model);
     mutateOperationInputOperandIndexTest(device, model);
     mutateOperationOutputOperandIndexTest(device, model);
+    mutateOperationRemoveWriteTest(device, model);
     removeOperandTest(device, model);
     removeOperationTest(device, model);
     removeOperationInputTest(device, model);
diff --git a/neuralnetworks/1.2/vts/functional/Android.bp b/neuralnetworks/1.2/vts/functional/Android.bp
index 481eb80..182f716 100644
--- a/neuralnetworks/1.2/vts/functional/Android.bp
+++ b/neuralnetworks/1.2/vts/functional/Android.bp
@@ -15,11 +15,12 @@
 //
 
 cc_library_static {
-    name: "VtsHalNeuralNetworksV1_2Callbacks",
+    name: "VtsHalNeuralNetworksV1_2_utils",
     defaults: ["neuralnetworks_vts_functional_defaults"],
     export_include_dirs: ["include"],
     srcs: [
         "Callbacks.cpp",
+        "Utils.cpp",
     ],
     static_libs: [
         "android.hardware.neuralnetworks@1.0",
@@ -51,7 +52,7 @@
     ],
     static_libs: [
         "VtsHalNeuralNetworksV1_0_utils",
-        "VtsHalNeuralNetworksV1_2Callbacks",
+        "VtsHalNeuralNetworksV1_2_utils",
         "android.hardware.neuralnetworks@1.0",
         "android.hardware.neuralnetworks@1.1",
         "android.hardware.neuralnetworks@1.2",
diff --git a/neuralnetworks/1.2/vts/functional/BasicTests.cpp b/neuralnetworks/1.2/vts/functional/BasicTests.cpp
index 58d3c4a..77340e7 100644
--- a/neuralnetworks/1.2/vts/functional/BasicTests.cpp
+++ b/neuralnetworks/1.2/vts/functional/BasicTests.cpp
@@ -20,9 +20,13 @@
 
 namespace android::hardware::neuralnetworks::V1_2::vts::functional {
 
+using implementation::PreparedModelCallback;
 using V1_0::DeviceStatus;
 using V1_0::ErrorStatus;
+using V1_0::OperandLifeTime;
 using V1_0::PerformanceInfo;
+using V1_1::ExecutionPreference;
+using HidlToken = hidl_array<uint8_t, static_cast<uint32_t>(Constant::BYTE_SIZE_OF_CACHE_TOKEN)>;
 
 // create device test
 TEST_P(NeuralnetworksHidlTest, CreateDevice) {}
@@ -123,4 +127,139 @@
             });
     EXPECT_TRUE(ret.isOk());
 }
+
+// detect cycle
+TEST_P(NeuralnetworksHidlTest, CycleTest) {
+    // opnd0 = TENSOR_FLOAT32            // model input
+    // opnd1 = TENSOR_FLOAT32            // model input
+    // opnd2 = INT32                     // model input
+    // opnd3 = ADD(opnd0, opnd4, opnd2)
+    // opnd4 = ADD(opnd1, opnd3, opnd2)
+    // opnd5 = ADD(opnd4, opnd0, opnd2)  // model output
+    //
+    //            +-----+
+    //            |     |
+    //            v     |
+    // 3 = ADD(0, 4, 2) |
+    // |                |
+    // +----------+     |
+    //            |     |
+    //            v     |
+    // 4 = ADD(1, 3, 2) |
+    // |                |
+    // +----------------+
+    // |
+    // |
+    // +-------+
+    //         |
+    //         v
+    // 5 = ADD(4, 0, 2)
+
+    const std::vector<Operand> operands = {
+            {
+                    // operands[0]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 2,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::MODEL_INPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[1]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 1,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::MODEL_INPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[2]
+                    .type = OperandType::INT32,
+                    .dimensions = {},
+                    .numberOfConsumers = 3,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::MODEL_INPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[3]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 1,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::TEMPORARY_VARIABLE,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[4]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 2,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::TEMPORARY_VARIABLE,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[5]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 0,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::MODEL_OUTPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+    };
+
+    const std::vector<Operation> operations = {
+            {.type = OperationType::ADD, .inputs = {0, 4, 2}, .outputs = {3}},
+            {.type = OperationType::ADD, .inputs = {1, 3, 2}, .outputs = {4}},
+            {.type = OperationType::ADD, .inputs = {4, 0, 2}, .outputs = {5}},
+    };
+
+    const Model model = {
+            .operands = operands,
+            .operations = operations,
+            .inputIndexes = {0, 1, 2},
+            .outputIndexes = {5},
+            .operandValues = {},
+            .pools = {},
+    };
+
+    // ensure that getSupportedOperations_1_2() checks model validity
+    ErrorStatus supportedOpsErrorStatus = ErrorStatus::GENERAL_FAILURE;
+    Return<void> supportedOpsReturn = kDevice->getSupportedOperations_1_2(
+            model, [&model, &supportedOpsErrorStatus](ErrorStatus status,
+                                                      const hidl_vec<bool>& supported) {
+                supportedOpsErrorStatus = status;
+                if (status == ErrorStatus::NONE) {
+                    ASSERT_EQ(supported.size(), model.operations.size());
+                }
+            });
+    ASSERT_TRUE(supportedOpsReturn.isOk());
+    ASSERT_EQ(supportedOpsErrorStatus, ErrorStatus::INVALID_ARGUMENT);
+
+    // ensure that prepareModel_1_2() checks model validity
+    sp<PreparedModelCallback> preparedModelCallback = new PreparedModelCallback;
+    Return<ErrorStatus> prepareLaunchReturn = kDevice->prepareModel_1_2(
+            model, ExecutionPreference::FAST_SINGLE_ANSWER, hidl_vec<hidl_handle>(),
+            hidl_vec<hidl_handle>(), HidlToken(), preparedModelCallback);
+    ASSERT_TRUE(prepareLaunchReturn.isOk());
+    //     Note that preparation can fail for reasons other than an
+    //     invalid model (invalid model should result in
+    //     INVALID_ARGUMENT) -- for example, perhaps not all
+    //     operations are supported, or perhaps the device hit some
+    //     kind of capacity limit.
+    EXPECT_NE(prepareLaunchReturn, ErrorStatus::NONE);
+    EXPECT_NE(preparedModelCallback->getStatus(), ErrorStatus::NONE);
+    EXPECT_EQ(preparedModelCallback->getPreparedModel(), nullptr);
+}
+
 }  // namespace android::hardware::neuralnetworks::V1_2::vts::functional
diff --git a/neuralnetworks/1.2/vts/functional/Utils.cpp b/neuralnetworks/1.2/vts/functional/Utils.cpp
new file mode 100644
index 0000000..cc654f2
--- /dev/null
+++ b/neuralnetworks/1.2/vts/functional/Utils.cpp
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+
+#include <android-base/logging.h>
+#include <android/hardware/neuralnetworks/1.2/types.h>
+
+#include <functional>
+#include <numeric>
+
+namespace android {
+namespace hardware {
+namespace neuralnetworks {
+
+uint32_t sizeOfData(V1_2::OperandType type) {
+    switch (type) {
+        case V1_2::OperandType::FLOAT32:
+        case V1_2::OperandType::INT32:
+        case V1_2::OperandType::UINT32:
+        case V1_2::OperandType::TENSOR_FLOAT32:
+        case V1_2::OperandType::TENSOR_INT32:
+            return 4;
+        case V1_2::OperandType::TENSOR_QUANT16_SYMM:
+        case V1_2::OperandType::TENSOR_FLOAT16:
+        case V1_2::OperandType::FLOAT16:
+        case V1_2::OperandType::TENSOR_QUANT16_ASYMM:
+            return 2;
+        case V1_2::OperandType::TENSOR_QUANT8_ASYMM:
+        case V1_2::OperandType::BOOL:
+        case V1_2::OperandType::TENSOR_BOOL8:
+        case V1_2::OperandType::TENSOR_QUANT8_SYMM_PER_CHANNEL:
+        case V1_2::OperandType::TENSOR_QUANT8_SYMM:
+            return 1;
+        default:
+            CHECK(false) << "Invalid OperandType " << static_cast<uint32_t>(type);
+            return 0;
+    }
+}
+
+static bool isTensor(V1_2::OperandType type) {
+    switch (type) {
+        case V1_2::OperandType::FLOAT32:
+        case V1_2::OperandType::INT32:
+        case V1_2::OperandType::UINT32:
+        case V1_2::OperandType::FLOAT16:
+        case V1_2::OperandType::BOOL:
+            return false;
+        case V1_2::OperandType::TENSOR_FLOAT32:
+        case V1_2::OperandType::TENSOR_INT32:
+        case V1_2::OperandType::TENSOR_QUANT16_SYMM:
+        case V1_2::OperandType::TENSOR_FLOAT16:
+        case V1_2::OperandType::TENSOR_QUANT16_ASYMM:
+        case V1_2::OperandType::TENSOR_QUANT8_ASYMM:
+        case V1_2::OperandType::TENSOR_BOOL8:
+        case V1_2::OperandType::TENSOR_QUANT8_SYMM_PER_CHANNEL:
+        case V1_2::OperandType::TENSOR_QUANT8_SYMM:
+            return true;
+        default:
+            CHECK(false) << "Invalid OperandType " << static_cast<uint32_t>(type);
+            return false;
+    }
+}
+
+uint32_t sizeOfData(const V1_2::Operand& operand) {
+    const uint32_t dataSize = sizeOfData(operand.type);
+    if (isTensor(operand.type) && operand.dimensions.size() == 0) return 0;
+    return std::accumulate(operand.dimensions.begin(), operand.dimensions.end(), dataSize,
+                           std::multiplies<>{});
+}
+
+}  // namespace neuralnetworks
+}  // namespace hardware
+}  // namespace android
diff --git a/neuralnetworks/1.2/vts/functional/ValidateModel.cpp b/neuralnetworks/1.2/vts/functional/ValidateModel.cpp
index e9fc6e9..6583dfe 100644
--- a/neuralnetworks/1.2/vts/functional/ValidateModel.cpp
+++ b/neuralnetworks/1.2/vts/functional/ValidateModel.cpp
@@ -16,14 +16,21 @@
 
