rsx: recover from FIFO parse errors

- Validate FIFO registers before access

-- Validate the args ptr separate from the get ptr

rpcs3/Emu/RSX/RSXThread.cpp

@@ -403,6 +403,19 @@ namespace rsx
 				continue;
 			}
 
+			//Validate put and get registers
+			//TODO: Who should handle graphics exceptions??
+			const u32 get_address = RSXIOMem.RealAddr(get);
+			
+			if (!get_address)
+			{
+				LOG_ERROR(RSX, "Invalid FIFO queue get/put registers found, get=0x%X, put=0x%X", get, put);
+
+				invalid_command_interrupt_raised = true;
+				ctrl->get = put;
+				continue;
+			}
+
 			const u32 cmd = ReadIO32(get);
 			const u32 count = (cmd >> 18) & 0x7ff;
 
@@ -442,7 +455,20 @@ namespace rsx
 				continue;
 			}
 
-			auto args = vm::ptr<u32>::make((u32)RSXIOMem.RealAddr(get + 4));
+			//Validate the args ptr if the command attempts to read from it
+			const u32 args_address = RSXIOMem.RealAddr(get + 4);
+
+			if (!args_address && count)
+			{
+				LOG_ERROR(RSX, "Invalid FIFO queue args ptr found, get=0x%X, cmd=0x%X, count=%d", get, cmd, count);
+
+				invalid_command_interrupt_raised = true;
+				ctrl->get = put;
+				continue;
+			}
+
+			auto args = vm::ptr<u32>::make(args_address);
+			invalid_command_interrupt_raised = false;
 
 			u32 first_cmd = (cmd & 0xfffc) >> 2;
 
@@ -469,7 +495,17 @@ namespace rsx
 				{
 					method(this, reg, value);
 				}
+
+				if (invalid_command_interrupt_raised)
+				{
+					//Ignore processing the rest of the chain
+					ctrl->get = put;
+					break;
 				}
+			}
+
+			if (invalid_command_interrupt_raised)
+				continue;
 
 			ctrl->get = get + (count + 1) * 4;
 		}

rpcs3/Emu/RSX/RSXThread.h

@@ -232,6 +232,7 @@ namespace rsx
 
 	public:
 		std::set<u32> m_used_gcm_commands;
+		bool invalid_command_interrupt_raised = false;
 
 	protected:
 		thread();

rpcs3/Emu/RSX/gcm_enums.h

@@ -1000,7 +1000,12 @@ enum
 	NV3089_IMAGE_IN_OFFSET = 0x0000C408 >> 2,
 	NV3089_IMAGE_IN = 0x0000C40C >> 2,
 
+	GCM_FLIP_HEAD0 = 0X0000E920 >> 2,
+	GCM_FLIP_HEAD1 = 0X0000E924 >> 2,
+	GCM_PREPARE_DISPLAY_BUFFER_HEAD0 = 0X0000E940 >> 2,	//0X940 + [HEAD << 2]
+	GCM_PREPARE_DISPLAY_BUFFER_HEAD1 = 0X0000E944 >> 2,
 	GCM_SET_USER_COMMAND = 0x0000EB00 >> 2,
+	GCM_SET_USER_COMMAND2 = 0x0000EB04 >> 2,
 
 	GCM_FLIP_COMMAND = 0x0000FEAC >> 2
 };

rpcs3/Emu/RSX/rsx_methods.cpp

@@ -29,9 +29,12 @@ namespace rsx
 	
 	std::array<rsx_method_t, 0x10000 / 4> methods{};
 
-	[[noreturn]] void invalid_method(thread*, u32 _reg, u32 arg)
+	void invalid_method(thread* rsx, u32 _reg, u32 arg)
 	{
-		fmt::throw_exception("Invalid RSX method 0x%x (arg=0x%x)" HERE, _reg << 2, arg);
+		//Don't throw, gather information and ignore broken/garbage commands
+		//TODO: Investigate why these commands are executed at all. (Heap corruption? Alignment padding?)
+		LOG_ERROR(RSX, "Invalid RSX method 0x%x (arg=0x%x)" HERE, _reg << 2, arg);
+		rsx->invalid_command_interrupt_raised = true;
 	}
 
 	template<typename Type> struct vertex_data_type_from_element_type;
@@ -1244,6 +1247,10 @@ namespace rsx
 		methods[NV3089_IMAGE_IN_OFFSET]                   = nullptr;
 		methods[NV3089_IMAGE_IN]                          = nullptr;
 
+		//Some custom GCM methods
+		methods[GCM_PREPARE_DISPLAY_BUFFER_HEAD0]         = nullptr;
+		methods[GCM_PREPARE_DISPLAY_BUFFER_HEAD1]         = nullptr;
+
 		bind_array<NV4097_SET_ANISO_SPREAD, 1, 16, nullptr>();
 		bind_array<NV4097_SET_VERTEX_TEXTURE_OFFSET, 1, 8 * 4, nullptr>();
 		bind_array<NV4097_SET_VERTEX_DATA_SCALED4S_M, 1, 32, nullptr>();
@@ -1333,7 +1340,10 @@ namespace rsx
 
 		// custom methods
 		bind<GCM_FLIP_COMMAND, flip_command>();
+		bind<GCM_FLIP_HEAD0, flip_command>();
+		bind<GCM_FLIP_HEAD1, flip_command>();
 		bind<GCM_SET_USER_COMMAND, user_command>();
+		bind<GCM_SET_USER_COMMAND2, user_command>();
 
 		return true;	
 	}();