UefiCpuPkg: Replace BSD License with BSD+Patent License

[mirror_edk2.git] / UefiCpuPkg / Include / Library / SmmCpuFeaturesLib.h

diff --git a/UefiCpuPkg/Include/Library/SmmCpuFeaturesLib.h b/UefiCpuPkg/Include/Library/SmmCpuFeaturesLib.h
index 4478003467c88d30f7500032650ff991bc75b143..e6c5679e13966ec25c894f161008743f5f7deb1b 100644 (file)
--- a/UefiCpuPkg/Include/Library/SmmCpuFeaturesLib.h
+++ b/UefiCpuPkg/Include/Library/SmmCpuFeaturesLib.h
@@ -1,14 +1,8 @@
 /** @file\r
 Library that provides CPU specific functions to support the PiSmmCpuDxeSmm module.\r
 \r
-Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>\r
-This program and the accompanying materials\r
-are licensed and made available under the terms and conditions of the BSD License\r
-which accompanies this distribution.  The full text of the license may be found at\r
-http://opensource.org/licenses/bsd-license.php\r
-\r
-THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
-WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
+Copyright (c) 2015 - 2019, Intel Corporation. All rights reserved.<BR>\r
+SPDX-License-Identifier: BSD-2-Clause-Patent\r
 \r
 **/\r
 \r
@@ -160,14 +154,33 @@ SmmCpuFeaturesGetSmiHandlerSize (
   than zero and is called by the CPU that was elected as monarch during System\r
   Management Mode initialization.\r
 \r
+    //\r
+    // Append Shadow Stack after normal stack\r
+    //\r
+    // |= SmiStack\r
+    // +--------------------------------------------------+---------------------------------------------------------------+\r
+    // | Known Good Stack | Guard Page |    SMM Stack     | Known Good Shadow Stack | Guard Page |    SMM Shadow Stack    |\r
+    // +--------------------------------------------------+---------------------------------------------------------------+\r
+    // |                               |PcdCpuSmmStackSize|                                      |PcdCpuSmmShadowStackSize|\r
+    // |<-------------------- StackSize ----------------->|<------------------------- ShadowStackSize ------------------->|\r
+    // |                                                                                                                  |\r
+    // |<-------------------------------------------- Processor N ------------------------------------------------------->|\r
+    // | low address (bottom)                                                                          high address (top) |\r
+    //\r
+\r
   @param[in] CpuIndex   The index of the CPU to install the custom SMI handler.\r
                         The value must be between 0 and the NumberOfCpus field\r
                         in the System Management System Table (SMST).\r
   @param[in] SmBase     The SMBASE address for the CPU specified by CpuIndex.\r
-  @param[in] SmiStack   The stack to use when an SMI is processed by the\r
+  @param[in] SmiStack   The bottom of stack to use when an SMI is processed by the\r
                         the CPU specified by CpuIndex.\r
   @param[in] StackSize  The size, in bytes, if the stack used when an SMI is\r
                         processed by the CPU specified by CpuIndex.\r
+                        StackSize should be PcdCpuSmmStackSize, with 2 more pages\r
+                        if PcdCpuSmmStackGuard is true.\r
+                        If ShadowStack is enabled, the shadow stack is allocated\r
+                        after the normal Stack. The size is PcdCpuSmmShadowStackSize.\r
+                        with 2 more pages if PcdCpuSmmStackGuard is true.\r
   @param[in] GdtBase    The base address of the GDT to use when an SMI is\r
                         processed by the CPU specified by CpuIndex.\r
   @param[in] GdtSize    The size, in bytes, of the GDT used when an SMI is\r