diff --git a/sdk/xtdk/amd64/ketypes.h b/sdk/xtdk/amd64/ketypes.h
index 4ff38f7..c177871 100644
--- a/sdk/xtdk/amd64/ketypes.h
+++ b/sdk/xtdk/amd64/ketypes.h
@@ -9,12 +9,19 @@
 #ifndef __XTDK_AMD64_KETYPES_H
 #define __XTDK_AMD64_KETYPES_H
 
+#include <xtbase.h>
 #include <xttypes.h>
 
 
+/* Size of the exception area */
+#define EXCEPTION_AREA_SIZE               64
+
 /* IOPM Definitions */
 #define IO_ACCESS_MAP_NONE                0
 
+/* Size of the FNSAVE/FRSTOR save area */
+#define FLOATING_SAVE_AREA_SIZE           ((sizeof(FLOATING_SAVE_AREA) + 15) & ~15)
+
 /* Static Kernel-Mode address start */
 #define KSEG0_BASE                        0xFFFFF80000000000
 
@@ -24,6 +31,104 @@
 /* XTOS Kernel stack size */
 #define KERNEL_STACK_SIZE                 0x8000
 
+/* Kernel frames */
+#define KEXCEPTION_FRAME_SIZE             sizeof(KEXCEPTION_FRAME)
+#define KSWITCH_FRAME_SIZE                sizeof(KSWITCH_FRAME)
+#define KTRAP_FRAME_ALIGN                 0x10
+#define KTRAP_FRAME_SIZE                  sizeof(KTRAP_FRAME)
+
+/* Size of legacy 387 registers */
+#define SIZE_OF_80387_REGISTERS           80
+
+/* Floating point state storing structure */
+typedef struct _FLOATING_SAVE_AREA
+{
+    USHORT ControlWord;
+    USHORT StatusWord;
+    USHORT TagWord;
+    ULONG ErrorOffset;
+    USHORT ErrorSelector;
+    USHORT ErrorOpcode;
+    ULONG DataOffset;
+    USHORT DataSelector;
+    UCHAR RegisterArea[SIZE_OF_80387_REGISTERS];
+} FLOATING_SAVE_AREA, *PFLOATING_SAVE_AREA;
+
+/* Context frame structure definition */
+typedef struct ALIGN(16) _CONTEXT
+{
+    ULONG64 P1Home;
+    ULONG64 P2Home;
+    ULONG64 P3Home;
+    ULONG64 P4Home;
+    ULONG64 P5Home;
+    ULONG64 P6Home;
+    ULONG ContextFlags;
+    ULONG MxCsr;
+    USHORT SegCs;
+    USHORT SegDs;
+    USHORT SegEs;
+    USHORT SegFs;
+    USHORT SegGs;
+    USHORT SegSs;
+    ULONG EFlags;
+    ULONG64 Dr0;
+    ULONG64 Dr1;
+    ULONG64 Dr2;
+    ULONG64 Dr3;
+    ULONG64 Dr6;
+    ULONG64 Dr7;
+    ULONG64 Rax;
+    ULONG64 Rcx;
+    ULONG64 Rdx;
+    ULONG64 Rbx;
+    ULONG64 Rsp;
+    ULONG64 Rbp;
+    ULONG64 Rsi;
+    ULONG64 Rdi;
+    ULONG64 R8;
+    ULONG64 R9;
+    ULONG64 R10;
+    ULONG64 R11;
+    ULONG64 R12;
+    ULONG64 R13;
+    ULONG64 R14;
+    ULONG64 R15;
+    ULONG64 Rip;
+    union
+    {
+        FLOATING_SAVE_AREA FloatSave;
+        struct
+        {
+            M128 Header[2];
+            M128 Legacy[8];
+            M128 Xmm0;
+            M128 Xmm1;
+            M128 Xmm2;
+            M128 Xmm3;
+            M128 Xmm4;
+            M128 Xmm5;
+            M128 Xmm6;
+            M128 Xmm7;
+            M128 Xmm8;
+            M128 Xmm9;
+            M128 Xmm10;
+            M128 Xmm11;
+            M128 Xmm12;
+            M128 Xmm13;
+            M128 Xmm14;
+            M128 Xmm15;
+        };
+    };
+    M128 VectorRegister[26];
+    ULONG64 VectorControl;
+    ULONG64 DebugControl;
+    ULONG64 LastBranchToRip;
+    ULONG64 LastBranchFromRip;
+    ULONG64 LastExceptionToRip;
+    ULONG64 LastExceptionFromRip;
+} CONTEXT, *PCONTEXT;
+
 /* Global Descriptor Table (GDT) entry union definition */
 typedef union _KGDTENTRY
 {
@@ -91,4 +196,142 @@ typedef struct _KTSS
     USHORT IoMapBase;
 } KTSS, *PKTSS;
 
