diff --git a/audio/aidl/default/Module.cpp b/audio/aidl/default/Module.cpp
index 3117134..819b3c5 100644
--- a/audio/aidl/default/Module.cpp
+++ b/audio/aidl/default/Module.cpp
@@ -1277,6 +1277,12 @@
             mmapSources.insert(port.id);
         }
     }
+    if (mmapSources.empty() && mmapSinks.empty()) {
+        AudioMMapPolicyInfo never;
+        never.mmapPolicy = AudioMMapPolicy::NEVER;
+        _aidl_return->push_back(never);
+        return ndk::ScopedAStatus::ok();
+    }
     for (const auto& route : getConfig().routes) {
         if (mmapSinks.count(route.sinkPortId) != 0) {
             // The sink is a mix port, add the sources if they are device ports.
diff --git a/audio/aidl/vts/VtsHalAudioCoreModuleTargetTest.cpp b/audio/aidl/vts/VtsHalAudioCoreModuleTargetTest.cpp
index ccf7cfc..a4670db 100644
--- a/audio/aidl/vts/VtsHalAudioCoreModuleTargetTest.cpp
+++ b/audio/aidl/vts/VtsHalAudioCoreModuleTargetTest.cpp
@@ -87,6 +87,7 @@
 using aidl::android::media::audio::common::AudioFormatType;
 using aidl::android::media::audio::common::AudioIoFlags;
 using aidl::android::media::audio::common::AudioLatencyMode;
+using aidl::android::media::audio::common::AudioMMapPolicy;
 using aidl::android::media::audio::common::AudioMMapPolicyInfo;
 using aidl::android::media::audio::common::AudioMMapPolicyType;
 using aidl::android::media::audio::common::AudioMode;
@@ -2133,7 +2134,13 @@
         std::vector<AudioMMapPolicyInfo> policyInfos;
         EXPECT_IS_OK(module->getMmapPolicyInfos(mmapPolicyType, &policyInfos))
                 << toString(mmapPolicyType);
-        EXPECT_EQ(isMmapSupported, !policyInfos.empty());
+        const bool isMMapSupportedByPolicyInfos =
+                std::find_if(policyInfos.begin(), policyInfos.end(), [](const auto& info) {
+                    return info.mmapPolicy == AudioMMapPolicy::AUTO ||
+                           info.mmapPolicy == AudioMMapPolicy::ALWAYS;
+                }) != policyInfos.end();
+        EXPECT_EQ(isMmapSupported, isMMapSupportedByPolicyInfos)
+                << ::android::internal::ToString(policyInfos);
     }
 }
 
@@ -4172,58 +4179,32 @@
 class WithRemoteSubmix {
   public:
     WithRemoteSubmix() = default;
-    WithRemoteSubmix(AudioDeviceAddress address) : mAddress(address) {}
+    explicit WithRemoteSubmix(AudioDeviceAddress address) : mAddress(address) {}
     WithRemoteSubmix(const WithRemoteSubmix&) = delete;
     WithRemoteSubmix& operator=(const WithRemoteSubmix&) = delete;
-    std::optional<AudioPort> getAudioPort() {
+    static std::optional<AudioPort> getRemoteSubmixAudioPort(
+            ModuleConfig* moduleConfig,
+            const std::optional<AudioDeviceAddress>& address = std::nullopt) {
         AudioDeviceType deviceType = IOTraits<Stream>::is_input ? AudioDeviceType::IN_SUBMIX
                                                                 : AudioDeviceType::OUT_SUBMIX;
-        auto ports = mModuleConfig->getAudioPortsForDeviceTypes(
+        auto ports = moduleConfig->getAudioPortsForDeviceTypes(
                 std::vector<AudioDeviceType>{deviceType},
                 AudioDeviceDescription::CONNECTION_VIRTUAL);
-        if (!ports.empty()) return ports.front();
-        return {};
-    }
-    /* Connect remote submix external device */
-    void SetUpPortConnection() {
-        auto port = getAudioPort();
-        ASSERT_TRUE(port.has_value()) << "Device AudioPort for remote submix not found";
-        if (mAddress.has_value()) {
-            port.value().ext.template get<AudioPortExt::Tag::device>().device.address =
-                    mAddress.value();
+        if (ports.empty()) return {};