 #define LOG_TAG "neuralnetworks_hidl_hal_test"
 
+#include <android/hardware/neuralnetworks/1.1/types.h>
 #include "1.0/Utils.h"
 #include "1.2/Callbacks.h"
+#include "1.2/Utils.h"
 #include "GeneratedTestHarness.h"
 #include "VtsHalNeuralnetworks.h"
 
+#include <optional>
+#include <type_traits>
+#include <utility>
+
 namespace android::hardware::neuralnetworks::V1_2::vts::functional {
 
 using implementation::PreparedModelCallback;
+using V1_0::DataLocation;
 using V1_0::ErrorStatus;
 using V1_0::OperandLifeTime;
 using V1_1::ExecutionPreference;
@@ -105,6 +112,250 @@
     return index;
 }
 
+// If we introduce a CONSTANT_COPY for an operand of size operandSize,
+// how much will this increase the size of the model?  This assumes
+// that we can (re)use all of model.operandValues for the operand
+// value.
+static size_t constantCopyExtraSize(const Model& model, size_t operandSize) {
+    const size_t operandValuesSize = model.operandValues.size();
+    return (operandValuesSize < operandSize) ? (operandSize - operandValuesSize) : 0;
+}
+
+// Highly specialized utility routine for converting an operand to
+// CONSTANT_COPY lifetime.
+//
+// Expects that:
+// - operand has a known size
+// - operand->lifetime has already been set to CONSTANT_COPY
+// - operand->location has been zeroed out
+//
+// Does the following:
+// - initializes operand->location to point to the beginning of model->operandValues
+// - resizes model->operandValues (if necessary) to be large enough for the operand
+//   value, padding it with zeroes on the end
+//
+// Potential problem:
+// By changing the operand to CONSTANT_COPY lifetime, this function is effectively initializing the
+// operand with unspecified (but deterministic) data. This means that the model may be invalidated
+// in two ways: not only is the lifetime of CONSTANT_COPY invalid, but the operand's value in the
+// graph may also be invalid (e.g., if the operand is used as an activation code and has an invalid
+// value). For now, this should be fine because it just means we're not testing what we think we're
+// testing in certain cases; but we can handwave this and assume we're probabilistically likely to
+// exercise the validation code over the span of the entire test set and operand space.
+//
+// Aborts if the specified operand type is an extension type or OEM type.
+static void becomeConstantCopy(Model* model, Operand* operand) {
+    // sizeOfData will abort if the specified type is an extension type or OEM type.
+    const size_t sizeOfOperand = sizeOfData(*operand);
+    EXPECT_NE(sizeOfOperand, size_t(0));
+    operand->location.poolIndex = 0;
+    operand->location.offset = 0;
+    operand->location.length = sizeOfOperand;
+    if (model->operandValues.size() < sizeOfOperand) {
+        model->operandValues.resize(sizeOfOperand);
+    }
+}
+
+// The sizeForBinder() functions estimate the size of the
+// representation of a value when sent to binder.  It's probably a bit
+// of an under-estimate, because we don't know the size of the
+// metadata in the binder format (e.g., representation of the size of
+// a vector); but at least it adds up "big" things like vector
+// contents.  However, it doesn't treat inter-field or end-of-struct
+// padding in a methodical way -- there's no attempt to be consistent
+// in whether or not padding in the native (C++) representation
+// contributes to the estimated size for the binder representation;
+// and there's no attempt to understand what padding (if any) is
+// needed in the binder representation.
+//
+// This assumes that non-metadata uses a fixed length encoding (e.g.,
+// a uint32_t is always encoded in sizeof(uint32_t) bytes, rather than
+// using an encoding whose length is related to the magnitude of the
+// encoded value).
+
+template <typename Type>
+static size_t sizeForBinder(const Type& val) {
+    static_assert(std::is_trivially_copyable_v<std::remove_reference_t<Type>>,
+                  "expected a trivially copyable type");
+    return sizeof(val);
+}
+
+template <typename Type>
+static size_t sizeForBinder(const hidl_vec<Type>& vec) {
+    return std::accumulate(vec.begin(), vec.end(), 0,
+                           [](size_t acc, const Type& x) { return acc + sizeForBinder(x); });
+}
+
+template <>
+size_t sizeForBinder(const SymmPerChannelQuantParams& symmPerChannelQuantParams) {
+    size_t size = 0;
+
+    size += sizeForBinder(symmPerChannelQuantParams.scales);
+    size += sizeForBinder(symmPerChannelQuantParams.channelDim);
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const Operand::ExtraParams& extraParams) {
+    using Discriminator = Operand::ExtraParams::hidl_discriminator;
+    switch (extraParams.getDiscriminator()) {
+        case Discriminator::none:
+            return 0;
+        case Discriminator::channelQuant:
+            return sizeForBinder(extraParams.channelQuant());
+        case Discriminator::extension:
+            return sizeForBinder(extraParams.extension());
+    }
+    LOG(FATAL) << "Unrecognized extraParams enum: "
+               << static_cast<int>(extraParams.getDiscriminator());
+    return 0;
+}
+
+template <>
+size_t sizeForBinder(const Operand& operand) {
+    size_t size = 0;
+
+    size += sizeForBinder(operand.type);
+    size += sizeForBinder(operand.dimensions);
+    size += sizeForBinder(operand.numberOfConsumers);
+    size += sizeForBinder(operand.scale);
+    size += sizeForBinder(operand.zeroPoint);
+    size += sizeForBinder(operand.lifetime);
+    size += sizeForBinder(operand.location);
+    size += sizeForBinder(operand.extraParams);
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const Operation& operation) {
+    size_t size = 0;
+
+    size += sizeForBinder(operation.type);
+    size += sizeForBinder(operation.inputs);
+    size += sizeForBinder(operation.outputs);
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const hidl_string& name) {
+    return name.size();
+}
+
+template <>
+size_t sizeForBinder(const hidl_memory& memory) {
+    // This is just a guess.
+
+    size_t size = 0;
+
+    if (const native_handle_t* handle = memory.handle()) {
+        size += sizeof(*handle);
+        size += sizeof(handle->data[0] * (handle->numFds + handle->numInts));
+    }
+    size += sizeForBinder(memory.name());
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const Model::ExtensionNameAndPrefix& extensionNameToPrefix) {
+    size_t size = 0;
+
+    size += sizeForBinder(extensionNameToPrefix.name);
+    size += sizeForBinder(extensionNameToPrefix.prefix);
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const Model& model) {
+    size_t size = 0;
+
+    size += sizeForBinder(model.operands);
+    size += sizeForBinder(model.operations);
+    size += sizeForBinder(model.inputIndexes);
+    size += sizeForBinder(model.outputIndexes);
+    size += sizeForBinder(model.operandValues);
+    size += sizeForBinder(model.pools);
+    size += sizeForBinder(model.relaxComputationFloat32toFloat16);
+    size += sizeForBinder(model.extensionNameToPrefix);
+
+    return size;
+}
+
+// https://developer.android.com/reference/android/os/TransactionTooLargeException.html
+//
+//     "The Binder transaction buffer has a limited fixed size,
+//     currently 1Mb, which is shared by all transactions in progress
+//     for the process."
+//
+// Will our representation fit under this limit?  There are two complications:
+// - Our representation size is just approximate (see sizeForBinder()).
+// - This object may not be the only occupant of the Binder transaction buffer.
+// So we'll be very conservative: We want the representation size to be no
+// larger than half the transaction buffer size.
+//
+// If our representation grows large enough that it still fits within
+// the transaction buffer but combined with other transactions may
+// exceed the buffer size, then we may see intermittent HAL transport
+// errors.
+static bool exceedsBinderSizeLimit(size_t representationSize) {
+    // Instead of using this fixed buffer size, we might instead be able to use
+    // ProcessState::self()->getMmapSize(). However, this has a potential
+    // problem: The binder/mmap size of the current process does not necessarily
+    // indicate the binder/mmap size of the service (i.e., the other process).
+    // The only way it would be a good indication is if both the current process
+    // and the service use the default size.
+    static const size_t kHalfBufferSize = 1024 * 1024 / 2;
+
+    return representationSize > kHalfBufferSize;
+}
+
+///////////////////////// VALIDATE EXECUTION ORDER ////////////////////////////
+
+static void mutateExecutionOrderTest(const sp<IDevice>& device, const Model& model) {
+    for (size_t operation = 0; operation < model.operations.size(); ++operation) {
+        const Operation& operationObj = model.operations[operation];
+        for (uint32_t input : operationObj.inputs) {
+            if (model.operands[input].lifetime == OperandLifeTime::TEMPORARY_VARIABLE ||
+                model.operands[input].lifetime == OperandLifeTime::MODEL_OUTPUT) {
+                // This operation reads an operand written by some
+                // other operation.  Move this operation to the
+                // beginning of the sequence, ensuring that it reads
+                // the operand before that operand is written, thereby
+                // violating execution order rules.
+                const std::string message = "mutateExecutionOrderTest: operation " +
+                                            std::to_string(operation) + " is a reader";
+                validate(device, message, model, [operation](Model* model, ExecutionPreference*) {
+                    auto& operations = model->operations;
+                    std::rotate(operations.begin(), operations.begin() + operation,
+                                operations.begin() + operation + 1);
+                });
+                break;  // only need to do this once per operation
+            }
+        }
+        for (uint32_t output : operationObj.outputs) {
+            if (model.operands[output].numberOfConsumers > 0) {
+                // This operation writes an operand read by some other
+                // operation.  Move this operation to the end of the
+                // sequence, ensuring that it writes the operand after
+                // that operand is read, thereby violating execution
+                // order rules.
+                const std::string message = "mutateExecutionOrderTest: operation " +
+                                            std::to_string(operation) + " is a writer";
+                validate(device, message, model, [operation](Model* model, ExecutionPreference*) {
+                    auto& operations = model->operations;
+                    std::rotate(operations.begin() + operation, operations.begin() + operation + 1,
+                                operations.end());
+                });
+                break;  // only need to do this once per operation
+            }
+        }
+    }
+}
+
 ///////////////////////// VALIDATE MODEL OPERAND TYPE /////////////////////////
 
