From: Hao Wu <hao.a.wu@intel.com>
To: edk2-devel@lists.01.org
Cc: Hao Wu <hao.a.wu@intel.com>, Jiewen Yao <jiewen.yao@intel.com>
Subject: [PATCH 2/2] IntelSiliconPkg/IntelVTdDxe: Add explicit NULL pointer checks
Date: Tue, 1 Aug 2017 12:32:03 +0800 [thread overview]
Message-ID: <20170801043203.23040-3-hao.a.wu@intel.com> (raw)
In-Reply-To: <20170801043203.23040-1-hao.a.wu@intel.com>
Add explicit NULL pointer check to make the codes more straight-forward.
Cc: Jiewen Yao <jiewen.yao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
---
IntelSiliconPkg/IntelVTdDxe/TranslationTable.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/IntelSiliconPkg/IntelVTdDxe/TranslationTable.c b/IntelSiliconPkg/IntelVTdDxe/TranslationTable.c
index 0cff2cc939..5af4a4627b 100644
--- a/IntelSiliconPkg/IntelVTdDxe/TranslationTable.c
+++ b/IntelSiliconPkg/IntelVTdDxe/TranslationTable.c
@@ -862,6 +862,8 @@ SetAccessAttribute (
VTD_SECOND_LEVEL_PAGING_ENTRY *SecondLevelPagingEntry;
UINT64 Pt;
+ SecondLevelPagingEntry = NULL;
+
DEBUG ((DEBUG_INFO,"SetAccessAttribute (S%04x B%02x D%02x F%02x) (0x%016lx - 0x%08x, %x)\n", Segment, SourceId.Bits.Bus, SourceId.Bits.Device, SourceId.Bits.Function, BaseAddress, (UINTN)Length, IoMmuAccess));
VtdIndex = FindVtdIndexByPciDevice (Segment, SourceId, &ExtContextEntry, &ContextEntry);
@@ -884,7 +886,7 @@ SetAccessAttribute (
SecondLevelPagingEntry = (VOID *)(UINTN)LShiftU64 (ExtContextEntry->Bits.SecondLevelPageTranslationPointer, 12);
DEBUG ((DEBUG_VERBOSE,"SecondLevelPagingEntry - 0x%x (S%04x B%02x D%02x F%02x)\n", SecondLevelPagingEntry, Segment, SourceId.Bits.Bus, SourceId.Bits.Device, SourceId.Bits.Function));
}
- } else {
+ } else if (ContextEntry != NULL) {
if (ContextEntry->Bits.Present == 0) {
SecondLevelPagingEntry = CreateSecondLevelPagingEntry (VtdIndex, 0);
DEBUG ((DEBUG_VERBOSE,"SecondLevelPagingEntry - 0x%x (S%04x B%02x D%02x F%02x) New\n", SecondLevelPagingEntry, Segment, SourceId.Bits.Bus, SourceId.Bits.Device, SourceId.Bits.Function));
@@ -959,7 +961,7 @@ AlwaysEnablePageAttribute (
ExtContextEntry->Bits.SecondLevelPageTranslationPointer = Pt;
ExtContextEntry->Bits.DomainIdentifier = ((1 << (UINT8)((UINTN)mVtdUnitInformation[VtdIndex].CapReg.Bits.ND * 2 + 4)) - 1);
ExtContextEntry->Bits.Present = 1;
- } else {
+ } else if (ContextEntry != NULL) {
ContextEntry->Bits.SecondLevelPageTranslationPointer = Pt;
ContextEntry->Bits.DomainIdentifier = ((1 << (UINT8)((UINTN)mVtdUnitInformation[VtdIndex].CapReg.Bits.ND * 2 + 4)) - 1);
ContextEntry->Bits.Present = 1;
--
2.12.0.windows.1
next prev parent reply other threads:[~2017-08-01 4:29 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-01 4:32 [PATCH 0/2] IntelSiliconPkg/IntelVTdDxe: Code refinements Hao Wu
2017-08-01 4:32 ` [PATCH 1/2] IntelSiliconPkg/IntelVTdDxe: Fix typo for VTd IOTLB domain ID Hao Wu
2017-08-01 4:56 ` Yao, Jiewen
2017-08-01 4:32 ` Hao Wu [this message]
2017-08-01 4:56 ` [PATCH 2/2] IntelSiliconPkg/IntelVTdDxe: Add explicit NULL pointer checks Yao, Jiewen
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