UefiCpuPkg/MtrrLib: Fix MtrrDebugPrintAllMtrrsWorker to avoid hang

ARRAY_SIZE(Mtrrs->Variables.Mtrr) was used in
MtrrDebugPrintAllMtrrsWorker() to parse the MTRR registers.
Instead, the actual variable MTRR count should be used.
Otherwise, the uninitialized random data in MtrrSetting may cause
MtrrLibSetMemoryType() hang.

Steven Shi found this bug in QEMU when using Q35 chip.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Steven Shi <steven.shi@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
This commit is contained in:
Ruiyu Ni 2017-10-17 09:46:27 +08:00
parent e2ac374f85
commit 1c29d03869
1 changed files with 6 additions and 3 deletions

View File

@ -2776,6 +2776,7 @@ MtrrDebugPrintAllMtrrsWorker (
UINTN RangeCount;
UINT64 MtrrValidBitsMask;
UINT64 MtrrValidAddressMask;
UINT32 VariableMtrrCount;
MTRR_MEMORY_RANGE Ranges[
ARRAY_SIZE (mMtrrLibFixedMtrrTable) * sizeof (UINT64) + 2 * ARRAY_SIZE (Mtrrs->Variables.Mtrr) + 1
];
@ -2785,6 +2786,8 @@ MtrrDebugPrintAllMtrrsWorker (
return;
}
VariableMtrrCount = GetVariableMtrrCountWorker ();
if (MtrrSetting != NULL) {
Mtrrs = MtrrSetting;
} else {
@ -2802,7 +2805,7 @@ MtrrDebugPrintAllMtrrsWorker (
DEBUG((DEBUG_CACHE, "Fixed MTRR[%02d] : %016lx\n", Index, Mtrrs->Fixed.Mtrr[Index]));
}
for (Index = 0; Index < ARRAY_SIZE (Mtrrs->Variables.Mtrr); Index++) {
for (Index = 0; Index < VariableMtrrCount; Index++) {
if (((MSR_IA32_MTRR_PHYSMASK_REGISTER *)&Mtrrs->Variables.Mtrr[Index].Mask)->Bits.V == 0) {
//
// If mask is not valid, then do not display range
@ -2829,11 +2832,11 @@ MtrrDebugPrintAllMtrrsWorker (
RangeCount = 1;
MtrrLibGetRawVariableRanges (
&Mtrrs->Variables, ARRAY_SIZE (Mtrrs->Variables.Mtrr),
&Mtrrs->Variables, VariableMtrrCount,
MtrrValidBitsMask, MtrrValidAddressMask, RawVariableRanges
);
MtrrLibApplyVariableMtrrs (
RawVariableRanges, ARRAY_SIZE (RawVariableRanges),
RawVariableRanges, VariableMtrrCount,
Ranges, ARRAY_SIZE (Ranges), &RangeCount
);