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IntelFrameworkModulePkg/Csm: Set CSM memory executable 

Commit b22a62be5c
* IntelFrameworkModule/LegacyBios:Use reserved memory for legacy data
allocates reserved memory for holding legacy code/data.

But with PcdDxeNxMemoryProtectionPolicy set to certain value to
forbid execution when code is in certain type of memory, it's
possible that a platform forbids execution when code is in reserved
memory. The patch calls GCD service to allow such case otherwise
CPU exception may occur.

Code execution in BSCode area should be enabled by platform by
default.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jian Wang <jian.j.wang@intel.com>
This commit is contained in:
Ruiyu Ni 2018-08-06 17:56:37 +08:00
parent 0e967dff06
commit cd25509b1f
1 changed files with 26 additions and 8 deletions
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34
IntelFrameworkModulePkg/Csm/LegacyBiosDxe/LegacyBios.c
View File

@ -43,7 +43,7 @@ UINTN mStructureTablePages = 0;
BOOLEAN mEndOfDxe = FALSE;
/**
Allocate memory for legacy usage.
Allocate memory for legacy usage. The memory is executable.
@param AllocateType The type of allocation to perform.
@param MemoryType The type of memory to allocate.
@ -51,8 +51,8 @@ BOOLEAN mEndOfDxe = FALSE;
@param Pages Number of pages to allocate
@param Result Result of allocation
@retval EFI_SUCCESS Legacy16 code loaded
@retval Other No protocol installed, unload driver.
@retval EFI_SUCCESS Legacy memory is allocated successfully.
@retval Other Legacy memory is not allocated.
**/
EFI_STATUS
@ -64,8 +64,9 @@ AllocateLegacyMemory (
OUT EFI_PHYSICAL_ADDRESS *Result
)
{
EFI_STATUS Status;
EFI_PHYSICAL_ADDRESS MemPage;
EFI_STATUS Status;
EFI_PHYSICAL_ADDRESS MemPage;
EFI_GCD_MEMORY_SPACE_DESCRIPTOR MemDesc;
//
// Allocate Pages of memory less <= StartPageAddress
@ -81,12 +82,29 @@ AllocateLegacyMemory (
// Do not ASSERT on Status error but let caller decide since some cases
// memory is already taken but that is ok.
//
if (!EFI_ERROR (Status)) {
if (MemoryType != EfiBootServicesCode) {
//
// Make sure that the buffer can be used to store code.
//
Status = gDS->GetMemorySpaceDescriptor (MemPage, &MemDesc);
if (!EFI_ERROR (Status) && (MemDesc.Attributes & EFI_MEMORY_XP) != 0) {
Status = gDS->SetMemorySpaceAttributes (
MemPage,
EFI_PAGES_TO_SIZE (Pages),
MemDesc.Attributes & (~EFI_MEMORY_XP)
);
}
if (EFI_ERROR (Status)) {
gBS->FreePages (MemPage, Pages);
}
}
}
if (!EFI_ERROR (Status)) {
*Result = (EFI_PHYSICAL_ADDRESS) (UINTN) MemPage;
}
//
// If reach here the status = EFI_SUCCESS
//
return Status;
}