+        AudioPort port = ports.front();
+        if (address) {
+            port.ext.template get<AudioPortExt::Tag::device>().device.address = address.value();
         } else {
-            port = GenerateUniqueDeviceAddress(port.value());
+            port = GenerateUniqueDeviceAddress(port);
         }
-        mConnectedPort = std::make_unique<WithDevicePortConnectedState>(port.value());
-        ASSERT_NO_FATAL_FAILURE(mConnectedPort->SetUp(mModule, mModuleConfig));
+        return port;
     }
-    AudioDeviceAddress getAudioDeviceAddress() {
-        if (!mAddress.has_value()) {
-            mAddress = mConnectedPort->get()
-                               .ext.template get<AudioPortExt::Tag::device>()
-                               .device.address;
-        }
-        return mAddress.value();
-    }
-    /* Get mix port config for stream and setup patch for it. */
-    void SetupPatch() {
-        const auto portConfig =
-                mModuleConfig->getSingleConfigForMixPort(IOTraits<Stream>::is_input);
-        if (!portConfig.has_value()) {
-            LOG(DEBUG) << __func__ << ": portConfig not found";
-            mSkipTest = true;
-            return;
-        }
-        auto devicePortConfig = mModuleConfig->getSingleConfigForDevicePort(mConnectedPort->get());
-        mPatch = std::make_unique<WithAudioPatch>(IOTraits<Stream>::is_input, portConfig.value(),
-                                                  devicePortConfig);
-        ASSERT_NO_FATAL_FAILURE(mPatch->SetUp(mModule));
-    }
-    void SetUp(IModule* module, ModuleConfig* moduleConfig) {
+    std::optional<AudioDeviceAddress> getAudioDeviceAddress() const { return mAddress; }
+    void SetUp(IModule* module, ModuleConfig* moduleConfig, const AudioPort& connectedPort) {
         mModule = module;
         mModuleConfig = moduleConfig;
-        ASSERT_NO_FATAL_FAILURE(SetUpPortConnection());
-        ASSERT_NO_FATAL_FAILURE(SetupPatch());
+
+        ASSERT_NO_FATAL_FAILURE(SetupPatch(connectedPort));
         if (!mSkipTest) {
             // open stream
             mStream = std::make_unique<WithStream<Stream>>(
@@ -4231,6 +4212,11 @@
             ASSERT_NO_FATAL_FAILURE(
                     mStream->SetUp(mModule, AudioCoreModuleBase::kDefaultBufferSizeFrames));
         }
+        mAddress = connectedPort.ext.template get<AudioPortExt::Tag::device>().device.address;
+    }
+    void SetUp(IModule* module, ModuleConfig* moduleConfig) {
+        ASSERT_NO_FATAL_FAILURE(SetUpPortConnection(module, moduleConfig));
+        SetUp(module, moduleConfig, mConnectedPort->get());
     }
     void sendBurstCommands() {
         const StreamContext* context = mStream->getContext();
@@ -4248,9 +4234,31 @@
         }
         EXPECT_FALSE(driver.hasRetrogradeObservablePosition());
     }
-    bool skipTest() { return mSkipTest; }
+    bool skipTest() const { return mSkipTest; }
 
   private:
+    /* Connect remote submix external device */
+    void SetUpPortConnection(IModule* module, ModuleConfig* moduleConfig) {
+        auto port = getRemoteSubmixAudioPort(moduleConfig, mAddress);
+        ASSERT_TRUE(port.has_value()) << "Device AudioPort for remote submix not found";
+        mConnectedPort = std::make_unique<WithDevicePortConnectedState>(port.value());
+        ASSERT_NO_FATAL_FAILURE(mConnectedPort->SetUp(module, moduleConfig));
+    }
+    /* Get mix port config for stream and setup patch for it. */
+    void SetupPatch(const AudioPort& connectedPort) {
+        const auto portConfig =
+                mModuleConfig->getSingleConfigForMixPort(IOTraits<Stream>::is_input);
+        if (!portConfig.has_value()) {
+            LOG(DEBUG) << __func__ << ": portConfig not found";
