diff options
| author | Jeff Fan <jeff.fan@intel.com> | 2015-11-20 01:22:00 +0000 |
|---|---|---|
| committer | vanjeff <vanjeff@Edk2> | 2015-11-20 01:22:00 +0000 |
| commit | f6bc3a6d2623c317cefb990d4ae7cbcfc04008b9 (patch) | |
| tree | f6c825d3d752f1e49f89a6eecd31cc3c8791d0a2 /UefiCpuPkg | |
| parent | d855b261d19e2c21c059293befe6ab37db1e8efb (diff) | |
| download | edk2-platforms-f6bc3a6d2623c317cefb990d4ae7cbcfc04008b9.tar.xz | |
UefiCpuPkg: Not touch SmmFeatureControl if Code_Access_Chk not Set
Bit SMM_Code_Access_Chk (SMM-RO) in MSR_SMM_MCA_CAP is defined in SDM.
If set to 1 indicates that the SMM code access restriction is supported and the
MSR_SMM_FEATURE_CONTROL is supported.
If this bit is not set, we needn't to access register SmmFetureControl.
Otherwise, #GP exception may happen.
Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Michael Kinney <michael.d.kinney@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18905 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'UefiCpuPkg')
| -rw-r--r-- | UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c | 13 |
1 files changed, 3 insertions, 10 deletions
diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c index de681c0a30..532ac0974b 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c @@ -1309,9 +1309,9 @@ ConfigSmmCodeAccessCheckOnCurrentProcessor ( NewSmmFeatureControlMsr = SmmFeatureControlMsr;
if (mSmmCodeAccessCheckEnable) {
NewSmmFeatureControlMsr |= SMM_CODE_CHK_EN_BIT;
- }
- if (FeaturePcdGet (PcdCpuSmmFeatureControlMsrLock)) {
- NewSmmFeatureControlMsr |= SMM_FEATURE_CONTROL_LOCK_BIT;
+ if (FeaturePcdGet (PcdCpuSmmFeatureControlMsrLock)) {
+ NewSmmFeatureControlMsr |= SMM_FEATURE_CONTROL_LOCK_BIT;
+ }
}
//
@@ -1354,13 +1354,6 @@ ConfigSmmCodeAccessCheck ( //
if ((AsmReadMsr64 (EFI_MSR_SMM_MCA_CAP) & SMM_CODE_ACCESS_CHK_BIT) == 0) {
mSmmCodeAccessCheckEnable = FALSE;
- }
-
- //
- // If the SMM Code Access Check feature is disabled and the Feature Control MSR
- // is not being locked, then no additional work is required
- //
- if (!mSmmCodeAccessCheckEnable && !FeaturePcdGet (PcdCpuSmmFeatureControlMsrLock)) {
return;
}
|