From 75b046c3d4aca166de580f5b80c42a14fcbd60eb Mon Sep 17 00:00:00 2001
From: vanjeff <vanjeff@6f19259b-4bc3-4df7-8a09-765794883524>
Date: Fri, 1 Aug 2008 08:10:49 +0000
Subject: [PATCH] Using Spin lock instead of using RaiseTpl() to prevent
 UnloadImage() re-entrance.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@5600 6f19259b-4bc3-4df7-8a09-765794883524
---
 MdeModulePkg/Core/Dxe/Image/Image.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/MdeModulePkg/Core/Dxe/Image/Image.c b/MdeModulePkg/Core/Dxe/Image/Image.c
index dbb662519f..477eaa3417 100644
--- a/MdeModulePkg/Core/Dxe/Image/Image.c
+++ b/MdeModulePkg/Core/Dxe/Image/Image.c
@@ -17,6 +17,8 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 // Module Globals
 //
 
+SPIN_LOCK                  mUnloadImageLock;
+
 LOADED_IMAGE_PRIVATE_DATA  *mCurrentImage = NULL;
 
 LOAD_PE32_IMAGE_PRIVATE_DATA  mLoadPe32PrivateData = {
@@ -137,6 +139,11 @@ CoreInitializeImageServices (
 
   mCurrentImage = Image;
 
+  //
+  // Initialize spin lock
+  //
+  InitializeSpinLock (&mUnloadImageLock);
+
   //
   // Fill in DXE globals
   //
@@ -1362,13 +1369,14 @@ CoreUnloadImage (
 {
   EFI_STATUS                 Status;
   LOADED_IMAGE_PRIVATE_DATA  *Image;
-  EFI_TPL                    OldTpl;
 
   //
   // Prevent possible reentrance to this function
   // for the same ImageHandle
   //
-  OldTpl = CoreRaiseTpl (TPL_NOTIFY);
+  if (!AcquireSpinLockOrFail (&mUnloadImageLock)) {
+    return EFI_UNSUPPORTED;
+  }
 
   Image = CoreLoadedImageInfo (ImageHandle);
   if (Image == NULL ) {
@@ -1404,7 +1412,7 @@ CoreUnloadImage (
   }
 
 Done:
-  CoreRestoreTpl (OldTpl);
+  ReleaseSpinLock (&mUnloadImageLock);
   return Status;
 }
 
-- 
2.39.2