+            mSkipTest = true;
+            return;
+        }
+        auto devicePortConfig = mModuleConfig->getSingleConfigForDevicePort(connectedPort);
+        mPatch = std::make_unique<WithAudioPatch>(IOTraits<Stream>::is_input, portConfig.value(),
+                                                  devicePortConfig);
+        ASSERT_NO_FATAL_FAILURE(mPatch->SetUp(mModule));
+    }
+
     bool mSkipTest = false;
     IModule* mModule = nullptr;
     ModuleConfig* mModuleConfig = nullptr;
@@ -4288,9 +4296,11 @@
     if (streamOut.skipTest()) {
         GTEST_SKIP() << "No mix port for attached devices";
     }
+    auto address = streamOut.getAudioDeviceAddress();
+    ASSERT_TRUE(address.has_value());
 
     // open input stream
-    WithRemoteSubmix<IStreamIn> streamIn(streamOut.getAudioDeviceAddress());
+    WithRemoteSubmix<IStreamIn> streamIn(address.value());
     ASSERT_NO_FATAL_FAILURE(streamIn.SetUp(module.get(), moduleConfig.get()));
     if (streamIn.skipTest()) {
         GTEST_SKIP() << "No mix port for attached devices";
@@ -4307,9 +4317,11 @@
     if (streamOut.skipTest()) {
         GTEST_SKIP() << "No mix port for attached devices";
     }
+    auto address = streamOut.getAudioDeviceAddress();
+    ASSERT_TRUE(address.has_value());
 
     // open input stream
-    WithRemoteSubmix<IStreamIn> streamIn(streamOut.getAudioDeviceAddress());
+    WithRemoteSubmix<IStreamIn> streamIn(address.value());
     ASSERT_NO_FATAL_FAILURE(streamIn.SetUp(module.get(), moduleConfig.get()));
     if (streamIn.skipTest()) {
         GTEST_SKIP() << "No mix port for attached devices";
@@ -4321,6 +4333,43 @@
     ASSERT_NO_FATAL_FAILURE(streamIn.sendBurstCommands());
 }
 
+TEST_P(AudioModuleRemoteSubmix, OpenInputMultipleTimes) {
+    // open output stream
+    WithRemoteSubmix<IStreamOut> streamOut;
+    ASSERT_NO_FATAL_FAILURE(streamOut.SetUp(module.get(), moduleConfig.get()));
+    if (streamOut.skipTest()) {
+        GTEST_SKIP() << "No mix port for attached devices";
+    }
+    auto address = streamOut.getAudioDeviceAddress();
+    ASSERT_TRUE(address.has_value());
+
+    // connect remote submix input device port
+    auto port = WithRemoteSubmix<IStreamIn>::getRemoteSubmixAudioPort(moduleConfig.get(),
+                                                                      address.value());
+    ASSERT_TRUE(port.has_value()) << "Device AudioPort for remote submix not found";
+    WithDevicePortConnectedState connectedInputPort(port.value());
+    ASSERT_NO_FATAL_FAILURE(connectedInputPort.SetUp(module.get(), moduleConfig.get()));
+
+    // open input streams
+    const int streamInCount = 3;
+    std::vector<std::unique_ptr<WithRemoteSubmix<IStreamIn>>> streamIns(streamInCount);
+    for (int i = 0; i < streamInCount; i++) {
+        streamIns[i] = std::make_unique<WithRemoteSubmix<IStreamIn>>();
+        ASSERT_NO_FATAL_FAILURE(
+                streamIns[i]->SetUp(module.get(), moduleConfig.get(), connectedInputPort.get()));
+        if (streamIns[i]->skipTest()) {
+            GTEST_SKIP() << "No mix port for attached devices";
+        }
+    }
+    // write something to output stream
+    ASSERT_NO_FATAL_FAILURE(streamOut.sendBurstCommands());
+
+    // read from input streams
+    for (int i = 0; i < streamInCount; i++) {
+        ASSERT_NO_FATAL_FAILURE(streamIns[i]->sendBurstCommands());
+    }
+}
+
 INSTANTIATE_TEST_SUITE_P(AudioModuleRemoteSubmixTest, AudioModuleRemoteSubmix,
                          ::testing::ValuesIn(getRemoteSubmixModuleInstance()));
 GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(AudioModuleRemoteSubmix);
