[PATCH] ArmPkg-Drivers/CpuDxe: Fix Mmu Initialization Problem.

[Kurt Kennett <Kurt.Kennett@microsoft.com>]

During Mmu initialization in the CpuDxe, for a page table any bits set 
in the 'NextSectionAttributes' are garbage and were set from bits that 
are actually part of the pagetable address.  We clear it out to zero 
so that the SyncCacheConfigPage will use the page attributes instead 
of trying to convert the (bogus) section attributes into page 
attributes.

Contributed-under: TianoCore Contribution Agreement 1.0

Signed-off-by: Kurt Kennett <mailto:kurt.kennett@microsoft.com>
---
ArmPkg/Drivers/CpuDxe/Arm/Mmu.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c 
b/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c index 63da8ba..64ef1bb 100644
--- a/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c
+++ b/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c
@@ -297,6 +297,11 @@ SyncCacheConfig (
       }
       NextRegionLength += TT_DESCRIPTOR_SECTION_SIZE;
     } else if (TT_DESCRIPTOR_SECTION_TYPE_IS_PAGE_TABLE(FirstLevelTable[i])) {
+      // In this case any bits set in the 'NextSectionAttributes' are garbage and were set from
+      // bits that are actually part of the pagetable address.  We clear it out to zero so that
+      // the SyncCacheConfigPage will use the page attributes instead of trying to convert the
+      // section attributes into page attributes
+      NextSectionAttributes = 0;
       Status = SyncCacheConfigPage (
           i,FirstLevelTable[i],
           NumberOfDescriptors, MemorySpaceMap,
--
2.9.0.windows

K2