UefiCpuPkg/PiSmmCpuDxeSmm: Enable/Restore XD in SMM

[mirror_edk2.git] / UefiCpuPkg / PiSmmCpuDxeSmm / MpService.c

diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c b/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c
index 79b7c90a809be8eb72e54c269a640e0397fda154..185cb3d5935fe92ebf79a785487c392e080a0d69 100644 (file)
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c
@@ -1,7 +1,7 @@
 /** @file\r
 SMM MP service implementation\r
 \r
-Copyright (c) 2009 - 2015, Intel Corporation. All rights reserved.<BR>\r
+Copyright (c) 2009 - 2016, 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
@@ -1019,6 +1019,7 @@ SmiRendezvous (
   BOOLEAN           BspInProgress;\r
   UINTN             Index;\r
   UINTN             Cr2;\r
+  BOOLEAN           XdDisableFlag;\r
 \r
   //\r
   // Save Cr2 because Page Fault exception in SMM may override its value\r
@@ -1078,9 +1079,14 @@ SmiRendezvous (
     }\r
 \r
     //\r
-    // Try to enable NX\r
+    // Try to enable XD\r
     //\r
+    XdDisableFlag = FALSE;\r
     if (mXdSupported) {\r
+      if ((AsmReadMsr64 (MSR_IA32_MISC_ENABLE) & B_XD_DISABLE_BIT) != 0) {\r
+        XdDisableFlag = TRUE;\r
+        AsmMsrAnd64 (MSR_IA32_MISC_ENABLE, ~B_XD_DISABLE_BIT);\r
+      }\r
       ActivateXd ();\r
     }\r
 \r
@@ -1152,7 +1158,6 @@ SmiRendezvous (
         // BSP Handler is always called with a ValidSmi == TRUE\r
         //\r
         BSPHandler (CpuIndex, mSmmMpSyncData->EffectiveSyncMode);\r
-\r
       } else {\r
         APHandler (CpuIndex, ValidSmi, mSmmMpSyncData->EffectiveSyncMode);\r
       }\r
@@ -1165,6 +1170,13 @@ SmiRendezvous (
     //\r
     while (mSmmMpSyncData->AllCpusInSync) {\r
       CpuPause ();\r
+     }\r
+\r
+    //\r
+    // Restore XD\r
+    //\r
+    if (XdDisableFlag) {\r
+      AsmMsrOr64 (MSR_IA32_MISC_ENABLE, B_XD_DISABLE_BIT);\r
     }\r
   }\r
 \r