diff --git a/automotive/sv/1.0/default/tests/fuzzer/AutomotiveSvV1_0Fuzzer.cpp b/automotive/sv/1.0/default/tests/fuzzer/AutomotiveSvV1_0Fuzzer.cpp
index 98834f5..4c4cc70 100644
--- a/automotive/sv/1.0/default/tests/fuzzer/AutomotiveSvV1_0Fuzzer.cpp
+++ b/automotive/sv/1.0/default/tests/fuzzer/AutomotiveSvV1_0Fuzzer.cpp
@@ -41,35 +41,32 @@
 
 void SurroundViewFuzzer::invoke2dSessionAPI() {
     sp<ISurroundView2dSession> surroundView2dSession;
+    sp<SurroundViewStream> handler;
+    mSurroundViewService->start2dSession(
+            [&surroundView2dSession](const sp<ISurroundView2dSession>& session, SvResult result) {
+                if (result == SvResult::OK) {
+                    surroundView2dSession = session;
+                }
+            });
+
+    if (surroundView2dSession && !mIs2dStreamStarted) {
+        handler = sp<SurroundViewStream>::make(surroundView2dSession);
+        if (surroundView2dSession->startStream(handler) == SvResult::OK) {
+            mIs2dStreamStarted = true;
+        }
+    }
 
     while (mFuzzedDataProvider.remaining_bytes() > 0) {
         auto surroundView2dFunc = mFuzzedDataProvider.PickValueInArray<
                 const std::function<void()>>({
                 [&]() {
-                    mSurroundViewService->start2dSession(
-                            [&surroundView2dSession](const sp<ISurroundView2dSession>& session,
-                                                     SvResult result) {
-                                if (result == SvResult::OK) {
-                                    surroundView2dSession = session;
-                                }
-                            });
-                },
-                [&]() {
-                    if (surroundView2dSession) {
-                        sp<SurroundViewStream> handler =
-                                sp<SurroundViewStream>::make(surroundView2dSession);
-                        surroundView2dSession->startStream(handler);
-                        mIs2dStreamStarted = true;
-                    }
-                },
-                [&]() {
                     if (surroundView2dSession) {
                         surroundView2dSession->get2dMappingInfo(
                                 []([[maybe_unused]] Sv2dMappingInfo info) {});
                     }
                 },
                 [&]() {
-                    if (surroundView2dSession) {
+                    if (surroundView2dSession && mIs2dStreamStarted) {
                         Sv2dConfig config;
                         config.width = mFuzzedDataProvider.ConsumeIntegralInRange<uint32_t>(
                                 kMinConfigDimension, kMaxConfigDimension);
@@ -149,8 +146,11 @@
                     }
                 },
                 [&]() {
-                    mSurroundViewService->stop2dSession(
+                    SvResult result = mSurroundViewService->stop2dSession(
                             mFuzzedDataProvider.ConsumeBool() ? surroundView2dSession : nullptr);
+                    if (result == SvResult::OK) {
+                        mIs2dStreamStarted = false;
+                    }
                 },
         });
         surroundView2dFunc();
@@ -159,31 +159,40 @@
     if (surroundView2dSession && mIs2dStreamStarted) {
         surroundView2dSession->stopStream();
     }
+
+    if (surroundView2dSession) {
+        mSurroundViewService->stop2dSession(surroundView2dSession);
+    }
 }
 
 void SurroundViewFuzzer::invoke3dSessionAPI() {
     sp<ISurroundView3dSession> surroundView3dSession;
+    sp<SurroundViewStream> handler;
+    mSurroundViewService->start3dSession(
+            [&surroundView3dSession](const sp<ISurroundView3dSession>& session, SvResult result) {
