Thread safe enq_reply.

Source/Core/Core/Src/IPC_HLE/WII_IPC_HLE.cpp

@@ -83,6 +83,7 @@ IWII_IPC_HLE_Device* es_handles[ES_MAX_COUNT];
 typedef std::deque<u32> ipc_msg_queue;
 static ipc_msg_queue request_queue;	// ppc -> arm
 static ipc_msg_queue reply_queue;	// arm -> ppc
+static std::mutex s_reply_queue;
 
 void Init()
 {
@@ -159,7 +160,12 @@ void Reset(bool _bHard)
 		g_DeviceMap.erase(g_DeviceMap.begin(), g_DeviceMap.end());
 	}
 	request_queue.clear();
-	reply_queue.clear();
+
+	// lock due to using reply_queue
+	{
+		std::lock_guard<std::mutex> lk(s_reply_queue);
+		reply_queue.clear();
+	}
 }
 
 void Shutdown()
@@ -241,6 +247,8 @@ IWII_IPC_HLE_Device* CreateFileIO(u32 _DeviceID, const std::string& _rDeviceName
 
 void DoState(PointerWrap &p)
 {
+	std::lock_guard<std::mutex> lk(s_reply_queue);
+
 	p.Do(request_queue);
 	p.Do(reply_queue);
 
@@ -536,6 +544,7 @@ void EnqRequest(u32 _Address)
 // Called when IOS module has some reply
 void EnqReply(u32 _Address)
 {
+	std::lock_guard<std::mutex> lk(s_reply_queue);
 	reply_queue.push_back(_Address);
 }
 
@@ -560,12 +569,16 @@ void Update()
 		Dolphin_Debugger::PrintCallstack(LogTypes::WII_IPC_HLE, LogTypes::LDEBUG);
 #endif
 	}
-
-	if (reply_queue.size())
+	
+	// lock due to using reply_queue
 	{
-		WII_IPCInterface::GenerateReply(reply_queue.front());
-		INFO_LOG(WII_IPC_HLE, "<<-- Reply to IPC Request @ 0x%08x", reply_queue.front());
-		reply_queue.pop_front();
+		std::lock_guard<std::mutex> lk(s_reply_queue);
+		if (reply_queue.size())
+		{
+			WII_IPCInterface::GenerateReply(reply_queue.front());
+			INFO_LOG(WII_IPC_HLE, "<<-- Reply to IPC Request @ 0x%08x", reply_queue.front());
+			reply_queue.pop_front();
+		}
 	}
 }