There is a racing between SyncSocket::Receive in audio_thread_ and SyncSocket::Close in renderer ...

content/renderer/media/audio_device.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // Low-latency audio rendering unit utilizing audio output stream provided
 // by browser process through IPC.
 //
 // Relationship of classes.
 //
 //  AudioOutputController                AudioDevice
@@ skipping 70 matching lines @@
   // Methods called on main render thread -------------------------------------
   AudioDevice(size_t buffer_size,
               int channels,
               double sample_rate,
               RenderCallback* callback);
   virtual ~AudioDevice();
 
   // Starts audio playback.
   void Start();
 
-  // Stops audio playback. Returns |true| on success.
-  bool Stop();
+  // Stops audio playback.
+  void Stop();
 
   // Sets the playback volume, with range [0.0, 1.0] inclusive.
   // Returns |true| on success.
   bool SetVolume(double volume);
 
   // Gets the playback volume, with range [0.0, 1.0] inclusive.
   void GetVolume(double* volume);
 
   double sample_rate() const { return sample_rate_; }
   size_t buffer_size() const { return buffer_size_; }
@@ skipping 17 matching lines @@
   void InitializeOnIOThread(const AudioParameters& params);
   void StartOnIOThread();
   void ShutDownOnIOThread(base::WaitableEvent* completion);
   void SetVolumeOnIOThread(double volume);
 
   void Send(IPC::Message* message);
 
   // Method called on the audio thread (+ one call on the IO thread) ----------
   // Calls the client's callback for rendering audio. There will also be one
   // initial call on the IO thread before the audio thread has been created.
-  void FireRenderCallback();
+  void FireRenderCallback(int16* data);
 
   // DelegateSimpleThread::Delegate implementation.
   virtual void Run() OVERRIDE;
 
   // Format
   size_t buffer_size_;  // in sample-frames
   int channels_;
   int bits_per_sample_;
   double sample_rate_;
 
   RenderCallback* callback_;
 
   // The client callback renders audio into here.
   std::vector<float*> audio_data_;
 
   // The client stores the last reported audio delay in this member.
   // The delay shall reflect the amount of audio which still resides in
   // the output buffer, i.e., the expected audio output delay.
   int audio_delay_milliseconds_;
 
   // The current volume scaling [0.0, 1.0] of the audio stream.
   double volume_;
 
   // Callbacks for rendering audio occur on this thread.
   scoped_ptr<base::DelegateSimpleThread> audio_thread_;
 
-  // IPC message stuff.
-  base::SharedMemory* shared_memory() { return shared_memory_.get(); }
-  base::SyncSocket* socket() { return socket_.get(); }
-  void* shared_memory_data() { return shared_memory()->memory(); }
-
   // Cached audio message filter (lives on the main render thread).
   scoped_refptr<AudioMessageFilter> filter_;
 
   // Our stream ID on the message filter. Only accessed on the IO thread.
   int32 stream_id_;
 
   // Data transfer between browser and render process uses a combination
   // of sync sockets and shared memory to provide lowest possible latency.
-  scoped_ptr<base::SharedMemory> shared_memory_;
-  scoped_ptr<base::SyncSocket> socket_;
+  base::SharedMemoryHandle shared_memory_handle_;
+  base::SyncSocket::Handle socket_handle_;
+  int memory_length_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(AudioDevice);
 };
 
 #endif  // CONTENT_RENDERER_MEDIA_AUDIO_DEVICE_H_