 static const uint32_t invalidOperandTypes[] = {
@@ -251,9 +502,239 @@
     }
 }
 
+///////////////////////// VALIDATE OPERAND LIFETIME /////////////////////////////////////////////
+
+static std::vector<OperandLifeTime> getInvalidLifeTimes(const Model& model, size_t modelSize,
+                                                        const Operand& operand) {
+    // TODO: Support OperandLifeTime::CONSTANT_REFERENCE as an invalid lifetime
+    // TODO: Support OperandLifeTime::NO_VALUE as an invalid lifetime
+
+    // Ways to get an invalid lifetime:
+    // - change whether a lifetime means an operand should have a writer
+    std::vector<OperandLifeTime> ret;
+    switch (operand.lifetime) {
+        case OperandLifeTime::MODEL_OUTPUT:
+        case OperandLifeTime::TEMPORARY_VARIABLE:
+            ret = {
+                    OperandLifeTime::MODEL_INPUT,
+                    OperandLifeTime::CONSTANT_COPY,
+            };
+            break;
+        case OperandLifeTime::CONSTANT_COPY:
+        case OperandLifeTime::CONSTANT_REFERENCE:
+        case OperandLifeTime::MODEL_INPUT:
+            ret = {
+                    OperandLifeTime::TEMPORARY_VARIABLE,
+                    OperandLifeTime::MODEL_OUTPUT,
+            };
+            break;
+        case OperandLifeTime::NO_VALUE:
+            // Not enough information to know whether
+            // TEMPORARY_VARIABLE or CONSTANT_COPY would be invalid --
+            // is this operand written (then CONSTANT_COPY would be
+            // invalid) or not (then TEMPORARY_VARIABLE would be
+            // invalid)?
+            break;
+        default:
+            ADD_FAILURE();
+            break;
+    }
+
+    const size_t operandSize = sizeOfData(operand);  // will be zero if shape is unknown
+    if (!operandSize ||
+        exceedsBinderSizeLimit(modelSize + constantCopyExtraSize(model, operandSize))) {
+        // Unknown size or too-large size
+        ret.erase(std::remove(ret.begin(), ret.end(), OperandLifeTime::CONSTANT_COPY), ret.end());
+    }
+
+    return ret;
+}
+
+static void mutateOperandLifeTimeTest(const sp<IDevice>& device, const Model& model) {
+    const size_t modelSize = sizeForBinder(model);
+    for (size_t operand = 0; operand < model.operands.size(); ++operand) {
+        const std::vector<OperandLifeTime> invalidLifeTimes =
+                getInvalidLifeTimes(model, modelSize, model.operands[operand]);
+        for (OperandLifeTime invalidLifeTime : invalidLifeTimes) {
+            const std::string message = "mutateOperandLifetimeTest: operand " +
+                                        std::to_string(operand) + " has lifetime " +
+                                        toString(invalidLifeTime) + " instead of lifetime " +
+                                        toString(model.operands[operand].lifetime);
+            validate(device, message, model,
+                     [operand, invalidLifeTime](Model* model, ExecutionPreference*) {
+                         static const DataLocation kZeroDataLocation = {};
+                         Operand& operandObj = model->operands[operand];
+                         switch (operandObj.lifetime) {
+                             case OperandLifeTime::MODEL_INPUT: {
+                                 hidl_vec_remove(&model->inputIndexes, uint32_t(operand));
+                                 break;
+                             }
+                             case OperandLifeTime::MODEL_OUTPUT: {
+                                 hidl_vec_remove(&model->outputIndexes, uint32_t(operand));
+                                 break;
+                             }
+                             default:
+                                 break;
+                         }
+                         operandObj.lifetime = invalidLifeTime;
+                         operandObj.location = kZeroDataLocation;
+                         switch (invalidLifeTime) {
+                             case OperandLifeTime::CONSTANT_COPY: {
+                                 becomeConstantCopy(model, &operandObj);
+                                 break;
+                             }
+                             case OperandLifeTime::MODEL_INPUT:
+                                 hidl_vec_push_back(&model->inputIndexes, uint32_t(operand));
+                                 break;
+                             case OperandLifeTime::MODEL_OUTPUT:
+                                 hidl_vec_push_back(&model->outputIndexes, uint32_t(operand));
+                                 break;
+                             default:
+                                 break;
+                         }
+                     });
+        }
+    }
+}
+
+///////////////////////// VALIDATE OPERAND INPUT-or-OUTPUT //////////////////////////////////////
+
+static std::optional<OperandLifeTime> getInputOutputLifeTime(const Model& model, size_t modelSize,
+                                                             const Operand& operand) {
+    // Ways to get an invalid lifetime (with respect to model inputIndexes and outputIndexes):
+    // - change whether a lifetime means an operand is a model input, a model output, or neither
+    // - preserve whether or not a lifetime means an operand should have a writer
+    switch (operand.lifetime) {
+        case OperandLifeTime::CONSTANT_COPY:
+        case OperandLifeTime::CONSTANT_REFERENCE:
+            return OperandLifeTime::MODEL_INPUT;
+        case OperandLifeTime::MODEL_INPUT: {
+            const size_t operandSize = sizeOfData(operand);  // will be zero if shape is unknown
+            if (!operandSize ||
+                exceedsBinderSizeLimit(modelSize + constantCopyExtraSize(model, operandSize))) {
+                // Unknown size or too-large size
+                break;
+            }
+            return OperandLifeTime::CONSTANT_COPY;
+        }
+        case OperandLifeTime::MODEL_OUTPUT:
+            return OperandLifeTime::TEMPORARY_VARIABLE;
+        case OperandLifeTime::TEMPORARY_VARIABLE:
+            return OperandLifeTime::MODEL_OUTPUT;
+        case OperandLifeTime::NO_VALUE:
+            // Not enough information to know whether
+            // TEMPORARY_VARIABLE or CONSTANT_COPY would be an
+            // appropriate choice -- is this operand written (then
+            // TEMPORARY_VARIABLE would be appropriate) or not (then
+            // CONSTANT_COPY would be appropriate)?
+            break;
+        default:
+            ADD_FAILURE();
+            break;
+    }
+
+    return std::nullopt;
+}
+
+static void mutateOperandInputOutputTest(const sp<IDevice>& device, const Model& model) {
+    const size_t modelSize = sizeForBinder(model);
+    for (size_t operand = 0; operand < model.operands.size(); ++operand) {
+        const std::optional<OperandLifeTime> changedLifeTime =
+                getInputOutputLifeTime(model, modelSize, model.operands[operand]);
+        if (changedLifeTime) {
+            const std::string message = "mutateOperandInputOutputTest: operand " +
+                                        std::to_string(operand) + " has lifetime " +
+                                        toString(*changedLifeTime) + " instead of lifetime " +
+                                        toString(model.operands[operand].lifetime);
+            validate(device, message, model,
+                     [operand, changedLifeTime](Model* model, ExecutionPreference*) {
+                         static const DataLocation kZeroDataLocation = {};
+                         Operand& operandObj = model->operands[operand];
+                         operandObj.lifetime = *changedLifeTime;
+                         operandObj.location = kZeroDataLocation;
+                         if (*changedLifeTime == OperandLifeTime::CONSTANT_COPY) {
+                             becomeConstantCopy(model, &operandObj);
+                         }
+                     });
+        }
+    }
+}
+
+///////////////////////// VALIDATE OPERAND NUMBER OF CONSUMERS //////////////////////////////////
+
+static std::vector<uint32_t> getInvalidNumberOfConsumers(uint32_t numberOfConsumers) {
+    if (numberOfConsumers == 0) {
+        return {1};
+    } else {
+        return {numberOfConsumers - 1, numberOfConsumers + 1};
+    }
+}
+
+static void mutateOperandNumberOfConsumersTest(const sp<IDevice>& device, const Model& model) {
+    for (size_t operand = 0; operand < model.operands.size(); ++operand) {
+        const std::vector<uint32_t> invalidNumberOfConsumersVec =
+                getInvalidNumberOfConsumers(model.operands[operand].numberOfConsumers);
+        for (uint32_t invalidNumberOfConsumers : invalidNumberOfConsumersVec) {
+            const std::string message =
+                    "mutateOperandNumberOfConsumersTest: operand " + std::to_string(operand) +
+                    " numberOfConsumers = " + std::to_string(invalidNumberOfConsumers);
+            validate(device, message, model,
+                     [operand, invalidNumberOfConsumers](Model* model, ExecutionPreference*) {
+                         model->operands[operand].numberOfConsumers = invalidNumberOfConsumers;
+                     });
+        }
+    }
+}
+
+///////////////////////// VALIDATE OPERAND NUMBER OF WRITERS ////////////////////////////////////
+
+static void mutateOperandAddWriterTest(const sp<IDevice>& device, const Model& model) {
+    for (size_t operation = 0; operation < model.operations.size(); ++operation) {
+        for (size_t badOutputNum = 0; badOutputNum < model.operations[operation].outputs.size();
+             ++badOutputNum) {
+            const uint32_t outputOperandIndex = model.operations[operation].outputs[badOutputNum];
+            const std::string message = "mutateOperandAddWriterTest: operation " +
+                                        std::to_string(operation) + " writes to " +
+                                        std::to_string(outputOperandIndex);
+            // We'll insert a copy of the operation, all of whose
+            // OTHER output operands are newly-created -- i.e.,
+            // there'll only be a duplicate write of ONE of that
+            // operation's output operands.
+            validate(device, message, model,
+                     [operation, badOutputNum](Model* model, ExecutionPreference*) {
+                         Operation newOperation = model->operations[operation];
+                         for (uint32_t input : newOperation.inputs) {
+                             ++model->operands[input].numberOfConsumers;
+                         }
+                         for (size_t outputNum = 0; outputNum < newOperation.outputs.size();
+                              ++outputNum) {
+                             if (outputNum == badOutputNum) continue;
+
+                             Operand operandValue =
+                                     model->operands[newOperation.outputs[outputNum]];
+                             operandValue.numberOfConsumers = 0;
+                             if (operandValue.lifetime == OperandLifeTime::MODEL_OUTPUT) {
+                                 operandValue.lifetime = OperandLifeTime::TEMPORARY_VARIABLE;
+                             } else {
+                                 ASSERT_EQ(operandValue.lifetime,
+                                           OperandLifeTime::TEMPORARY_VARIABLE);
+                             }
+                             newOperation.outputs[outputNum] =
+                                     hidl_vec_push_back(&model->operands, operandValue);
+                         }
+                         // Where do we insert the extra writer (a new
+                         // operation)?  It has to be later than all the
+                         // writers of its inputs.  The easiest thing to do
+                         // is to insert it at the end of the operation
+                         // sequence.
+                         hidl_vec_push_back(&model->operations, newOperation);
+                     });
+        }
+    }
+}
+
 ///////////////////////// VALIDATE EXTRA ??? /////////////////////////
 
