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MdeModulePkg PiSmmCore: Remove a hidden assumption of SMRAM reservation

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that assumes the SMRAM reserved range is only at the end of the SMRAM descriptor.

          //
          // This range has reserved area, calculate the left free size
          //
          gSmmCorePrivate->SmramRanges[Index].PhysicalSize = SmramResRegion->SmramReservedStart - gSmmCorePrivate->SmramRanges[Index].CpuStart;

Imagine the following scenario where we just reserve the first page of the SMRAM range:

SMRAM Descriptor:
  Start: 0x80000000
  Size: 0x02000000

Reserved Range:
  Start: 0x80000000
  Size: 0x00001000

In this case the adjustment to the SMRAM range size yields zero: ReservedStart - SMRAM Start is 0x80000000 - 0x80000000 = 0.
So even though most of the range is still free the IPL code decides its unusable.

The problem comes from the email thread: [edk2] PiSmmIpl SMRAM Reservation Logic.
http://thread.gmane.org/gmane.comp.bios.tianocore.devel/15268

Also to follow the idea in the email thread, the patch is to
1. Keep only one copy of full SMRAM ranges in gSmmCorePrivate->SmramRanges,
split record for SmmConfiguration->SmramReservedRegions and SMM Core that
will be marked to be EFI_ALLOCATED in gSmmCorePrivate->SmramRanges.
2. Handle SmmConfiguration->SmramReservedRegions at beginning of, at end of,
in the middle of, or cross multiple SmramRanges.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18031 6f19259b-4bc3-4df7-8a09-765794883524
This commit is contained in:
Star Zeng
2015-07-26 07:38:12 +00:00
committed by jljusten
parent 387e7c15f5
commit c03beb762a
5 changed files with 445 additions and 85 deletions
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4
MdeModulePkg/Library/PiSmmCoreMemoryAllocationLib/MemoryAllocationLib.c
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@ -919,11 +919,11 @@ PiSmmCoreMemoryAllocationLibConstructor (
//
SmmInitializeMemoryServices (SmmCorePrivate->SmramRangeCount, SmmCorePrivate->SmramRanges);
mSmmCoreMemoryAllocLibSmramRangeCount = SmmCorePrivate->FullSmramRangeCount;
mSmmCoreMemoryAllocLibSmramRangeCount = SmmCorePrivate->SmramRangeCount;
Size = mSmmCoreMemoryAllocLibSmramRangeCount * sizeof (EFI_SMRAM_DESCRIPTOR);
mSmmCoreMemoryAllocLibSmramRanges = (EFI_SMRAM_DESCRIPTOR *) AllocatePool (Size);
ASSERT (mSmmCoreMemoryAllocLibSmramRanges != NULL);
CopyMem (mSmmCoreMemoryAllocLibSmramRanges, SmmCorePrivate->FullSmramRanges, Size);
CopyMem (mSmmCoreMemoryAllocLibSmramRanges, SmmCorePrivate->SmramRanges, Size);
return EFI_SUCCESS;
}