1 files changed, 9 insertions, 4 deletions

diff --git a/Nt32Pkg/TimerDxe/Timer.c b/Nt32Pkg/TimerDxe/Timer.c
index 97ea73345b..d9944414cf 100644
--- a/Nt32Pkg/TimerDxe/Timer.c
+++ b/Nt32Pkg/TimerDxe/Timer.c
@@ -115,9 +115,12 @@ Returns:
   if (!mCancelTimerThread) {

   

     //

-    //  Suspend the main thread until we are done

+    // Suspend the main thread until we are done.

+    // Enter the critical section before suspending

+    // and leave the critical section after resuming

+    // to avoid deadlock between main and timer thread.

     //

-

+    gWinNt->EnterCriticalSection (&mNtCriticalSection);

     gWinNt->SuspendThread (mNtMainThreadHandle);

 

     //

@@ -127,6 +130,7 @@ Returns:
     //

     if (mCancelTimerThread) {

       gWinNt->ResumeThread (mNtMainThreadHandle);

+      gWinNt->LeaveCriticalSection (&mNtCriticalSection);

       gWinNt->timeKillEvent (wTimerID);

       mMMTimerThreadID = 0;

       return ;

@@ -138,6 +142,7 @@ Returns:
       //  Resume the main thread

       //

       gWinNt->ResumeThread (mNtMainThreadHandle);

+      gWinNt->LeaveCriticalSection (&mNtCriticalSection);

 

       //

       //  Wait for interrupts to be enabled.

@@ -151,6 +156,7 @@ Returns:
       //

       //  Suspend the main thread until we are done

       //

+      gWinNt->EnterCriticalSection (&mNtCriticalSection);

       gWinNt->SuspendThread (mNtMainThreadHandle);

       mCpu->GetInterruptState (mCpu, &InterruptState);

     }

@@ -174,9 +180,7 @@ Returns:
       //  expired since the last call is 10,000 times the number

       //  of ms.  (or 100ns units)

       //

-      gWinNt->EnterCriticalSection (&mNtCriticalSection);

       CallbackFunction = mTimerNotifyFunction;

-      gWinNt->LeaveCriticalSection (&mNtCriticalSection);

 

       //

       // Only invoke the callback function if a Non-NULL handler has been

@@ -194,6 +198,7 @@ Returns:
     //  Resume the main thread

     //

     gWinNt->ResumeThread (mNtMainThreadHandle);

+    gWinNt->LeaveCriticalSection (&mNtCriticalSection);

   } else {

     gWinNt->timeKillEvent (wTimerID);

     mMMTimerThreadID = 0;