+/* Exception frame definition */
+typedef struct _KEXCEPTION_FRAME
+{
+    ULONG64 P1Home;
+    ULONG64 P2Home;
+    ULONG64 P3Home;
+    ULONG64 P4Home;
+    ULONG64 P5;
+    ULONG64 InitialStack;
+    M128 Xmm6;
+    M128 Xmm7;
+    M128 Xmm8;
+    M128 Xmm9;
+    M128 Xmm10;
+    M128 Xmm11;
+    M128 Xmm12;
+    M128 Xmm13;
+    M128 Xmm14;
+    M128 Xmm15;
+    ULONG64 TrapFrame;
+    ULONG64 CallbackStack;
+    ULONG64 OutputBuffer;
+    ULONG64 OutputLength;
+    UCHAR ExceptionRecord[EXCEPTION_AREA_SIZE];
+    ULONG64 MxCsr;
+    ULONG64 Rbp;
+    ULONG64 Rbx;
+    ULONG64 Rdi;
+    ULONG64 Rsi;
+    ULONG64 R12;
+    ULONG64 R13;
+    ULONG64 R14;
+    ULONG64 R15;
+    ULONG64 Return;
+} KEXCEPTION_FRAME, *PKEXCEPTION_FRAME;
+
+/* Switch frame definition */
+typedef struct _KSWITCH_FRAME
+{
+    ULONG64 P1Home;
+    ULONG64 P2Home;
+    ULONG64 P3Home;
+    ULONG64 P4Home;
+    ULONG64 P5Home;
+    ULONG MxCsr;
+    KIRQL ApcBypass;
+    UCHAR Fill1[3];
+    ULONG64 Rbp;
+    ULONG64 Return;
+} KSWITCH_FRAME, *PKSWITCH_FRAME;
+
+/* Trap frame definition */
+typedef struct _KTRAP_FRAME
+{
+    ULONG64 P1Home;
+    ULONG64 P2Home;
+    ULONG64 P3Home;
+    ULONG64 P4Home;
+    ULONG64 P5;
+    KPROCESSOR_MODE PreviousMode;
+    KIRQL PreviousIrql;
+    UCHAR FaultIndicator;
+    UCHAR ExceptionActive;
+    ULONG MxCsr;
+    ULONG64 Rax;
+    ULONG64 Rcx;
+    ULONG64 Rdx;
+    ULONG64 R8;
+    ULONG64 R9;
+    ULONG64 R10;
+    ULONG64 R11;
+    union
+    {
+        ULONG64 GsBase;
+        ULONG64 GsSwap;
+    };
+    M128 Xmm0;
+    M128 Xmm1;
+    M128 Xmm2;
+    M128 Xmm3;
+    M128 Xmm4;
+    M128 Xmm5;
+    union
+    {
+        ULONG64 FaultAddress;
+        ULONG64 ContextRecord;
+        ULONG64 TimeStampCKCL;
+    };
+    ULONG64 Dr0;
+    ULONG64 Dr1;
+    ULONG64 Dr2;
+    ULONG64 Dr3;
+    ULONG64 Dr6;
+    ULONG64 Dr7;
+    union
+    {
+        struct
+        {
+            ULONG64 DebugControl;
+            ULONG64 LastBranchToRip;
+            ULONG64 LastBranchFromRip;
+            ULONG64 LastExceptionToRip;
+            ULONG64 LastExceptionFromRip;
+        };
+        struct
+        {
+            ULONG64 LastBranchControl;
+            ULONG LastBranchMSR;
+        };
+    };
+    USHORT SegDs;
+    USHORT SegEs;
+    USHORT SegFs;
+    USHORT SegGs;
+    ULONG64 TrapFrame;
+    ULONG64 Rbx;
+    ULONG64 Rdi;
+    ULONG64 Rsi;
+    ULONG64 Rbp;
+    union
+    {
+        ULONG64 ErrorCode;
+        ULONG64 ExceptionFrame;
+        ULONG64 TimeStampKlog;
+    };
+    ULONG64 Rip;
+    USHORT SegCs;
+    UCHAR Fill0;
+    UCHAR Logging;
+    USHORT Fill1[2];
+    ULONG EFlags;
+    ULONG Fill2;
+    ULONG64 Rsp;
+    USHORT SegSs;
+    USHORT Fill3;
+    ULONG CodePatchCycle;
+} KTRAP_FRAME, *PKTRAP_FRAME;
+
 #endif /* __XTDK_AMD64_KETYPES_H */
diff --git a/sdk/xtdk/amd64/xtstruct.h b/sdk/xtdk/amd64/xtstruct.h
index 0998f92..9d18943 100644
--- a/sdk/xtdk/amd64/xtstruct.h
+++ b/sdk/xtdk/amd64/xtstruct.h
@@ -9,10 +9,21 @@
 #ifndef __XTDK_AMD64_XTSTRUCT_H
 #define __XTDK_AMD64_XTSTRUCT_H
 
