Index: /trunk/include/iprt/asm-amd64-x86.h
===================================================================
--- /trunk/include/iprt/asm-amd64-x86.h	(revision 50423)
+++ /trunk/include/iprt/asm-amd64-x86.h	(revision 50424)
@@ -186,4 +186,33 @@
 #endif
 
+
+/**
+ * Sets the content of the GDTR CPU register.
+ * @param   pIdtr   Where to load the GDTR contents from
+ */
+#if RT_INLINE_ASM_EXTERNAL
+DECLASM(void) ASMSetGDTR(const RTGDTR *pGdtr);
+#else
+DECLINLINE(void) ASMSetGDTR(const RTGDTR *pGdtr)
+{
+# if RT_INLINE_ASM_GNU_STYLE
+    __asm__ __volatile__("lgdt %0" : : "m" (*pGdtr));
+# else
+    __asm
+    {
+#  ifdef RT_ARCH_AMD64
+        mov     rax, [pGdtr]
+        lgdt    [rax]
+#  else
+        mov     eax, [pGdtr]
+        lgdt    [eax]
+#  endif
+    }
+# endif
+}
+#endif
+
+
+
 /**
  * Get the cs register.
Index: /trunk/src/VBox/Runtime/Makefile.kmk
===================================================================
--- /trunk/src/VBox/Runtime/Makefile.kmk	(revision 50423)
+++ /trunk/src/VBox/Runtime/Makefile.kmk	(revision 50424)
@@ -184,5 +184,7 @@
 	common/asm/ASMNopPause.asm \
 	common/asm/ASMGetIDTR.asm \
+	common/asm/ASMSetIDTR.asm \
 	common/asm/ASMGetGDTR.asm \
+	common/asm/ASMSetGDTR.asm \
 	common/asm/ASMGetLDTR.asm \
 	common/asm/ASMGetSegAttr.asm \
Index: /trunk/src/VBox/Runtime/common/asm/ASMSetGDTR.asm
===================================================================
--- /trunk/src/VBox/Runtime/common/asm/ASMSetGDTR.asm	(revision 50424)
+++ /trunk/src/VBox/Runtime/common/asm/ASMSetGDTR.asm	(revision 50424)
@@ -0,0 +1,52 @@
+; $Id$
+;; @file
+; IPRT - ASMSetGDTR().
+;
+
+;
+; Copyright (C) 2006-2014 Oracle Corporation
+;
+; This file is part of VirtualBox Open Source Edition (OSE), as
+; available from http://www.virtualbox.org. This file is free software;
+; you can redistribute it and/or modify it under the terms of the GNU
+; General Public License (GPL) as published by the Free Software
+; Foundation, in version 2 as it comes in the "COPYING" file of the
+; VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+; hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+;
+; The contents of this file may alternatively be used under the terms
+; of the Common Development and Distribution License Version 1.0
+; (CDDL) only, as it comes in the "COPYING.CDDL" file of the
+; VirtualBox OSE distribution, in which case the provisions of the
+; CDDL are applicable instead of those of the GPL.
+;
+; You may elect to license modified versions of this file under the
+; terms and conditions of either the GPL or the CDDL or both.
+;
+
+;*******************************************************************************
+;* Header Files                                                                *
+;*******************************************************************************
+%include "iprt/asmdefs.mac"
+
+BEGINCODE
+
+;;
+; Sets the content of the GDTR CPU register.
+; @param   pGdtr    Where to load the GDTR contents from.
+;                   msc=rcx, gcc=rdi, x86=[esp+4]
+;
+BEGINPROC_EXPORTED ASMSetGDTR
+%ifdef ASM_CALL64_MSC
+        mov     rax, rcx
+%elifdef ASM_CALL64_GCC
+        mov     rax, rdi
+%elifdef RT_ARCH_X86
+        mov     eax, [esp + 4]
+%else
+ %error "Undefined arch?"
+%endif
+        lgdt    [xAX]
+        ret
+ENDPROC ASMSetGDTR
+
Index: /trunk/src/VBox/Runtime/common/asm/ASMSetIDTR.asm
===================================================================
--- /trunk/src/VBox/Runtime/common/asm/ASMSetIDTR.asm	(revision 50424)
+++ /trunk/src/VBox/Runtime/common/asm/ASMSetIDTR.asm	(revision 50424)
@@ -0,0 +1,52 @@
+; $Id$
+;; @file
+; IPRT - ASMSetIDTR().
+;
+
+;
+; Copyright (C) 2006-2014 Oracle Corporation
+;
+; This file is part of VirtualBox Open Source Edition (OSE), as
+; available from http://www.virtualbox.org. This file is free software;
+; you can redistribute it and/or modify it under the terms of the GNU
+; General Public License (GPL) as published by the Free Software
+; Foundation, in version 2 as it comes in the "COPYING" file of the
+; VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+; hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+;
+; The contents of this file may alternatively be used under the terms
+; of the Common Development and Distribution License Version 1.0
+; (CDDL) only, as it comes in the "COPYING.CDDL" file of the
+; VirtualBox OSE distribution, in which case the provisions of the
+; CDDL are applicable instead of those of the GPL.
+;
+; You may elect to license modified versions of this file under the
+; terms and conditions of either the GPL or the CDDL or both.
+;
+
+;*******************************************************************************
+;* Header Files                                                                *
+;*******************************************************************************
+%include "iprt/asmdefs.mac"
+
+BEGINCODE
+
+;;
+; Sets the content of the IDTR CPU register.
+; @param   pIdtr    Where to load the IDTR contents from.
+;                   msc=rcx, gcc=rdi, x86=[esp+4]
+;
+BEGINPROC_EXPORTED ASMSetIDTR
+%ifdef ASM_CALL64_MSC
+        mov     rax, rcx
+%elifdef ASM_CALL64_GCC
+        mov     rax, rdi
+%elifdef RT_ARCH_X86
+        mov     eax, [esp + 4]
+%else
+ %error "Undefined arch?"
+%endif
+        lidt    [xAX]
+        ret
+ENDPROC ASMSetIDTR
+