+                if (result == SvResult::OK) {
+                    surroundView3dSession = session;
+                }
+            });
+
+    const size_t numViews = mFuzzedDataProvider.ConsumeIntegralInRange<size_t>(1, kMaxViews);
+    std::vector<View3d> views(numViews);
+    for (size_t i = 0; i < numViews; ++i) {
+        views[i].viewId = mFuzzedDataProvider.ConsumeIntegral<uint32_t>();
+    }
+    surroundView3dSession->setViews(views);
+
+    if (surroundView3dSession) {
+        handler = sp<SurroundViewStream>::make(surroundView3dSession);
+
+        if (surroundView3dSession->startStream(handler) == SvResult::OK) {
+            mIs3dStreamStarted = true;
+        }
+    }
     while (mFuzzedDataProvider.remaining_bytes() > 0) {
         auto surroundView3dFunc = mFuzzedDataProvider.PickValueInArray<
                 const std::function<void()>>({
                 [&]() {
-                    mSurroundViewService->start3dSession(
-                            [&surroundView3dSession](const sp<ISurroundView3dSession>& session,
-                                                     SvResult result) {
-                                if (result == SvResult::OK) {
-                                    surroundView3dSession = session;
-                                }
-                            });
-                },
-                [&]() {
-                    if (surroundView3dSession) {
-                        sp<SurroundViewStream> handler =
-                                sp<SurroundViewStream>::make(surroundView3dSession);
-                        surroundView3dSession->startStream(handler);
-                        mIs3dStreamStarted = true;
-                    }
-                },
-                [&]() {
                     if (surroundView3dSession) {
                         const size_t numViews =
                                 mFuzzedDataProvider.ConsumeIntegralInRange<size_t>(1, kMaxViews);
@@ -195,7 +204,7 @@
                     }
                 },
                 [&]() {
-                    if (surroundView3dSession) {
+                    if (surroundView3dSession && mIs3dStreamStarted) {
                         Sv3dConfig config;
                         config.width = mFuzzedDataProvider.ConsumeIntegralInRange<uint32_t>(
                                 kMinConfigDimension, kMaxConfigDimension);
@@ -306,8 +315,11 @@
                     }
                 },
                 [&]() {
-                    mSurroundViewService->stop3dSession(
+                    SvResult result = mSurroundViewService->stop3dSession(
                             mFuzzedDataProvider.ConsumeBool() ? surroundView3dSession : nullptr);
+                    if (result == SvResult::OK) {
+                        mIs3dStreamStarted = false;
+                    }
                 },
         });
         surroundView3dFunc();
@@ -315,6 +327,10 @@
     if (surroundView3dSession && mIs3dStreamStarted) {
         surroundView3dSession->stopStream();
     }
+
+    if (surroundView3dSession) {
+        mSurroundViewService->stop3dSession(surroundView3dSession);
+    }
 }
 
 void SurroundViewFuzzer::process() {
diff --git a/automotive/vehicle/OWNERS b/automotive/vehicle/OWNERS
index 429ec39..d6969e5 100644
--- a/automotive/vehicle/OWNERS
+++ b/automotive/vehicle/OWNERS
@@ -1,3 +1,2 @@
 ericjeong@google.com
-keunyoung@google.com
 shanyu@google.com
diff --git a/media/c2/aidl/aidl_api/android.hardware.media.c2/current/android/hardware/media/c2/IGraphicBufferAllocator.aidl b/media/c2/aidl/aidl_api/android.hardware.media.c2/current/android/hardware/media/c2/IGraphicBufferAllocator.aidl
