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| author | Ruiyu Ni <ruiyu.ni@intel.com> | 2017-10-19 10:43:08 +0800 |
|---|---|---|
| committer | Ruiyu Ni <ruiyu.ni@intel.com> | 2017-10-20 12:52:08 +0800 |
| commit | 86cabbcfa005ca9c9589402d4fb7c984e741cc19 (patch) | |
| tree | d1d3dbdef98ed558fc43f95876ea53a103f7e963 /UefiCpuPkg/Library/MtrrLib | |
| parent | 1e3f7a3782f1928a19bba81d9d0dba28d15fdae5 (diff) | |
| download | edk2-86cabbcfa005ca9c9589402d4fb7c984e741cc19.tar.gz edk2-86cabbcfa005ca9c9589402d4fb7c984e741cc19.tar.bz2 edk2-86cabbcfa005ca9c9589402d4fb7c984e741cc19.zip | |
UefiCpuPkg/MtrrLib: Fix bug that may incorrectly set <1MB attribute
MtrrLibSetBelow1MBMemoryAttribute() may be called multiple times.
It's possible that in a 2nd call, Modified[0] is set to TRUE in
1st call but ClearMasks[0] and OrMasks[0] is uninitialized in
2nd call. It causes FixedSettings->Mtrr[0] be set to random
data.
The patch fixes this issue by introducing a local Modified[]
array and only updates FixedSettings->Mtrr[] when LocalModified[i]
is TRUE.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Hao A Wu <hao.a.wu@intel.com>
Diffstat (limited to 'UefiCpuPkg/Library/MtrrLib')
| -rw-r--r-- | UefiCpuPkg/Library/MtrrLib/MtrrLib.c | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/UefiCpuPkg/Library/MtrrLib/MtrrLib.c b/UefiCpuPkg/Library/MtrrLib/MtrrLib.c index cb22558103..200becdd4a 100644 --- a/UefiCpuPkg/Library/MtrrLib/MtrrLib.c +++ b/UefiCpuPkg/Library/MtrrLib/MtrrLib.c @@ -2114,22 +2114,32 @@ MtrrLibSetBelow1MBMemoryAttribute ( UINT64 OrMask;
UINT64 ClearMasks[ARRAY_SIZE (mMtrrLibFixedMtrrTable)];
UINT64 OrMasks[ARRAY_SIZE (mMtrrLibFixedMtrrTable)];
+ BOOLEAN LocalModified[ARRAY_SIZE (mMtrrLibFixedMtrrTable)];
ASSERT (BaseAddress < BASE_1MB);
+ SetMem (LocalModified, sizeof (LocalModified), FALSE);
+
+ //
+ // (Value & ~0 | 0) still equals to (Value)
+ //
+ SetMem64 (ClearMasks, sizeof (ClearMasks), 0);
+ SetMem64 (OrMasks, sizeof (OrMasks), 0);
+
MsrIndex = (UINT32)-1;
while ((BaseAddress < BASE_1MB) && (Length != 0)) {
Status = MtrrLibProgramFixedMtrr (Type, &BaseAddress, &Length, &MsrIndex, &ClearMask, &OrMask);
if (RETURN_ERROR (Status)) {
return Status;
}
- ClearMasks[MsrIndex] = ClearMask;
- OrMasks[MsrIndex] = OrMask;
- Modified[MsrIndex] = TRUE;
+ ClearMasks[MsrIndex] = ClearMask;
+ OrMasks[MsrIndex] = OrMask;
+ Modified[MsrIndex] = TRUE;
+ LocalModified[MsrIndex] = TRUE;
}
for (MsrIndex = 0; MsrIndex < ARRAY_SIZE (mMtrrLibFixedMtrrTable); MsrIndex++) {
- if (Modified[MsrIndex]) {
+ if (LocalModified[MsrIndex]) {
FixedSettings->Mtrr[MsrIndex] = (FixedSettings->Mtrr[MsrIndex] & ~ClearMasks[MsrIndex]) | OrMasks[MsrIndex];
}
}
@@ -2354,6 +2364,7 @@ MtrrSetMemoryAttributesInMtrrSettings ( //
// 3. Apply the below-1MB memory attribute settings.
//
+ ZeroMem (WorkingFixedSettings.Mtrr, sizeof (WorkingFixedSettings.Mtrr));
for (Index = 0; Index < RangeCount; Index++) {
if (Ranges[Index].BaseAddress >= BASE_1MB) {
continue;
|