-// TODO: Operand::lifetime
 // TODO: Operand::location
 
 ///////////////////////// VALIDATE OPERATION OPERAND TYPE /////////////////////////
@@ -461,6 +942,37 @@
     }
 }
 
+///////////////////////// VALIDATE MODEL OPERANDS WRITTEN ///////////////////////////////////////
+
+static void mutateOperationRemoveWriteTest(const sp<IDevice>& device, const Model& model) {
+    for (size_t operation = 0; operation < model.operations.size(); ++operation) {
+        for (size_t outputNum = 0; outputNum < model.operations[operation].outputs.size();
+             ++outputNum) {
+            const uint32_t outputOperandIndex = model.operations[operation].outputs[outputNum];
+            if (model.operands[outputOperandIndex].numberOfConsumers > 0) {
+                const std::string message = "mutateOperationRemoveWriteTest: operation " +
+                                            std::to_string(operation) + " writes to " +
+                                            std::to_string(outputOperandIndex);
+                validate(device, message, model,
+                         [operation, outputNum](Model* model, ExecutionPreference*) {
+                             uint32_t& outputOperandIndex =
+                                     model->operations[operation].outputs[outputNum];
+                             Operand operandValue = model->operands[outputOperandIndex];
+                             operandValue.numberOfConsumers = 0;
+                             if (operandValue.lifetime == OperandLifeTime::MODEL_OUTPUT) {
+                                 operandValue.lifetime = OperandLifeTime::TEMPORARY_VARIABLE;
+                             } else {
+                                 ASSERT_EQ(operandValue.lifetime,
+                                           OperandLifeTime::TEMPORARY_VARIABLE);
+                             }
+                             outputOperandIndex =
+                                     hidl_vec_push_back(&model->operands, operandValue);
+                         });
+            }
+        }
+    }
+}
+
 ///////////////////////// REMOVE OPERAND FROM EVERYTHING /////////////////////////
 
 static void removeValueAndDecrementGreaterValues(hidl_vec<uint32_t>* vec, uint32_t value) {
@@ -711,14 +1223,20 @@
 ////////////////////////// ENTRY POINT //////////////////////////////
 
 void validateModel(const sp<IDevice>& device, const Model& model) {
+    mutateExecutionOrderTest(device, model);
     mutateOperandTypeTest(device, model);
     mutateOperandRankTest(device, model);
     mutateOperandScaleTest(device, model);
     mutateOperandZeroPointTest(device, model);
+    mutateOperandLifeTimeTest(device, model);
+    mutateOperandInputOutputTest(device, model);
+    mutateOperandNumberOfConsumersTest(device, model);
+    mutateOperandAddWriterTest(device, model);
     mutateOperationOperandTypeTest(device, model);
     mutateOperationTypeTest(device, model);
     mutateOperationInputOperandIndexTest(device, model);
     mutateOperationOutputOperandIndexTest(device, model);
+    mutateOperationRemoveWriteTest(device, model);
     removeOperandTest(device, model);
     removeOperationTest(device, model);
     removeOperationInputTest(device, model);
diff --git a/neuralnetworks/1.2/vts/functional/include/1.2/Utils.h b/neuralnetworks/1.2/vts/functional/include/1.2/Utils.h
new file mode 100644
index 0000000..61a8d74
--- /dev/null
+++ b/neuralnetworks/1.2/vts/functional/include/1.2/Utils.h
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+
+#ifndef ANDROID_HARDWARE_NEURALNETWORKS_V1_2_UTILS_H
+#define ANDROID_HARDWARE_NEURALNETWORKS_V1_2_UTILS_H
+
+#include <android/hardware/neuralnetworks/1.2/types.h>
+
+namespace android {
+namespace hardware {
+namespace neuralnetworks {
+
+// Returns the amount of space needed to store a value of the specified type.
+//
+// Aborts if the specified type is an extension type or OEM type.
+uint32_t sizeOfData(V1_2::OperandType type);
+
+// Returns the amount of space needed to store a value of the dimensions and
+// type of this operand. For a non-extension, non-OEM tensor with unspecified
+// rank or at least one unspecified dimension, returns zero.
+//
+// Aborts if the specified type is an extension type or OEM type.
+uint32_t sizeOfData(const V1_2::Operand& operand);
+
+}  // namespace neuralnetworks
+}  // namespace hardware
+}  // namespace android
+
+#endif  // ANDROID_HARDWARE_NEURALNETWORKS_V1_2_UTILS_H
diff --git a/neuralnetworks/1.3/vts/functional/Android.bp b/neuralnetworks/1.3/vts/functional/Android.bp
index 545a5be..457e36e 100644
--- a/neuralnetworks/1.3/vts/functional/Android.bp
+++ b/neuralnetworks/1.3/vts/functional/Android.bp
@@ -54,7 +54,7 @@
     ],
     static_libs: [
         "VtsHalNeuralNetworksV1_0_utils",
-        "VtsHalNeuralNetworksV1_2Callbacks",
+        "VtsHalNeuralNetworksV1_2_utils",
         "VtsHalNeuralNetworksV1_3_utils",
         "android.hardware.neuralnetworks@1.0",
         "android.hardware.neuralnetworks@1.1",
diff --git a/neuralnetworks/1.3/vts/functional/BasicTests.cpp b/neuralnetworks/1.3/vts/functional/BasicTests.cpp
index 1c25369..6fcfc34 100644
--- a/neuralnetworks/1.3/vts/functional/BasicTests.cpp
+++ b/neuralnetworks/1.3/vts/functional/BasicTests.cpp
@@ -20,11 +20,14 @@
 
 namespace android::hardware::neuralnetworks::V1_3::vts::functional {
 
+using implementation::PreparedModelCallback;
 using V1_0::DeviceStatus;
 using V1_0::PerformanceInfo;
+using V1_1::ExecutionPreference;
 using V1_2::Constant;
 using V1_2::DeviceType;
 using V1_2::Extension;
+using HidlToken = hidl_array<uint8_t, static_cast<uint32_t>(Constant::BYTE_SIZE_OF_CACHE_TOKEN)>;
 