+#include <xtdefs.h>
+
+
+/* Architecture-related enumeration lists forward references */
+typedef enum _CPUID_FEATURES CPUID_FEATURES, *PCPUID_FEATURES;
+typedef enum _CPUID_REQUESTS CPUID_REQUESTS, *PCPUID_REQUESTS;
 
 /* Architecture-related structures forward references */
+typedef struct ALIGN(16) _CONTEXT CONTEXT, *PCONTEXT;
 typedef struct _CPUID_REGISTERS CPUID_REGISTERS, *PCPUID_REGISTERS;
+typedef struct _FLOATING_SAVE_AREA FLOATING_SAVE_AREA, *PFLOATING_SAVE_AREA;
 typedef struct _HARDWARE_PTE HARDWARE_PTE, *PHARDWARE_PTE;
+typedef struct _KEXCEPTION_FRAME KEXCEPTION_FRAME, *PKEXCEPTION_FRAME;
+typedef struct _KSWITCH_FRAME KSWITCH_FRAME, *PKSWITCH_FRAME;
+typedef struct _KTRAP_FRAME KTRAP_FRAME, *PKTRAP_FRAME;
 typedef struct _KTSS KTSS, *PKTSS;
 
 /* Architecture-related unions forward references */
diff --git a/sdk/xtdk/i686/ketypes.h b/sdk/xtdk/i686/ketypes.h
index ad503c4..5192f6f 100644
--- a/sdk/xtdk/i686/ketypes.h
+++ b/sdk/xtdk/i686/ketypes.h
@@ -9,6 +9,7 @@
 #ifndef __XTDK_I686_KETYPES_H
 #define __XTDK_I686_KETYPES_H
 
+#include <xtstruct.h>
 #include <xttypes.h>
 
 
@@ -28,6 +29,61 @@
 /* XTOS Kernel stack size */
 #define KERNEL_STACK_SIZE                 0x4000
 
