[edk2-devel] [PATCH v5 13/16] UefiCpuPkg: Use Attribute From SMM MemoryAttributesTable if Nonzero

["Taylor Beebe" <taylor.d.beebe@gmail.com>]

PiSmmCore fetches the EFI memory map and calls SplitTable() to
split each loaded image section into its own descriptor with
EFI_MEMORY_XP marking data sections and EFI_MEMORY_RO marking
code sections.

The SMM MAT logic is almost identical to the DXE MAT logic but goes
a step further and also updates the memory map descriptors which describe
image code and data sections to be of type EfiRuntimeServicesCode and
EfiRuntimeServicesData respectively. The consolidated MAT logic
(present in the new ImagePropertiesRecordLib) more closely follows
the DXE MAT logic which identifies image code sections by the presence
of the attribute EFI_MEMORY_RO in the descriptor and image data
sections by the presence of the attribute EFI_MEMORY_XP. Because of
the flow choice of the consolidated MAT logic, the SMM MAT logic should
just use the attributes from the table returned by SplitTable().

Additionally, the function EnforceMemoryMapAttribute() in the SMM MAT
logic will ensure that the CODE and DATA memory types have the desired
attributes so bisecting this patch series at this commit will still
function as before.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Taylor Beebe <taylor.d.beebe@gmail.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
---
 UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c
index 3d445df213ab..15f998e501a2 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c
@@ -1047,14 +1047,17 @@ SetMemMapAttributes (
   MemoryMap = MemoryMapStart;
   for (Index = 0; Index < MemoryMapEntryCount; Index++) {
     DEBUG ((DEBUG_VERBOSE, "SetAttribute: Memory Entry - 0x%lx, 0x%x\n", MemoryMap->PhysicalStart, MemoryMap->NumberOfPages));
-    if (MemoryMap->Type == EfiRuntimeServicesCode) {
-      MemoryAttribute = EFI_MEMORY_RO;
-    } else {
-      ASSERT ((MemoryMap->Type == EfiRuntimeServicesData) || (MemoryMap->Type == EfiConventionalMemory));
-      //
-      // Set other type memory as NX.
-      //
-      MemoryAttribute = EFI_MEMORY_XP;
+    MemoryAttribute = MemoryMap->Attribute & EFI_MEMORY_ACCESS_MASK;
+    if (MemoryAttribute == 0) {
+      if (MemoryMap->Type == EfiRuntimeServicesCode) {
+        MemoryAttribute = EFI_MEMORY_RO;
+      } else {
+        ASSERT ((MemoryMap->Type == EfiRuntimeServicesData) || (MemoryMap->Type == EfiConventionalMemory));
+        //
+        // Set other type memory as NX.
+        //
+        MemoryAttribute = EFI_MEMORY_XP;
+      }
     }
 
     //
-- 
2.42.0.windows.2



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