 // create device test
 TEST_P(NeuralnetworksHidlTest, CreateDevice) {}
@@ -65,4 +68,143 @@
     });
     EXPECT_TRUE(ret.isOk());
 }
+
+// detect cycle
+TEST_P(NeuralnetworksHidlTest, CycleTest) {
+    // opnd0 = TENSOR_FLOAT32            // model input
+    // opnd1 = TENSOR_FLOAT32            // model input
+    // opnd2 = INT32                     // model input
+    // opnd3 = ADD(opnd0, opnd4, opnd2)
+    // opnd4 = ADD(opnd1, opnd3, opnd2)
+    // opnd5 = ADD(opnd4, opnd0, opnd2)  // model output
+    //
+    //            +-----+
+    //            |     |
+    //            v     |
+    // 3 = ADD(0, 4, 2) |
+    // |                |
+    // +----------+     |
+    //            |     |
+    //            v     |
+    // 4 = ADD(1, 3, 2) |
+    // |                |
+    // +----------------+
+    // |
+    // |
+    // +-------+
+    //         |
+    //         v
+    // 5 = ADD(4, 0, 2)
+
+    const std::vector<Operand> operands = {
+            {
+                    // operands[0]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 2,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::SUBGRAPH_INPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[1]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 1,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::SUBGRAPH_INPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[2]
+                    .type = OperandType::INT32,
+                    .dimensions = {},
+                    .numberOfConsumers = 3,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::SUBGRAPH_INPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[3]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 1,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::TEMPORARY_VARIABLE,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[4]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 2,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::TEMPORARY_VARIABLE,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+            {
+                    // operands[5]
+                    .type = OperandType::TENSOR_FLOAT32,
+                    .dimensions = {1},
+                    .numberOfConsumers = 0,
+                    .scale = 0.0f,
+                    .zeroPoint = 0,
+                    .lifetime = OperandLifeTime::SUBGRAPH_OUTPUT,
+                    .location = {.poolIndex = 0, .offset = 0, .length = 0},
+            },
+    };
+
+    const std::vector<Operation> operations = {
+            {.type = OperationType::ADD, .inputs = {0, 4, 2}, .outputs = {3}},
+            {.type = OperationType::ADD, .inputs = {1, 3, 2}, .outputs = {4}},
+            {.type = OperationType::ADD, .inputs = {4, 0, 2}, .outputs = {5}},
+    };
+
+    Subgraph subgraph = {
+            .operands = operands,
+            .operations = operations,
+            .inputIndexes = {0, 1, 2},
+            .outputIndexes = {5},
+    };
+    const Model model = {
+            .main = std::move(subgraph),
+            .referenced = {},
+            .operandValues = {},
+            .pools = {},
+    };
+
+    // ensure that getSupportedOperations_1_2() checks model validity
+    ErrorStatus supportedOpsErrorStatus = ErrorStatus::GENERAL_FAILURE;
+    Return<void> supportedOpsReturn = kDevice->getSupportedOperations_1_3(
+            model, [&model, &supportedOpsErrorStatus](ErrorStatus status,
+                                                      const hidl_vec<bool>& supported) {
+                supportedOpsErrorStatus = status;
+                if (status == ErrorStatus::NONE) {
+                    ASSERT_EQ(supported.size(), model.main.operations.size());
+                }
+            });
+    ASSERT_TRUE(supportedOpsReturn.isOk());
+    ASSERT_EQ(supportedOpsErrorStatus, ErrorStatus::INVALID_ARGUMENT);
+
+    // ensure that prepareModel_1_3() checks model validity
+    sp<PreparedModelCallback> preparedModelCallback = new PreparedModelCallback;
+    Return<ErrorStatus> prepareLaunchReturn = kDevice->prepareModel_1_3(
+            model, ExecutionPreference::FAST_SINGLE_ANSWER, Priority::MEDIUM, {},
+            hidl_vec<hidl_handle>(), hidl_vec<hidl_handle>(), HidlToken(), preparedModelCallback);
+    ASSERT_TRUE(prepareLaunchReturn.isOk());
+    //     Note that preparation can fail for reasons other than an
+    //     invalid model (invalid model should result in
+    //     INVALID_ARGUMENT) -- for example, perhaps not all
+    //     operations are supported, or perhaps the device hit some
+    //     kind of capacity limit.
+    EXPECT_NE(prepareLaunchReturn, ErrorStatus::NONE);
+    EXPECT_NE(preparedModelCallback->getStatus(), ErrorStatus::NONE);
+    EXPECT_EQ(preparedModelCallback->getPreparedModel(), nullptr);
+}
+
 }  // namespace android::hardware::neuralnetworks::V1_3::vts::functional
diff --git a/neuralnetworks/1.3/vts/functional/Utils.cpp b/neuralnetworks/1.3/vts/functional/Utils.cpp
index 23e2af8..c460e11 100644
--- a/neuralnetworks/1.3/vts/functional/Utils.cpp
+++ b/neuralnetworks/1.3/vts/functional/Utils.cpp
@@ -17,11 +17,78 @@
 #include "1.3/Utils.h"
 
 #include <iostream>
+#include <numeric>
+#include "android-base/logging.h"
+#include "android/hardware/neuralnetworks/1.3/types.h"
 
-namespace android::hardware::neuralnetworks::V1_3 {
+namespace android::hardware::neuralnetworks {
+
+uint32_t sizeOfData(V1_3::OperandType type) {
+    switch (type) {
+        case V1_3::OperandType::FLOAT32:
+        case V1_3::OperandType::INT32:
+        case V1_3::OperandType::UINT32:
+        case V1_3::OperandType::TENSOR_FLOAT32:
+        case V1_3::OperandType::TENSOR_INT32:
+            return 4;
+        case V1_3::OperandType::TENSOR_QUANT16_SYMM:
+        case V1_3::OperandType::TENSOR_FLOAT16:
+        case V1_3::OperandType::FLOAT16:
+        case V1_3::OperandType::TENSOR_QUANT16_ASYMM:
+            return 2;
+        case V1_3::OperandType::TENSOR_QUANT8_ASYMM:
+        case V1_3::OperandType::BOOL:
+        case V1_3::OperandType::TENSOR_BOOL8:
+        case V1_3::OperandType::TENSOR_QUANT8_SYMM_PER_CHANNEL:
+        case V1_3::OperandType::TENSOR_QUANT8_SYMM:
+        case V1_3::OperandType::TENSOR_QUANT8_ASYMM_SIGNED:
+            return 1;
+        case V1_3::OperandType::SUBGRAPH:
+            return 0;
+        default:
+            CHECK(false) << "Invalid OperandType " << static_cast<uint32_t>(type);
+            return 0;
+    }
+}
+
+static bool isTensor(V1_3::OperandType type) {
+    switch (type) {
+        case V1_3::OperandType::FLOAT32:
+        case V1_3::OperandType::INT32:
+        case V1_3::OperandType::UINT32:
+        case V1_3::OperandType::FLOAT16:
+        case V1_3::OperandType::BOOL:
+        case V1_3::OperandType::SUBGRAPH:
+            return false;
+        case V1_3::OperandType::TENSOR_FLOAT32:
+        case V1_3::OperandType::TENSOR_INT32:
+        case V1_3::OperandType::TENSOR_QUANT16_SYMM:
+        case V1_3::OperandType::TENSOR_FLOAT16:
+        case V1_3::OperandType::TENSOR_QUANT16_ASYMM:
+        case V1_3::OperandType::TENSOR_QUANT8_ASYMM:
+        case V1_3::OperandType::TENSOR_BOOL8:
+        case V1_3::OperandType::TENSOR_QUANT8_SYMM_PER_CHANNEL:
+        case V1_3::OperandType::TENSOR_QUANT8_SYMM:
+        case V1_3::OperandType::TENSOR_QUANT8_ASYMM_SIGNED:
+            return true;
+        default:
+            CHECK(false) << "Invalid OperandType " << static_cast<uint32_t>(type);
+            return false;
+    }
+}
+
+uint32_t sizeOfData(const V1_3::Operand& operand) {
+    const uint32_t dataSize = sizeOfData(operand.type);
+    if (isTensor(operand.type) && operand.dimensions.size() == 0) return 0;
+    return std::accumulate(operand.dimensions.begin(), operand.dimensions.end(), dataSize,
+                           std::multiplies<>{});
+}
+
+namespace V1_3 {
 
 ::std::ostream& operator<<(::std::ostream& os, ErrorStatus errorStatus) {
     return os << toString(errorStatus);
 }
 
-}  // namespace android::hardware::neuralnetworks::V1_3
+}  // namespace V1_3
+}  // namespace android::hardware::neuralnetworks
diff --git a/neuralnetworks/1.3/vts/functional/ValidateModel.cpp b/neuralnetworks/1.3/vts/functional/ValidateModel.cpp
index e590fda..849ef7b 100644
--- a/neuralnetworks/1.3/vts/functional/ValidateModel.cpp
+++ b/neuralnetworks/1.3/vts/functional/ValidateModel.cpp
@@ -16,15 +16,22 @@
 
 #define LOG_TAG "neuralnetworks_hidl_hal_test"
 
+#include <android/hardware/neuralnetworks/1.1/types.h>
+#include <android/hardware/neuralnetworks/1.3/types.h>
 #include "1.0/Utils.h"
 #include "1.3/Callbacks.h"
 #include "1.3/Utils.h"
 #include "GeneratedTestHarness.h"
 #include "VtsHalNeuralnetworks.h"
 
+#include <optional>
+#include <type_traits>
+#include <utility>
+
 namespace android::hardware::neuralnetworks::V1_3::vts::functional {
 
 using implementation::PreparedModelCallback;
+using V1_0::DataLocation;
 using V1_1::ExecutionPreference;
 using V1_2::SymmPerChannelQuantParams;
 using HidlToken =
@@ -112,6 +119,262 @@
     return index;
 }
 