+/* Kernel frames */
+#define KTRAP_FRAME_ALIGN                 0x08
+#define KTRAP_FRAME_SIZE                  sizeof(KTRAP_FRAME)
+#define NPX_FRAME_SIZE                    0x210
+
+/* Number of supported extensions */
+#define MAXIMUM_SUPPORTED_EXTENSION       512
+
+/* Size of 387 registers */
+#define SIZE_OF_80387_REGISTERS           80
+
+/* Floating point state storing structure */
+typedef struct _FLOATING_SAVE_AREA
+{
+    ULONG ControlWord;
+    ULONG StatusWord;
+    ULONG TagWord;
+    ULONG ErrorOffset;
+    ULONG ErrorSelector;
+    ULONG DataOffset;
+    ULONG DataSelector;
+    UCHAR RegisterArea[SIZE_OF_80387_REGISTERS];
+    ULONG Cr0NpxState;
+} FLOATING_SAVE_AREA, *PFLOATING_SAVE_AREA;
+
+/* Context frame structure definition */
+typedef struct _CONTEXT
+{
+    ULONG ContextFlags;
+    ULONG Dr0;
+    ULONG Dr1;
+    ULONG Dr2;
+    ULONG Dr3;
+    ULONG Dr6;
+    ULONG Dr7;
+    FLOATING_SAVE_AREA FloatSave;
+    ULONG SegGs;
+    ULONG SegFs;
+    ULONG SegEs;
+    ULONG SegDs;
+    ULONG Edi;
+    ULONG Esi;
+    ULONG Ebx;
+    ULONG Edx;
+    ULONG Ecx;
+    ULONG Eax;
+    ULONG Ebp;
+    ULONG Eip;
+    ULONG SegCs;
+    ULONG EFlags;
+    ULONG Esp;
+    ULONG SegSs;
+    UCHAR ExtendedRegisters[MAXIMUM_SUPPORTED_EXTENSION];
+} CONTEXT, *PCONTEXT;
+
 /* Global Descriptor Table (GDT) entry structure definition */
 typedef struct _KGDTENTRY
 {
@@ -59,7 +115,8 @@ typedef struct _KGDTENTRY
 } KGDTENTRY, *PKGDTENTRY;
 
 /* Interrupt Descriptor Table (IDT) entry structure definition */
-typedef struct _KIDTENTRY {
+typedef struct _KIDTENTRY
+{
     USHORT Offset;
     USHORT Selector;
     USHORT Access;
@@ -67,13 +124,15 @@ typedef struct _KIDTENTRY {
 } KIDTENTRY, *PKIDTENTRY;
 
 /* Interrupt direction access map structure definition */
-typedef struct _KIIO_ACCESS_MAP {
+typedef struct _KIIO_ACCESS_MAP
+{
     UCHAR DirectionMap[IOPM_DIRECTION_MAP_SIZE];
     UCHAR IoMap[IOPM_FULL_SIZE];
 } KIIO_ACCESS_MAP, *PKIIO_ACCESS_MAP;
 
 /* Task State Segment (TSS) structure definition */
-typedef struct _KTSS {
+typedef struct _KTSS
+{
     USHORT Backlink;
     USHORT Reserved0;
     ULONG Esp0;
@@ -111,4 +170,50 @@ typedef struct _KTSS {
     UCHAR IntDirectionMap[IOPM_DIRECTION_MAP_SIZE];
 } KTSS, *PKTSS;
 
