diff --git a/SourceLevelDebugPkg/Library/DebugAgent/SecPeiDebugAgent/SecPeiDebugAgentLib.c b/SourceLevelDebugPkg/Library/DebugAgent/SecPeiDebugAgent/SecPeiDebugAgentLib.c
index fba41eecb7..20b6a370d6 100644
--- a/SourceLevelDebugPkg/Library/DebugAgent/SecPeiDebugAgent/SecPeiDebugAgentLib.c
+++ b/SourceLevelDebugPkg/Library/DebugAgent/SecPeiDebugAgent/SecPeiDebugAgentLib.c
@@ -657,7 +657,7 @@ InitializeDebugAgentPhase2 (
   MailboxLocation = GetLocationSavedMailboxPointerInIdtEntry ();
   Mailbox = (DEBUG_AGENT_MAILBOX *)(UINTN)(*MailboxLocation);
   BufferSize = PcdGet16(PcdDebugPortHandleBufferSize);
-  if (Phase2Context->InitFlag == DEBUG_AGENT_INIT_PEI) {
+  if (Phase2Context->InitFlag == DEBUG_AGENT_INIT_PEI && BufferSize != 0) {
     NewDebugPortHandle = (UINT64)(UINTN)AllocateCopyPool (BufferSize, DebugPortHandle);
   } else {
     NewDebugPortHandle = (UINT64)(UINTN)DebugPortHandle;
diff --git a/SourceLevelDebugPkg/Library/DebugAgent/SmmDebugAgent/SmmDebugAgentLib.c b/SourceLevelDebugPkg/Library/DebugAgent/SmmDebugAgent/SmmDebugAgentLib.c
index 72db534844..4e4e1f536c 100644
--- a/SourceLevelDebugPkg/Library/DebugAgent/SmmDebugAgent/SmmDebugAgentLib.c
+++ b/SourceLevelDebugPkg/Library/DebugAgent/SmmDebugAgent/SmmDebugAgentLib.c
@@ -282,7 +282,7 @@ InitializeDebugAgent (
     //
     GetApicTimerState (NULL, &PeriodicMode, NULL);
     TimerCycle = GetApicTimerInitCount ();
-    if (PeriodicMode != TRUE || TimerCycle == 0) {
+    if (!PeriodicMode || TimerCycle == 0) {
       InitializeDebugTimer (NULL, FALSE);
       DisableApicTimerInterrupt ();
     }