see https://github.com/thenickdude/pve-edk2-firmware

edk2-revert-2ac1730-147fd35-for-hackintosh.patch

From c3f09abd9ad45ce453fec29c68af0e4c68f71e84 Mon Sep 17 00:00:00 2001
From: Nicholas Sherlock <[email protected]>
Date: Mon, 30 Apr 2018 12:59:13 +1200
Subject: [PATCH] Revert readonly pagetables introduced by 2ac1730 and 147fd35

---
 .../Core/DxeIplPeim/Ia32/DxeLoadFunc.c        |  6 ------
 .../Core/DxeIplPeim/X64/VirtualMemory.c       |  6 ------
 UefiCpuPkg/CpuDxe/CpuPageTable.c              | 21 ++++++++++++-------
 3 files changed, 13 insertions(+), 20 deletions(-)

diff --git a/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c b/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
index 172d7cd1c6..803fbf9bb4 100644
--- a/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
+++ b/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
@@ -143,12 +143,6 @@ Create4GPageTablesIa32Pae (
       );
   }
 
-  //
-  // Protect the page table by marking the memory used for page table to be
-  // read-only.
-  //
-  EnablePageTableProtection ((UINTN)PageMap, FALSE);
-
   return (UINTN) PageMap;
 }
 
diff --git a/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c b/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c
index 516cf908bc..97ecbbc814 100644
--- a/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c
+++ b/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c
@@ -880,12 +880,6 @@ CreateIdentityMappingPageTables (
     ZeroMem (PageMapLevel5Entry, (512 - IndexOfPml5Entries) * sizeof (PAGE_MAP_AND_DIRECTORY_POINTER));
   }
 
-  //
-  // Protect the page table by marking the memory used for page table to be
-  // read-only.
-  //
-  EnablePageTableProtection ((UINTN)PageMap, TRUE);
-
   //
   // Set IA32_EFER.NXE if necessary.
   //
diff --git a/UefiCpuPkg/CpuDxe/CpuPageTable.c b/UefiCpuPkg/CpuDxe/CpuPageTable.c
index ec5cd424fc..27bc4dc130 100644
--- a/UefiCpuPkg/CpuDxe/CpuPageTable.c
+++ b/UefiCpuPkg/CpuDxe/CpuPageTable.c
@@ -1060,7 +1060,6 @@ InitializePageTablePool (
   )
 {
   VOID                      *Buffer;
-  BOOLEAN                   IsModified;
 
   //
   // Do not allow re-entrance.
@@ -1070,7 +1069,6 @@ InitializePageTablePool (
   }
 
   mPageTablePoolLock = TRUE;
-  IsModified = FALSE;
 
   //
   // Always reserve at least PAGE_TABLE_POOL_UNIT_PAGES, including one page for
@@ -1116,17 +1114,16 @@ InitializePageTablePool (
     NULL,
     (PHYSICAL_ADDRESS)(UINTN)Buffer,
     EFI_PAGES_TO_SIZE (PoolPages),
-    EFI_MEMORY_RO,
+    0,
     PageActionSet,
     AllocatePageTableMemory,
     NULL,
-    &IsModified
+    NULL
     );
-  ASSERT (IsModified == TRUE);
 
 Done:
   mPageTablePoolLock = FALSE;
-  return IsModified;
+  return TRUE;
 }
 
 /**
@@ -1347,9 +1344,17 @@ InitializePageTableLib (
   if (CurrentPagingContext.ContextData.X64.PageTableBase != 0 &&
       (CurrentPagingContext.ContextData.Ia32.Attributes &
        PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_PAE) != 0) {
-    DisableReadOnlyPageWriteProtect ();
+
+    BOOLEAN IsWpEnabled;
+
+    IsWpEnabled = IsReadOnlyPageWriteProtected ();
+    if (IsWpEnabled) {
+      DisableReadOnlyPageWriteProtect ();
+    }
     InitializePageTablePool (1);
-    EnableReadOnlyPageWriteProtect ();
+    if (IsWpEnabled) {
+      EnableReadOnlyPageWriteProtect ();
+    }
   }
 
   if (HEAP_GUARD_NONSTOP_MODE || NULL_DETECTION_NONSTOP_MODE) {