+/* Exception frame definition (not available on ia32) */
+typedef struct _KEXCEPTION_FRAME
+{
+    ULONG PlaceHolder;
+} KEXCEPTION_FRAME, *PKEXCEPTION_FRAME;
+
+/* Trap frame definition */
+typedef struct _KTRAP_FRAME
+{
+    ULONG DbgEbp;
+    ULONG DbgEip;
+    ULONG DbgArgMark;
+    ULONG DbgArgPointer;
+    ULONG TempSegCs;
+    ULONG TempEsp;
+    ULONG Dr0;
+    ULONG Dr1;
+    ULONG Dr2;
+    ULONG Dr3;
+    ULONG Dr6;
+    ULONG Dr7;
+    ULONG SegGs;
+    ULONG SegEs;
+    ULONG SegDs;
+    ULONG Edx;
+    ULONG Ecx;
+    ULONG Eax;
+    ULONG PreviousPreviousMode;
+    PEXCEPTION_REGISTRATION_RECORD ExceptionList;
+    ULONG SegFs;
+    ULONG Edi;
+    ULONG Esi;
+    ULONG Ebx;
+    ULONG Ebp;
+    ULONG ErrCode;
+    ULONG Eip;
+    ULONG SegCs;
+    ULONG EFlags;
+    ULONG HardwareEsp;
+    ULONG HardwareSegSs;
+    ULONG V86Es;
+    ULONG V86Ds;
+    ULONG V86Fs;
+    ULONG V86Gs;
+} KTRAP_FRAME, *PKTRAP_FRAME;
+
 #endif /* __XTDK_I686_KETYPES_H */
diff --git a/sdk/xtdk/i686/xtstruct.h b/sdk/xtdk/i686/xtstruct.h
index 5cd8f9a..a87be3b 100644
--- a/sdk/xtdk/i686/xtstruct.h
+++ b/sdk/xtdk/i686/xtstruct.h
@@ -9,14 +9,24 @@
 #ifndef __XTDK_I686_XTSTRUCT_H
 #define __XTDK_I686_XTSTRUCT_H
 
+#include <xtdefs.h>
+
+
+/* Architecture-related enumeration lists forward references */
+typedef enum _CPUID_FEATURES CPUID_FEATURES, *PCPUID_FEATURES;
+typedef enum _CPUID_REQUESTS CPUID_REQUESTS, *PCPUID_REQUESTS;
 
 /* Architecture-related structures forward references */
+typedef struct _CONTEXT CONTEXT, *PCONTEXT;
 typedef struct _CPUID_REGISTERS CPUID_REGISTERS, *PCPUID_REGISTERS;
+typedef struct _FLOATING_SAVE_AREA FLOATING_SAVE_AREA, *PFLOATING_SAVE_AREA;
 typedef struct _HARDWARE_PTE HARDWARE_PTE, *PHARDWARE_PTE;
 typedef struct _HARDWARE_PTE_PAE HARDWARE_PTE_PAE, *PHARDWARE_PTE_PAE;
+typedef struct _KEXCEPTION_FRAME KEXCEPTION_FRAME, *PKEXCEPTION_FRAME;
 typedef struct _KGDTENTRY KGDTENTRY, *PKGDTENTRY;
 typedef struct _KIDTENTRY KIDTENTRY, *PKIDTENTRY;
 typedef struct _KIIO_ACCESS_MAP KIIO_ACCESS_MAP, *PKIIO_ACCESS_MAP;
+typedef struct _KTRAP_FRAME KTRAP_FRAME, *PKTRAP_FRAME;
 typedef struct _KTSS KTSS, *PKTSS;
 