+// If we introduce a CONSTANT_COPY for an operand of size operandSize,
+// how much will this increase the size of the model?  This assumes
+// that we can (re)use all of model.operandValues for the operand
+// value.
+static size_t constantCopyExtraSize(const Model& model, size_t operandSize) {
+    const size_t operandValuesSize = model.operandValues.size();
+    return (operandValuesSize < operandSize) ? (operandSize - operandValuesSize) : 0;
+}
+
+// Highly specialized utility routine for converting an operand to
+// CONSTANT_COPY lifetime.
+//
+// Expects that:
+// - operand has a known size
+// - operand->lifetime has already been set to CONSTANT_COPY
+// - operand->location has been zeroed out
+//
+// Does the following:
+// - initializes operand->location to point to the beginning of model->operandValues
+// - resizes model->operandValues (if necessary) to be large enough for the operand
+//   value, padding it with zeroes on the end
+//
+// Potential problem:
+// By changing the operand to CONSTANT_COPY lifetime, this function is effectively initializing the
+// operand with unspecified (but deterministic) data. This means that the model may be invalidated
+// in two ways: not only is the lifetime of CONSTANT_COPY invalid, but the operand's value in the
+// graph may also be invalid (e.g., if the operand is used as an activation code and has an invalid
+// value). For now, this should be fine because it just means we're not testing what we think we're
+// testing in certain cases; but we can handwave this and assume we're probabilistically likely to
+// exercise the validation code over the span of the entire test set and operand space.
+//
+// Aborts if the specified operand type is an extension type or OEM type.
+static void becomeConstantCopy(Model* model, Operand* operand) {
+    // sizeOfData will abort if the specified type is an extension type or OEM type.
+    const size_t sizeOfOperand = sizeOfData(*operand);
+    EXPECT_NE(sizeOfOperand, size_t(0));
+    operand->location.poolIndex = 0;
+    operand->location.offset = 0;
+    operand->location.length = sizeOfOperand;
+    if (model->operandValues.size() < sizeOfOperand) {
+        model->operandValues.resize(sizeOfOperand);
+    }
+}
+
+// The sizeForBinder() functions estimate the size of the
+// representation of a value when sent to binder.  It's probably a bit
+// of an under-estimate, because we don't know the size of the
+// metadata in the binder format (e.g., representation of the size of
+// a vector); but at least it adds up "big" things like vector
+// contents.  However, it doesn't treat inter-field or end-of-struct
+// padding in a methodical way -- there's no attempt to be consistent
+// in whether or not padding in the native (C++) representation
+// contributes to the estimated size for the binder representation;
+// and there's no attempt to understand what padding (if any) is
+// needed in the binder representation.
+//
+// This assumes that non-metadata uses a fixed length encoding (e.g.,
+// a uint32_t is always encoded in sizeof(uint32_t) bytes, rather than
+// using an encoding whose length is related to the magnitude of the
+// encoded value).
+
+template <typename Type>
+static size_t sizeForBinder(const Type& val) {
+    static_assert(std::is_trivially_copyable_v<std::remove_reference_t<Type>>,
+                  "expected a trivially copyable type");
+    return sizeof(val);
+}
+
+template <typename Type>
+static size_t sizeForBinder(const hidl_vec<Type>& vec) {
+    return std::accumulate(vec.begin(), vec.end(), 0,
+                           [](size_t acc, const Type& x) { return acc + sizeForBinder(x); });
+}
+
+template <>
+size_t sizeForBinder(const SymmPerChannelQuantParams& symmPerChannelQuantParams) {
+    size_t size = 0;
+
+    size += sizeForBinder(symmPerChannelQuantParams.scales);
+    size += sizeForBinder(symmPerChannelQuantParams.channelDim);
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const V1_2::Operand::ExtraParams& extraParams) {
+    using Discriminator = V1_2::Operand::ExtraParams::hidl_discriminator;
+    switch (extraParams.getDiscriminator()) {
+        case Discriminator::none:
+            return 0;
+        case Discriminator::channelQuant:
+            return sizeForBinder(extraParams.channelQuant());
+        case Discriminator::extension:
+            return sizeForBinder(extraParams.extension());
+    }
+    LOG(FATAL) << "Unrecognized extraParams enum: "
+               << static_cast<int>(extraParams.getDiscriminator());
+    return 0;
+}
+
+template <>
+size_t sizeForBinder(const Operand& operand) {
+    size_t size = 0;
+
+    size += sizeForBinder(operand.type);
+    size += sizeForBinder(operand.dimensions);
+    size += sizeForBinder(operand.numberOfConsumers);
+    size += sizeForBinder(operand.scale);
+    size += sizeForBinder(operand.zeroPoint);
+    size += sizeForBinder(operand.lifetime);
+    size += sizeForBinder(operand.location);
+    size += sizeForBinder(operand.extraParams);
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const Operation& operation) {
+    size_t size = 0;
+
+    size += sizeForBinder(operation.type);
+    size += sizeForBinder(operation.inputs);
+    size += sizeForBinder(operation.outputs);
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const hidl_string& name) {
+    return name.size();
+}
+
+template <>
+size_t sizeForBinder(const hidl_memory& memory) {
+    // This is just a guess.
+
+    size_t size = 0;
+
+    if (const native_handle_t* handle = memory.handle()) {
+        size += sizeof(*handle);
+        size += sizeof(handle->data[0] * (handle->numFds + handle->numInts));
+    }
+    size += sizeForBinder(memory.name());
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const Subgraph& subgraph) {
+    size_t size = 0;
+
+    size += sizeForBinder(subgraph.operands);
+    size += sizeForBinder(subgraph.operations);
+    size += sizeForBinder(subgraph.inputIndexes);
+    size += sizeForBinder(subgraph.outputIndexes);
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const V1_2::Model::ExtensionNameAndPrefix& extensionNameToPrefix) {
+    size_t size = 0;
+
+    size += sizeForBinder(extensionNameToPrefix.name);
+    size += sizeForBinder(extensionNameToPrefix.prefix);
+
+    return size;
+}
+
+template <>
+size_t sizeForBinder(const Model& model) {
+    size_t size = 0;
+
+    size += sizeForBinder(model.main);
+    size += sizeForBinder(model.referenced);
+    size += sizeForBinder(model.operandValues);
+    size += sizeForBinder(model.pools);
+    size += sizeForBinder(model.relaxComputationFloat32toFloat16);
+    size += sizeForBinder(model.extensionNameToPrefix);
+
+    return size;
+}
+
+// https://developer.android.com/reference/android/os/TransactionTooLargeException.html
+//
+//     "The Binder transaction buffer has a limited fixed size,
+//     currently 1Mb, which is shared by all transactions in progress
+//     for the process."
+//
+// Will our representation fit under this limit?  There are two complications:
+// - Our representation size is just approximate (see sizeForBinder()).
+// - This object may not be the only occupant of the Binder transaction buffer.
+// So we'll be very conservative: We want the representation size to be no
+// larger than half the transaction buffer size.
+//
+// If our representation grows large enough that it still fits within
+// the transaction buffer but combined with other transactions may
+// exceed the buffer size, then we may see intermittent HAL transport
+// errors.
+static bool exceedsBinderSizeLimit(size_t representationSize) {
+    // Instead of using this fixed buffer size, we might instead be able to use
+    // ProcessState::self()->getMmapSize(). However, this has a potential
+    // problem: The binder/mmap size of the current process does not necessarily
+    // indicate the binder/mmap size of the service (i.e., the other process).
+    // The only way it would be a good indication is if both the current process
+    // and the service use the default size.
+    static const size_t kHalfBufferSize = 1024 * 1024 / 2;
+
+    return representationSize > kHalfBufferSize;
+}
+
+///////////////////////// VALIDATE EXECUTION ORDER ////////////////////////////
+
+static void mutateExecutionOrderTest(const sp<IDevice>& device, const Model& model) {
+    for (size_t operation = 0; operation < model.main.operations.size(); ++operation) {
+        const Operation& operationObj = model.main.operations[operation];
+        for (uint32_t input : operationObj.inputs) {
+            if (model.main.operands[input].lifetime == OperandLifeTime::TEMPORARY_VARIABLE ||
+                model.main.operands[input].lifetime == OperandLifeTime::SUBGRAPH_OUTPUT) {
+                // This operation reads an operand written by some
+                // other operation.  Move this operation to the
+                // beginning of the sequence, ensuring that it reads
+                // the operand before that operand is written, thereby
+                // violating execution order rules.
+                const std::string message = "mutateExecutionOrderTest: operation " +
+                                            std::to_string(operation) + " is a reader";
+                validate(device, message, model,
+                         [operation](Model* model, ExecutionPreference*, Priority*) {
+                             auto& operations = model->main.operations;
+                             std::rotate(operations.begin(), operations.begin() + operation,
+                                         operations.begin() + operation + 1);
+                         });
+                break;  // only need to do this once per operation
+            }
+        }
+        for (uint32_t output : operationObj.outputs) {
+            if (model.main.operands[output].numberOfConsumers > 0) {
+                // This operation writes an operand read by some other
+                // operation.  Move this operation to the end of the
+                // sequence, ensuring that it writes the operand after
+                // that operand is read, thereby violating execution
+                // order rules.
+                const std::string message = "mutateExecutionOrderTest: operation " +
+                                            std::to_string(operation) + " is a writer";
+                validate(device, message, model,
+                         [operation](Model* model, ExecutionPreference*, Priority*) {
+                             auto& operations = model->main.operations;
+                             std::rotate(operations.begin() + operation,
+                                         operations.begin() + operation + 1, operations.end());
+                         });
+                break;  // only need to do this once per operation
+            }
+        }
+    }
+}
+
 ///////////////////////// VALIDATE MODEL OPERAND TYPE /////////////////////////
 
