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UefiCpuPkg/PiSmmCpuDxeSmm: Add SmmMemoryAttribute protocol

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Heap guard makes use of paging mechanism to implement its functionality. But
there's no protocol or library available to change page attribute in SMM mode.
A new protocol gEdkiiSmmMemoryAttributeProtocolGuid is introduced to make it
happen. This protocol provide three interfaces

struct _EDKII_SMM_MEMORY_ATTRIBUTE_PROTOCOL {
  EDKII_SMM_GET_MEMORY_ATTRIBUTES       GetMemoryAttributes;
  EDKII_SMM_SET_MEMORY_ATTRIBUTES       SetMemoryAttributes;
  EDKII_SMM_CLEAR_MEMORY_ATTRIBUTES     ClearMemoryAttributes;
};

Since heap guard feature need to update page attributes. The page table
should not set to be read-only if heap guard feature is enabled for SMM
mode. Otherwise this feature cannot work.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@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>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
This commit is contained in:
Jian J Wang
2017-11-14 10:56:14 +08:00
committed by Star Zeng
parent 235a4490c8
commit af4f4b3468
6 changed files with 307 additions and 1 deletions
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10
UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/PageTbl.c
View File

@@ -196,6 +196,16 @@ SetPageTableAttributes (
BOOLEAN IsSplitted;
BOOLEAN PageTableSplitted;
//
// Don't mark page table as read-only if heap guard is enabled.
//
// BIT2: SMM page guard enabled
// BIT3: SMM pool guard enabled
//
if ((PcdGet8 (PcdHeapGuardPropertyMask) & (BIT3 | BIT2)) != 0) {
return ;
}
DEBUG ((DEBUG_INFO, "SetPageTableAttributes\n"));
//