 #endif /* __XTDK_I686_XTSTRUCT_H */
diff --git a/sdk/xtdk/kertptr.h b/sdk/xtdk/kertptr.h
new file mode 100644
index 0000000..546d838
--- /dev/null
+++ b/sdk/xtdk/kertptr.h
@@ -0,0 +1,21 @@
+/**
+ * PROJECT:         ExectOS
+ * COPYRIGHT:       See COPYING.md in the top level directory
+ * FILE:            sdk/xtdk/kertptr.h
+ * DESCRIPTION:     XT kernel core handlers and routine pointers
+ * DEVELOPERS:      Rafal Kupiec <belliash@codingworkshop.eu.org>
+ */
+
+#ifndef __XTDK_KERTPTR_H
+#define __XTDK_KERTPTR_H
+
+#include <xtstruct.h>
+#include <xttarget.h>
+#include <xttypes.h>
+#include ARCH_HEADER(ketypes.h)
+
+
+/* Kernel routine callbacks */
+typedef EXCEPTION_DISPOSITION (*PEXCEPTION_ROUTINE)(IN PEXCEPTION_RECORD ExceptionRecord, IN PVOID EstablisherFrame, IN OUT PCONTEXT ContextRecord, IN OUT PVOID DispatcherContext);
+
+#endif /* __XTDK_KERTPTR_H */
diff --git a/sdk/xtdk/ketypes.h b/sdk/xtdk/ketypes.h
new file mode 100644
index 0000000..4e4175a
--- /dev/null
+++ b/sdk/xtdk/ketypes.h
@@ -0,0 +1,48 @@
+/**
+ * PROJECT:         ExectOS
+ * COPYRIGHT:       See COPYING.md in the top level directory
+ * FILE:            sdk/xtdk/ketypes.h
+ * DESCRIPTION:     XT kernel core structures definitions
+ * DEVELOPERS:      Rafal Kupiec <belliash@codingworkshop.eu.org>
+ */
+
+#ifndef __XTDK_KETYPES_H
+#define __XTDK_KETYPES_H
+
+#include <kertptr.h>
+#include <xtstruct.h>
+#include <xttarget.h>
+#include <xttypes.h>
+
+
+/* Maximum number of exception parameters */
+#define EXCEPTION_MAXIMUM_PARAMETERS 15
+
+/* Exception disposition return values */
+typedef enum _EXCEPTION_DISPOSITION
+{
+    ExceptionContinueExecution,
+    ExceptionContinueSearch,
+    ExceptionNestedException,
+    ExceptionCollidedUnwind,
+} EXCEPTION_DISPOSITION, *PEXCEPTION_DISPOSITION;
+
+/* Exception record structure definition */
+typedef struct _EXCEPTION_RECORD
+{
+    XTSTATUS ExceptionCode;
+    ULONG ExceptionFlags;
+    PEXCEPTION_RECORD ExceptionRecord;
+    PVOID ExceptionAddress;
+    ULONG NumberParameters;
+    ULONG_PTR ExceptionInformation[EXCEPTION_MAXIMUM_PARAMETERS];
+} EXCEPTION_RECORD, *PEXCEPTION_RECORD;
+
+/* Exception registration record  structure definition */
+typedef struct _EXCEPTION_REGISTRATION_RECORD
+{
+  PEXCEPTION_REGISTRATION_RECORD Next;
+  PEXCEPTION_ROUTINE Handler;
+} EXCEPTION_REGISTRATION_RECORD, *PEXCEPTION_REGISTRATION_RECORD;
+
+#endif /* __XTDK_KEFUNCS_H */
diff --git a/sdk/xtdk/xtbase.h b/sdk/xtdk/xtbase.h
index 2164546..429edfc 100644
--- a/sdk/xtdk/xtbase.h
+++ b/sdk/xtdk/xtbase.h
@@ -17,6 +17,9 @@
 /* Interrupt Request Level (IRQL) */
 typedef UCHAR KIRQL, *PKIRQL;
 
+/* Processor modes */
+typedef CHAR KPROCESSOR_MODE, *PKPROCESSOR_MODE;
+
 /* 128-bit buffer containing a unique identifier value */
 typedef struct _GUID
 {
diff --git a/sdk/xtdk/xtkmapi.h b/sdk/xtdk/xtkmapi.h
index 72d06e4..312c89a 100644
--- a/sdk/xtdk/xtkmapi.h
+++ b/sdk/xtdk/xtkmapi.h
@@ -7,10 +7,10 @@
  */
 
 /* Base XT headers */
-#include <xttarget.h>
-#include <xttypes.h>
 #include <xtdefs.h>
 #include <xtstatus.h>
+#include <xttarget.h>
+#include <xttypes.h>
 
 /* XT forward references */
 #include <xtstruct.h>
@@ -21,15 +21,16 @@
 /* Architecture-independent XT API */
 #include <xtbase.h>
 #include <xtdebug.h>
+#include <xtfw.h>
 #include <xtimage.h>
 #include <xtuefi.h>
-#include <xtfw.h>
 
