Heap guard feature needs paging to work properly. 64-bit BIOS uses
PcdDxeIplBuildPageTables to control the page table setup. 32-bit BIOS
has to check heap guard feature to decide enabling paging or not.
Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
---
MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf | 1 +
MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c | 36 ++++++++++++++++++++++---
2 files changed, 33 insertions(+), 4 deletions(-)
diff --git a/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf b/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
index 9d0e76a293..a1b8748432 100644
--- a/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
+++ b/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
@@ -116,6 +116,7 @@
gEfiMdeModulePkgTokenSpaceGuid.PcdUse1GPageTable ## SOMETIMES_CONSUMES
gEfiMdeModulePkgTokenSpaceGuid.PcdPteMemoryEncryptionAddressOrMask ## CONSUMES
gEfiMdeModulePkgTokenSpaceGuid.PcdNullPointerDetectionPropertyMask ## CONSUMES
+ gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask ## CONSUMES
[Pcd.IA32,Pcd.X64,Pcd.ARM,Pcd.AARCH64]
gEfiMdeModulePkgTokenSpaceGuid.PcdSetNxForStack ## SOMETIMES_CONSUMES
diff --git a/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c b/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
index 96f5718444..5649265367 100644
--- a/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
+++ b/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
@@ -211,6 +211,37 @@ IsExecuteDisableBitAvailable (
return Available;
}
+/**
+ The function will check if page table should be setup or not.
+
+ @retval TRUE Page table should be created.
+ @retval FALSE Page table should not be created.
+
+**/
+BOOLEAN
+ToBuildPageTable (
+ VOID
+ )
+{
+ if (!IsIa32PaeSupport ()) {
+ return FALSE;
+ }
+
+ if (IsNullDetectionEnabled ()) {
+ return TRUE;
+ }
+
+ if (PcdGet8 (PcdHeapGuardPropertyMask) != 0) {
+ return TRUE;
+ }
+
+ if (PcdGetBool (PcdSetNxForStack) && IsExecuteDisableBitAvailable ()) {
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
/**
Transfers control to DxeCore.
@@ -385,10 +416,7 @@ HandOffToDxeCore (
TopOfStack = (EFI_PHYSICAL_ADDRESS) (UINTN) ALIGN_POINTER (TopOfStack, CPU_STACK_ALIGNMENT);
PageTables = 0;
- BuildPageTablesIa32Pae = (BOOLEAN) (IsIa32PaeSupport () &&
- (IsNullDetectionEnabled () ||
- (PcdGetBool (PcdSetNxForStack) &&
- IsExecuteDisableBitAvailable ())));
+ BuildPageTablesIa32Pae = ToBuildPageTable ();
if (BuildPageTablesIa32Pae) {
PageTables = Create4GPageTablesIa32Pae (BaseOfStack, STACK_SIZE);
if (IsExecuteDisableBitAvailable ()) {
--
2.14.1.windows.1
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