From c6af963e8d2eb560b884f2a32d3affffc21c2f14 Mon Sep 17 00:00:00 2001
From: Sebastian Gasiorek <sebastian.gasiorek@reactos.org>
Date: Fri, 10 Mar 2017 16:33:45 +0000
Subject: [PATCH] [NTUSER] Lock before getting DesktopDC. Fixes crash during
 loading DirectX CORE-7733

svn path=/trunk/; revision=74142
---
 reactos/win32ss/user/ntuser/desktop.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/reactos/win32ss/user/ntuser/desktop.c b/reactos/win32ss/user/ntuser/desktop.c
index 368f12e9dab..1107b09cbf9 100644
--- a/reactos/win32ss/user/ntuser/desktop.c
+++ b/reactos/win32ss/user/ntuser/desktop.c
@@ -932,6 +932,8 @@ UserGetDesktopDC(ULONG DcType, BOOL EmptyDC, BOOL ValidatehWnd)
     PWND DesktopObject = 0;
     HDC DesktopHDC = 0;
 
+    UserEnterExclusive();
+
     if (DcType == DC_TYPE_DIRECT)
     {
         DesktopObject = UserGetDesktopWindow();
@@ -943,6 +945,8 @@ UserGetDesktopDC(ULONG DcType, BOOL EmptyDC, BOOL ValidatehWnd)
         DesktopHDC = IntGdiCreateDisplayDC(pMonitor->hDev, DcType, EmptyDC);
     }
 
+    UserLeave();
+
     return DesktopHDC;
 }