 /* Low level data types headers */
-#include <rtltypes.h>
-#include <ldrtypes.h>
 #include <hltypes.h>
 #include <iotypes.h>
+#include <ketypes.h>
+#include <ldrtypes.h>
+#include <rtltypes.h>
 
 /* Architecture-specific low level data types headers */
 #include ARCH_HEADER(hltypes.h)
@@ -43,3 +44,6 @@
 
 /* Architecture specific XT routines*/
 #include ARCH_HEADER(hlfuncs.h)
+
+/* Callbacks */
+#include <kertptr.h>
diff --git a/sdk/xtdk/xtstruct.h b/sdk/xtdk/xtstruct.h
index 284db94..b1b4973 100644
--- a/sdk/xtdk/xtstruct.h
+++ b/sdk/xtdk/xtstruct.h
@@ -12,6 +12,9 @@
 #include <xtdefs.h>
 
 
+/* Enumeration lists forward references */
+typedef enum _EXCEPTION_DISPOSITION EXCEPTION_DISPOSITION, *PEXCEPTION_DISPOSITION;
+
 /* Structures forward references */
 typedef struct _CPPORT CPPORT, *PCPPORT;
 typedef struct _EFI_1394_DEVICE_PATH EFI_1394_DEVICE_PATH, *PEFI_1394_DEVICE_PATH;
@@ -148,6 +151,8 @@ typedef struct _EFI_USB_DEVICE_PATH EFI_USB_DEVICE_PATH, *PEFI_USB_DEVICE_PATH;
 typedef struct _EFI_USB_WWID_DEVICE_PATH EFI_USB_WWID_DEVICE_PATH, *PEFI_USB_WWID_DEVICE_PATH;
 typedef struct _EFI_VENDOR_DEVICE_PATH EFI_VENDOR_DEVICE_PATH, *PEFI_VENDOR_DEVICE_PATH;
 typedef struct _EFI_VLAN_DEVICE_PATH EFI_VLAN_DEVICE_PATH, *PEFI_VLAN_DEVICE_PATH;
+typedef struct _EXCEPTION_RECORD EXCEPTION_RECORD, *PEXCEPTION_RECORD;
+typedef struct _EXCEPTION_REGISTRATION_RECORD EXCEPTION_REGISTRATION_RECORD, *PEXCEPTION_REGISTRATION_RECORD;
 typedef struct _FIRMWARE_INFORMATION_BLOCK FIRMWARE_INFORMATION_BLOCK, *PFIRMWARE_INFORMATION_BLOCK;
 typedef struct _GUID GUID, *PGUID;
 typedef struct _KERNEL_INITIALIZATION_BLOCK KERNEL_INITIALIZATION_BLOCK, *PKERNEL_INITIALIZATION_BLOCK;
diff --git a/sdk/xtdk/xtuefi.h b/sdk/xtdk/xtuefi.h
index 901e782..eb11d55 100644
--- a/sdk/xtdk/xtuefi.h
+++ b/sdk/xtdk/xtuefi.h
@@ -493,7 +493,7 @@ typedef enum _EFI_PXE_BASE_CODE_CALLBACK_STATUS
     EFI_PXE_BASE_CODE_CALLBACK_STATUS_LAST
 } EFI_PXE_BASE_CODE_CALLBACK_STATUS, *PEFI_PXE_BASE_CODE_CALLBACK_STATUS;
 
-/* EFI routines forward references */
+/* EFI routine callbacks */
 typedef EFI_STATUS (*PEFI_CONVERT_POINTER)(IN UINT_PTR DebugDisposition, IN OUT PVOID *Address);
 typedef EFI_STATUS (*PEFI_ALLOCATE_PAGES)(IN EFI_ALLOCATE_TYPE Type, IN EFI_MEMORY_TYPE MemoryType, IN UINT_PTR NoPages, OUT PEFI_PHYSICAL_ADDRESS Memory);
 typedef EFI_STATUS (*PEFI_ALLOCATE_POOL)(IN EFI_MEMORY_TYPE PoolType, IN UINT_PTR Size, OUT PVOID *Buffer);