[edk2-devel] [PATCH v5 09/16] MdeModulePkg: Fix MAT Descriptor Count Calculation

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

|4K PAGE|DATA|CODE|DATA|CODE|DATA|4K PAGE|
Say the above memory region is currently one memory map descriptor.
The above image memory layout example contains two code sections
oriented in a way that maximizes the number of descriptors which
would be required to describe each section.

NOTE: It's unlikely that a data section would ever be between
two code sections, but it's still handled by the below formula
for correctness.

There are two code sections (let's say CodeSegmentMax == 2),
three data sections, and two unrelated memory regions flanking the
image. The number of required descriptors to describe this layout
will be 2 * 2 + 3 == 7. This patch updates the calculations to account
for the worst-case scenario.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Dandan Bi <dandan.bi@intel.com>
Signed-off-by: Taylor Beebe <taylor.d.beebe@gmail.com>
Reviewed-by: Liming Gao <gaoliming@byosoft.com.cn>
---
 MdeModulePkg/Core/Dxe/Misc/MemoryAttributesTable.c                       | 2 +-
 MdeModulePkg/Library/ImagePropertiesRecordLib/ImagePropertiesRecordLib.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/MdeModulePkg/Core/Dxe/Misc/MemoryAttributesTable.c b/MdeModulePkg/Core/Dxe/Misc/MemoryAttributesTable.c
index 51630f504ea1..af6c26244cc0 100644
--- a/MdeModulePkg/Core/Dxe/Misc/MemoryAttributesTable.c
+++ b/MdeModulePkg/Core/Dxe/Misc/MemoryAttributesTable.c
@@ -517,7 +517,7 @@ CoreGetMemoryMapWithSeparatedImageSection (
 
   CoreAcquiremMemoryAttributesTableLock ();
 
-  AdditionalRecordCount = (2 * mImagePropertiesPrivateData.CodeSegmentCountMax + 1) * mImagePropertiesPrivateData.ImageRecordCount;
+  AdditionalRecordCount = (2 * mImagePropertiesPrivateData.CodeSegmentCountMax + 3) * mImagePropertiesPrivateData.ImageRecordCount;
 
   OldMemoryMapSize = *MemoryMapSize;
   Status           = CoreGetMemoryMap (MemoryMapSize, MemoryMap, MapKey, DescriptorSize, DescriptorVersion);
diff --git a/MdeModulePkg/Library/ImagePropertiesRecordLib/ImagePropertiesRecordLib.c b/MdeModulePkg/Library/ImagePropertiesRecordLib/ImagePropertiesRecordLib.c
index 9fb3b922038f..7c0ecd07c1bb 100644
--- a/MdeModulePkg/Library/ImagePropertiesRecordLib/ImagePropertiesRecordLib.c
+++ b/MdeModulePkg/Library/ImagePropertiesRecordLib/ImagePropertiesRecordLib.c
@@ -277,7 +277,7 @@ GetMaxSplitRecordCount (
       break;
     }
 
-    SplitRecordCount += (2 * ImageRecord->CodeSegmentCount + 1);
+    SplitRecordCount += (2 * ImageRecord->CodeSegmentCount + 3);
     PhysicalStart     = ImageRecord->ImageBase + ImageRecord->ImageSize;
   } while ((ImageRecord != NULL) && (PhysicalStart < PhysicalEnd));
 
-- 
2.42.0.windows.2



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