 static const uint32_t invalidOperandTypes[] = {
@@ -261,9 +524,245 @@
     }
 }
 
+///////////////////////// VALIDATE OPERAND LIFETIME /////////////////////////////////////////////
+
+static std::vector<OperandLifeTime> getInvalidLifeTimes(const Model& model, size_t modelSize,
+                                                        const Operand& operand) {
+    // TODO: Support OperandLifeTime::CONSTANT_REFERENCE as an invalid lifetime
+    // TODO: Support OperandLifeTime::NO_VALUE as an invalid lifetime
+
+    // Ways to get an invalid lifetime:
+    // - change whether a lifetime means an operand should have a writer
+    std::vector<OperandLifeTime> ret;
+    switch (operand.lifetime) {
+        case OperandLifeTime::SUBGRAPH_OUTPUT:
+        case OperandLifeTime::TEMPORARY_VARIABLE:
+            ret = {
+                    OperandLifeTime::SUBGRAPH_INPUT,
+                    OperandLifeTime::CONSTANT_COPY,
+            };
+            break;
+        case OperandLifeTime::CONSTANT_COPY:
+        case OperandLifeTime::CONSTANT_REFERENCE:
+        case OperandLifeTime::SUBGRAPH_INPUT:
+            ret = {
+                    OperandLifeTime::TEMPORARY_VARIABLE,
+                    OperandLifeTime::SUBGRAPH_OUTPUT,
+            };
+            break;
+        case OperandLifeTime::NO_VALUE:
+            // Not enough information to know whether
+            // TEMPORARY_VARIABLE or CONSTANT_COPY would be invalid --
+            // is this operand written (then CONSTANT_COPY would be
+            // invalid) or not (then TEMPORARY_VARIABLE would be
+            // invalid)?
+            break;
+        case OperandLifeTime::SUBGRAPH:
+            break;
+        default:
+            ADD_FAILURE();
+            break;
+    }
+
+    const size_t operandSize = sizeOfData(operand);  // will be zero if shape is unknown
+    if (!operandSize ||
+        exceedsBinderSizeLimit(modelSize + constantCopyExtraSize(model, operandSize))) {
+        // Unknown size or too-large size
+        ret.erase(std::remove(ret.begin(), ret.end(), OperandLifeTime::CONSTANT_COPY), ret.end());
+    }
+
+    return ret;
+}
+
+static void mutateOperandLifeTimeTest(const sp<IDevice>& device, const Model& model) {
+    const size_t modelSize = sizeForBinder(model);
+    for (size_t operand = 0; operand < model.main.operands.size(); ++operand) {
+        const std::vector<OperandLifeTime> invalidLifeTimes =
+                getInvalidLifeTimes(model, modelSize, model.main.operands[operand]);
+        for (OperandLifeTime invalidLifeTime : invalidLifeTimes) {
+            const std::string message = "mutateOperandLifetimeTest: operand " +
+                                        std::to_string(operand) + " has lifetime " +
+                                        toString(invalidLifeTime) + " instead of lifetime " +
+                                        toString(model.main.operands[operand].lifetime);
+            validate(device, message, model,
+                     [operand, invalidLifeTime](Model* model, ExecutionPreference*, Priority*) {
+                         static const DataLocation kZeroDataLocation = {};
+                         Operand& operandObj = model->main.operands[operand];
+                         switch (operandObj.lifetime) {
+                             case OperandLifeTime::SUBGRAPH_INPUT: {
+                                 hidl_vec_remove(&model->main.inputIndexes, uint32_t(operand));
+                                 break;
+                             }
+                             case OperandLifeTime::SUBGRAPH_OUTPUT: {
+                                 hidl_vec_remove(&model->main.outputIndexes, uint32_t(operand));
+                                 break;
+                             }
+                             default:
+                                 break;
+                         }
+                         operandObj.lifetime = invalidLifeTime;
+                         operandObj.location = kZeroDataLocation;
+                         switch (invalidLifeTime) {
+                             case OperandLifeTime::CONSTANT_COPY: {
+                                 becomeConstantCopy(model, &operandObj);
+                                 break;
+                             }
+                             case OperandLifeTime::SUBGRAPH_INPUT:
+                                 hidl_vec_push_back(&model->main.inputIndexes, uint32_t(operand));
+                                 break;
+                             case OperandLifeTime::SUBGRAPH_OUTPUT:
+                                 hidl_vec_push_back(&model->main.outputIndexes, uint32_t(operand));
+                                 break;
+                             default:
+                                 break;
+                         }
+                     });
+        }
+    }
+}
+
+///////////////////////// VALIDATE OPERAND INPUT-or-OUTPUT //////////////////////////////////////
+
+static std::optional<OperandLifeTime> getInputOutputLifeTime(const Model& model, size_t modelSize,
+                                                             const Operand& operand) {
+    // Ways to get an invalid lifetime (with respect to model inputIndexes and outputIndexes):
+    // - change whether a lifetime means an operand is a model input, a model output, or neither
+    // - preserve whether or not a lifetime means an operand should have a writer
+    switch (operand.lifetime) {
+        case OperandLifeTime::CONSTANT_COPY:
+        case OperandLifeTime::CONSTANT_REFERENCE:
+            return OperandLifeTime::SUBGRAPH_INPUT;
+        case OperandLifeTime::SUBGRAPH_INPUT: {
+            const size_t operandSize = sizeOfData(operand);  // will be zero if shape is unknown
+            if (!operandSize ||
+                exceedsBinderSizeLimit(modelSize + constantCopyExtraSize(model, operandSize))) {
+                // Unknown size or too-large size
+                break;
+            }
+            return OperandLifeTime::CONSTANT_COPY;
+        }
+        case OperandLifeTime::SUBGRAPH_OUTPUT:
+            return OperandLifeTime::TEMPORARY_VARIABLE;
+        case OperandLifeTime::TEMPORARY_VARIABLE:
+            return OperandLifeTime::SUBGRAPH_OUTPUT;
+        case OperandLifeTime::NO_VALUE:
+            // Not enough information to know whether
+            // TEMPORARY_VARIABLE or CONSTANT_COPY would be an
+            // appropriate choice -- is this operand written (then
+            // TEMPORARY_VARIABLE would be appropriate) or not (then
+            // CONSTANT_COPY would be appropriate)?
+            break;
+        case OperandLifeTime::SUBGRAPH:
+            break;
+        default:
+            ADD_FAILURE();
+            break;
+    }
+
+    return std::nullopt;
+}
+
+static void mutateOperandInputOutputTest(const sp<IDevice>& device, const Model& model) {
+    const size_t modelSize = sizeForBinder(model);
+    for (size_t operand = 0; operand < model.main.operands.size(); ++operand) {
+        const std::optional<OperandLifeTime> changedLifeTime =
+                getInputOutputLifeTime(model, modelSize, model.main.operands[operand]);
+        if (changedLifeTime) {
+            const std::string message = "mutateOperandInputOutputTest: operand " +
+                                        std::to_string(operand) + " has lifetime " +
+                                        toString(*changedLifeTime) + " instead of lifetime " +
+                                        toString(model.main.operands[operand].lifetime);
+            validate(device, message, model,
+                     [operand, changedLifeTime](Model* model, ExecutionPreference*, Priority*) {
+                         static const DataLocation kZeroDataLocation = {};
+                         Operand& operandObj = model->main.operands[operand];
+                         operandObj.lifetime = *changedLifeTime;
+                         operandObj.location = kZeroDataLocation;
+                         if (*changedLifeTime == OperandLifeTime::CONSTANT_COPY) {
+                             becomeConstantCopy(model, &operandObj);
+                         }
+                     });
+        }
+    }
+}
+
+///////////////////////// VALIDATE OPERAND NUMBER OF CONSUMERS //////////////////////////////////
+
+static std::vector<uint32_t> getInvalidNumberOfConsumers(uint32_t numberOfConsumers) {
+    if (numberOfConsumers == 0) {
+        return {1};
+    } else {
+        return {numberOfConsumers - 1, numberOfConsumers + 1};
+    }
+}
+
+static void mutateOperandNumberOfConsumersTest(const sp<IDevice>& device, const Model& model) {
+    for (size_t operand = 0; operand < model.main.operands.size(); ++operand) {
+        const std::vector<uint32_t> invalidNumberOfConsumersVec =
+                getInvalidNumberOfConsumers(model.main.operands[operand].numberOfConsumers);
+        for (uint32_t invalidNumberOfConsumers : invalidNumberOfConsumersVec) {
+            const std::string message =
+                    "mutateOperandNumberOfConsumersTest: operand " + std::to_string(operand) +
+                    " numberOfConsumers = " + std::to_string(invalidNumberOfConsumers);
+            validate(device, message, model,
+                     [operand, invalidNumberOfConsumers](Model* model, ExecutionPreference*,
+                                                         Priority*) {
+                         model->main.operands[operand].numberOfConsumers = invalidNumberOfConsumers;
+                     });
+        }
+    }
+}
+
+///////////////////////// VALIDATE OPERAND NUMBER OF WRITERS ////////////////////////////////////
+
+static void mutateOperandAddWriterTest(const sp<IDevice>& device, const Model& model) {
+    for (size_t operation = 0; operation < model.main.operations.size(); ++operation) {
+        for (size_t badOutputNum = 0;
+             badOutputNum < model.main.operations[operation].outputs.size(); ++badOutputNum) {
+            const uint32_t outputOperandIndex =
+                    model.main.operations[operation].outputs[badOutputNum];
+            const std::string message = "mutateOperandAddWriterTest: operation " +
+                                        std::to_string(operation) + " writes to " +
+                                        std::to_string(outputOperandIndex);
+            // We'll insert a copy of the operation, all of whose
+            // OTHER output operands are newly-created -- i.e.,
+            // there'll only be a duplicate write of ONE of that
+            // operation's output operands.
+            validate(device, message, model,
+                     [operation, badOutputNum](Model* model, ExecutionPreference*, Priority*) {
+                         Operation newOperation = model->main.operations[operation];
+                         for (uint32_t input : newOperation.inputs) {
+                             ++model->main.operands[input].numberOfConsumers;
+                         }
+                         for (size_t outputNum = 0; outputNum < newOperation.outputs.size();
+                              ++outputNum) {
+                             if (outputNum == badOutputNum) continue;
+
+                             Operand operandValue =
+                                     model->main.operands[newOperation.outputs[outputNum]];
+                             operandValue.numberOfConsumers = 0;
+                             if (operandValue.lifetime == OperandLifeTime::SUBGRAPH_OUTPUT) {
+                                 operandValue.lifetime = OperandLifeTime::TEMPORARY_VARIABLE;
+                             } else {
+                                 ASSERT_EQ(operandValue.lifetime,
+                                           OperandLifeTime::TEMPORARY_VARIABLE);
+                             }
+                             newOperation.outputs[outputNum] =
+                                     hidl_vec_push_back(&model->main.operands, operandValue);
+                         }
+                         // Where do we insert the extra writer (a new
+                         // operation)?  It has to be later than all the
+                         // writers of its inputs.  The easiest thing to do
+                         // is to insert it at the end of the operation
+                         // sequence.
+                         hidl_vec_push_back(&model->main.operations, newOperation);
+                     });
+        }
+    }
+}
+
 ///////////////////////// VALIDATE EXTRA ??? /////////////////////////
 
