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MdeModulePkg/PiSmmCore: remove NX attr for SMM RAM

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If PcdDxeNxMemoryProtectionPolicy is set to enable protection for memory
of EfiReservedMemoryType, the BIOS will hang at a page fault exception
during starting SMM driver.

The root cause is that SMM RAM is type of EfiReservedMemoryType and
marked as non-executable. The fix is simply removing NX attribute for
those memory.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
(cherry picked from commit 94c0129d24)
This commit is contained in:
Jian J Wang
2018-01-15 10:21:08 +08:00
committed by Star Zeng
parent 79e67b2967
commit 4fd863634a
1 changed files with 16 additions and 2 deletions
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18
MdeModulePkg/Core/PiSmmCore/PiSmmIpl.c
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@@ -1550,6 +1550,7 @@ SmmIplEntry (
EFI_CPU_ARCH_PROTOCOL *CpuArch;
EFI_STATUS SetAttrStatus;
EFI_SMRAM_DESCRIPTOR *SmramRangeSmmDriver;
EFI_GCD_MEMORY_SPACE_DESCRIPTOR MemDesc;
//
// Fill in the image handle of the SMM IPL so the SMM Core can use this as the
@@ -1616,7 +1617,8 @@ SmmIplEntry (
GetSmramCacheRange (mCurrentSmramRange, &mSmramCacheBase, &mSmramCacheSize);
//
// If CPU AP is present, attempt to set SMRAM cacheability to WB
// If CPU AP is present, attempt to set SMRAM cacheability to WB and clear
// XP if it's set.
// Note that it is expected that cacheability of SMRAM has been set to WB if CPU AP
// is not available here.
//
@@ -1630,7 +1632,19 @@ SmmIplEntry (
);
if (EFI_ERROR (Status)) {
DEBUG ((DEBUG_WARN, "SMM IPL failed to set SMRAM window to EFI_MEMORY_WB\n"));
}
}
Status = gDS->GetMemorySpaceDescriptor(
mCurrentSmramRange->PhysicalStart,
&MemDesc
);
if (!EFI_ERROR (Status) && (MemDesc.Attributes & EFI_MEMORY_XP) != 0) {
gDS->SetMemorySpaceAttributes (
mCurrentSmramRange->PhysicalStart,
mCurrentSmramRange->PhysicalSize,
MemDesc.Attributes & (~EFI_MEMORY_XP)
);
}
}
//
// if Loading module at Fixed Address feature is enabled, save the SMRAM base to Load