SourceLevelDebugPkg: Avoid to re-init IDT table again at SMI entry

Current SmmDebugAgentLib will initialize IDT table to support source debugging
at each time SMI entry on SMM BSP. Actually, we only need to initialize IDT
table at first time SMI entry.

Add one flag to avoid re-initializing IDT table.

Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>

1 files changed, 9 insertions, 1 deletions

diff --git a/SourceLevelDebugPkg/Library/DebugAgent/SmmDebugAgent/SmmDebugAgentLib.c b/SourceLevelDebugPkg/Library/DebugAgent/SmmDebugAgent/SmmDebugAgentLib.c
index 701c4be0d0..6216142dba 100644
--- a/SourceLevelDebugPkg/Library/DebugAgent/SmmDebugAgent/SmmDebugAgentLib.c
+++ b/SourceLevelDebugPkg/Library/DebugAgent/SmmDebugAgent/SmmDebugAgentLib.c
@@ -19,6 +19,7 @@ DEBUG_AGENT_MAILBOX         mLocalMailbox;
 UINTN                       mSavedDebugRegisters[6];

 IA32_IDT_GATE_DESCRIPTOR    mIdtEntryTable[33];

 BOOLEAN                     mSkipBreakpoint = FALSE;

+BOOLEAN                     mSmmDebugIdtInitFlag = FALSE;

 

 CHAR8 mWarningMsgIgnoreSmmEntryBreak[] = "Ignore smmentrybreak setting for SMI issued during DXE debugging!\r\n";

 

@@ -276,7 +277,14 @@ InitializeDebugAgent (
 

   case DEBUG_AGENT_INIT_ENTER_SMI:

     SaveDebugRegister ();

-    InitializeDebugIdt ();

+    if (!mSmmDebugIdtInitFlag) {

+      //

+      // We only need to initialize Debug IDT table at first SMI entry

+      // after SMM relocation.

+      //

+      InitializeDebugIdt ();

+      mSmmDebugIdtInitFlag = TRUE;

+    }

     //

     // Check if CPU APIC Timer is working, otherwise initialize it.

     //