index da3d5ff..3e460dd 100644
--- a/media/c2/aidl/aidl_api/android.hardware.media.c2/current/android/hardware/media/c2/IGraphicBufferAllocator.aidl
+++ b/media/c2/aidl/aidl_api/android.hardware.media.c2/current/android/hardware/media/c2/IGraphicBufferAllocator.aidl
@@ -36,7 +36,7 @@
 interface IGraphicBufferAllocator {
   android.hardware.media.c2.IGraphicBufferAllocator.Allocation allocate(in android.hardware.media.c2.IGraphicBufferAllocator.Description desc);
   boolean deallocate(in long id);
-  android.hardware.media.c2.IGraphicBufferAllocator.WaitableFds getWaitableFds();
+  ParcelFileDescriptor getWaitableFd();
   parcelable Allocation {
     android.hardware.HardwareBuffer buffer;
     ParcelFileDescriptor fence;
@@ -47,8 +47,4 @@
     int format;
     long usage;
   }
-  parcelable WaitableFds {
-    ParcelFileDescriptor allocEvent;
-    ParcelFileDescriptor statusEvent;
-  }
 }
diff --git a/media/c2/aidl/android/hardware/media/c2/IGraphicBufferAllocator.aidl b/media/c2/aidl/android/hardware/media/c2/IGraphicBufferAllocator.aidl
index 1c97214..49c4ea4 100644
--- a/media/c2/aidl/android/hardware/media/c2/IGraphicBufferAllocator.aidl
+++ b/media/c2/aidl/android/hardware/media/c2/IGraphicBufferAllocator.aidl
@@ -75,31 +75,22 @@
     boolean deallocate(in long id);
 
     /**
-     * Fds for waitable object events.
-     *
-     * Fds are created by eventfd() with semaphore mode.
-     * For allocEvent, An integer counter regarding dequeuable buffer count is maintained
-     * by client using read()/write() to the fd. The fd can be checked whether it is
-     * readable via poll(). When in readable status, the specified counter is positive
-     * so allocate/dequeue can happen.
-     *
-     * For statusEvent, the client can notify further allocation is not feasible.
-     * e.g.) life-cycle of the underlying allocator is ended.
-     *
-     * C2Fence object should be implemented based on this Fds. Thus, C2Fence can return
-     * either by allocation being ready or allocation being infeasible by the client status
-     * change.
-     */
-    parcelable WaitableFds {
-        ParcelFileDescriptor allocEvent;
-        ParcelFileDescriptor statusEvent;
-    }
-
-    /**
-     * Gets waiable file descriptors.
+     * Gets a waitable file descriptor.
      *
      * Use this method once and cache it in order not to create unnecessary duplicated fds.
-     * The returned array will have two fds.
+     *
+     * Two file descriptors are created by pipe2(), and the reading end will be returned
+     * and shared by this method. Whenever a dequeuable buffer is ready a byte will be
+     * written to the writing end. Whenever a buffer is allocated(or dequeued) a byte will
+     * be read from the reading end.
+     *
+     * The returned file descriptor(the reading end) can be polled whether the read is ready
+     * via ::poll(). If no more allocate() can be fulfilled(by status change or etc.), the
+     * writing end will be closed. In the case, POLLHUP event can be retrieved via ::poll().
+     *
+     * C2Fence object should be implemented based on this Fd. Thus, C2Fence can return
+     * either by allocation being ready or allocation being infeasible by the client status
+     * change.
      *
      * If many waitable objects based on the same fd are competing, all watiable objects will be
      * notified. After being notified, they should invoke allocate(). At least one of them can
@@ -110,5 +101,5 @@
      * @return an fd array which will be wrapped to C2Fence and will be waited for
      *     until allocating is unblocked.
      */
-    WaitableFds getWaitableFds();
+    ParcelFileDescriptor getWaitableFd();
 }