3 files changed, 76 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/BaseLib.inf b/MdePkg/Library/BaseLib/BaseLib.inf
index 6d03f941fd..97ff9cf71a 100644
--- a/MdePkg/Library/BaseLib/BaseLib.inf
+++ b/MdePkg/Library/BaseLib/BaseLib.inf
@@ -66,6 +66,8 @@
   BaseLibInternals.h
 
 [Sources.Ia32]
+  Ia32/Lfence.nasm
+
   Ia32/Wbinvd.c | MSFT 
   Ia32/WriteMm7.c | MSFT 
   Ia32/WriteMm6.c | MSFT 
@@ -378,6 +380,7 @@
   X64/SwitchStack.asm
   X64/EnableCache.asm
   X64/DisableCache.asm
+  X64/Lfence.nasm
 
   X64/CpuBreakpoint.c | MSFT 
   X64/WriteMsr64.c | MSFT 
diff --git a/MdePkg/Library/BaseLib/Ia32/Lfence.nasm b/MdePkg/Library/BaseLib/Ia32/Lfence.nasm
new file mode 100644
index 0000000000..414f7d7344
--- /dev/null
+++ b/MdePkg/Library/BaseLib/Ia32/Lfence.nasm
@@ -0,0 +1,36 @@
+;------------------------------------------------------------------------------ ;
+; Copyright (c) 2018, Intel Corporation. All rights reserved.<BR>
+; This program and the accompanying materials
+; are licensed and made available under the terms and conditions of the BSD License
+; which accompanies this distribution.  The full text of the license may be found at
+; http://opensource.org/licenses/bsd-license.php.
+;
+; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+;
+; Module Name:
+;
+;   Lfence.nasm
+;
+; Abstract:
+;
+;   Performs a serializing operation on all load-from-memory instructions that
+;   were issued prior to the call of this function.
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+    SECTION .text
+
+;------------------------------------------------------------------------------
+; VOID
+; EFIAPI
+; AsmLfence (
+;   VOID
+;   );
+;------------------------------------------------------------------------------
+global ASM_PFX(AsmLfence)
+ASM_PFX(AsmLfence):
+    lfence
+    ret
diff --git a/MdePkg/Library/BaseLib/X64/Lfence.nasm b/MdePkg/Library/BaseLib/X64/Lfence.nasm
new file mode 100644
index 0000000000..9ee9b563e2
--- /dev/null
+++ b/MdePkg/Library/BaseLib/X64/Lfence.nasm
@@ -0,0 +1,37 @@
+;------------------------------------------------------------------------------ ;
+; Copyright (c) 2018, Intel Corporation. All rights reserved.<BR>
+; This program and the accompanying materials
+; are licensed and made available under the terms and conditions of the BSD License
+; which accompanies this distribution.  The full text of the license may be found at
+; http://opensource.org/licenses/bsd-license.php.
+;
+; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+;
+; Module Name:
+;
+;   Lfence.nasm
+;
+; Abstract:
+;
+;   Performs a serializing operation on all load-from-memory instructions that
+;   were issued prior to the call of this function.
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+    DEFAULT REL
+    SECTION .text
+
+;------------------------------------------------------------------------------
+; VOID
+; EFIAPI
+; AsmLfence (
+;   VOID
+;   );
+;------------------------------------------------------------------------------
+global ASM_PFX(AsmLfence)
+ASM_PFX(AsmLfence):
+    lfence
+    ret