-// TODO: Operand::lifetime
 // TODO: Operand::location
 
 ///////////////////////// VALIDATE OPERATION OPERAND TYPE /////////////////////////
@@ -511,6 +1010,37 @@
     }
 }
 
+///////////////////////// VALIDATE MODEL OPERANDS WRITTEN ///////////////////////////////////////
+
+static void mutateOperationRemoveWriteTest(const sp<IDevice>& device, const Model& model) {
+    for (size_t operation = 0; operation < model.main.operations.size(); ++operation) {
+        for (size_t outputNum = 0; outputNum < model.main.operations[operation].outputs.size();
+             ++outputNum) {
+            const uint32_t outputOperandIndex = model.main.operations[operation].outputs[outputNum];
+            if (model.main.operands[outputOperandIndex].numberOfConsumers > 0) {
+                const std::string message = "mutateOperationRemoveWriteTest: operation " +
+                                            std::to_string(operation) + " writes to " +
+                                            std::to_string(outputOperandIndex);
+                validate(device, message, model,
+                         [operation, outputNum](Model* model, ExecutionPreference*, Priority*) {
+                             uint32_t& outputOperandIndex =
+                                     model->main.operations[operation].outputs[outputNum];
+                             Operand operandValue = model->main.operands[outputOperandIndex];
+                             operandValue.numberOfConsumers = 0;
+                             if (operandValue.lifetime == OperandLifeTime::SUBGRAPH_OUTPUT) {
+                                 operandValue.lifetime = OperandLifeTime::TEMPORARY_VARIABLE;
+                             } else {
+                                 ASSERT_EQ(operandValue.lifetime,
+                                           OperandLifeTime::TEMPORARY_VARIABLE);
+                             }
+                             outputOperandIndex =
+                                     hidl_vec_push_back(&model->main.operands, operandValue);
+                         });
+            }
+        }
+    }
+}
+
 ///////////////////////// REMOVE OPERAND FROM EVERYTHING /////////////////////////
 
 static void removeValueAndDecrementGreaterValues(hidl_vec<uint32_t>* vec, uint32_t value) {
@@ -804,14 +1334,20 @@
 ////////////////////////// ENTRY POINT //////////////////////////////
 
 void validateModel(const sp<IDevice>& device, const Model& model) {
+    mutateExecutionOrderTest(device, model);
     mutateOperandTypeTest(device, model);
     mutateOperandRankTest(device, model);
     mutateOperandScaleTest(device, model);
     mutateOperandZeroPointTest(device, model);
+    mutateOperandLifeTimeTest(device, model);
+    mutateOperandInputOutputTest(device, model);
+    mutateOperandNumberOfConsumersTest(device, model);
+    mutateOperandAddWriterTest(device, model);
     mutateOperationOperandTypeTest(device, model);
     mutateOperationTypeTest(device, model);
     mutateOperationInputOperandIndexTest(device, model);
     mutateOperationOutputOperandIndexTest(device, model);
+    mutateOperationRemoveWriteTest(device, model);
     removeOperandTest(device, model);
     removeOperationTest(device, model);
     removeOperationInputTest(device, model);
diff --git a/neuralnetworks/1.3/vts/functional/include/1.3/Utils.h b/neuralnetworks/1.3/vts/functional/include/1.3/Utils.h
index 3661b66..e07e73b 100644
--- a/neuralnetworks/1.3/vts/functional/include/1.3/Utils.h
+++ b/neuralnetworks/1.3/vts/functional/include/1.3/Utils.h
@@ -24,6 +24,18 @@
 
 inline constexpr V1_3::Priority kDefaultPriority = V1_3::Priority::MEDIUM;
 
+// Returns the amount of space needed to store a value of the specified type.
+//
+// Aborts if the specified type is an extension type or OEM type.
+uint32_t sizeOfData(V1_3::OperandType type);
+
+// Returns the amount of space needed to store a value of the dimensions and
+// type of this operand. For a non-extension, non-OEM tensor with unspecified
+// rank or at least one unspecified dimension, returns zero.
+//
+// Aborts if the specified type is an extension type or OEM type.
+uint32_t sizeOfData(const V1_3::Operand& operand);
+
 }  // namespace android::hardware::neuralnetworks
 
 namespace android::hardware::neuralnetworks::V1_3 {
diff --git a/sensors/1.0/vts/functional/Android.bp b/sensors/1.0/vts/functional/Android.bp
index 1167fd4..d1b8cc7 100644
--- a/sensors/1.0/vts/functional/Android.bp
+++ b/sensors/1.0/vts/functional/Android.bp
@@ -31,6 +31,9 @@
         "android.hardware.sensors@1.0",
         "VtsHalSensorsTargetTestUtils",
     ],
-    test_suites: ["general-tests", "vts-core"],
+    test_suites: [
+        "general-tests",
+        "vts"
+    ],
 }
 
diff --git a/sensors/2.0/multihal/HalProxy.cpp b/sensors/2.0/multihal/HalProxy.cpp
index ac6f17a..fbff24c 100644
--- a/sensors/2.0/multihal/HalProxy.cpp
+++ b/sensors/2.0/multihal/HalProxy.cpp
@@ -360,7 +360,7 @@
     } else {
         std::string subHalLibraryFile;
         while (subHalConfigStream >> subHalLibraryFile) {
-            void* handle = dlopen(subHalLibraryFile.c_str(), RTLD_NOW);
+            void* handle = getHandleForSubHalSharedObject(subHalLibraryFile);
             if (handle == nullptr) {
                 ALOGE("dlopen failed for library: %s", subHalLibraryFile.c_str());
             } else {
@@ -415,6 +415,25 @@
     }
 }
 
+void* HalProxy::getHandleForSubHalSharedObject(const std::string& filename) {
+    static const std::string kSubHalShareObjectLocations[] = {
+            "",  // Default locations will be searched
+#ifdef __LP64__
+            "/vendor/lib64/hw/", "/odm/lib64/", "/odm/lib64/hw/"
+#else
+            "/vendor/lib/hw/", "/odm/lib/", "/odm/lib/hw/"
+#endif
+    };
+
+    for (const std::string& dir : kSubHalShareObjectLocations) {
+        void* handle = dlopen((dir + filename).c_str(), RTLD_NOW);
+        if (handle != nullptr) {
+            return handle;
+        }
+    }
+    return nullptr;
+}
+
 void HalProxy::init() {
     initializeSubHalCallbacks();
     initializeSensorList();
diff --git a/sensors/2.0/multihal/include/HalProxy.h b/sensors/2.0/multihal/include/HalProxy.h
index 978f7cf..10bba55 100644
--- a/sensors/2.0/multihal/include/HalProxy.h
+++ b/sensors/2.0/multihal/include/HalProxy.h
@@ -262,6 +262,16 @@
     void initializeSensorList();
 
     /**
+     * Try using the default include directories as well as the directories defined in
+     * kSubHalShareObjectLocations to get a handle for dlsym for a subhal.
+     *
+     * @param filename The file name to search for.
+     *
+     * @return The handle or nullptr if search failed.
+     */
+    void* getHandleForSubHalSharedObject(const std::string& filename);
+
+    /**
      * Calls the helper methods that all ctors use.
      */
     void init();
diff --git a/sensors/2.0/vts/functional/VtsHalSensorsV2_0TargetTest.cpp b/sensors/2.0/vts/functional/VtsHalSensorsV2_0TargetTest.cpp
index d0ebe4d..e46f034 100644
--- a/sensors/2.0/vts/functional/VtsHalSensorsV2_0TargetTest.cpp
+++ b/sensors/2.0/vts/functional/VtsHalSensorsV2_0TargetTest.cpp
@@ -320,11 +320,13 @@
                          << s.sensorHandle << std::dec << " type=" << static_cast<int>(s.type)
                          << " name=" << s.name);
 
-            // Test non-empty type string
-            EXPECT_FALSE(s.typeAsString.empty());
-
-            // Test defined type matches defined string type
-            EXPECT_NO_FATAL_FAILURE(assertTypeMatchStringType(s.type, s.typeAsString));
+            // Test type string non-empty only for private sensor types.
+            if (s.type >= SensorType::DEVICE_PRIVATE_BASE) {
+                EXPECT_FALSE(s.typeAsString.empty());
+            } else if (!s.typeAsString.empty()) {
+                // Test type string matches framework string if specified for non-private types.
+                EXPECT_NO_FATAL_FAILURE(assertTypeMatchStringType(s.type, s.typeAsString));
+            }
 
             // Test if all sensor has name and vendor
             EXPECT_FALSE(s.name.empty());