[hbelusca] 64383: [NTVDM]: Use the 0xCC (int 3) instruction as the memory fill byte.

Author: hbelusca
Date: Sun Sep 28 22:35:05 2014
New Revision: 64383

URL: http://svn.reactos.org/svn/reactos?rev=64383&view=rev
Log:
[NTVDM]: Use the 0xCC (int 3) instruction as the memory fill byte.

Modified:
    trunk/reactos/subsystems/ntvdm/emulator.c

Modified: trunk/reactos/subsystems/ntvdm/emulator.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/subsystems/ntvdm/emulator.…
==============================================================================
--- trunk/reactos/subsystems/ntvdm/emulator.c	[iso-8859-1] (original)
+++ trunk/reactos/subsystems/ntvdm/emulator.c	[iso-8859-1] Sun Sep 28 22:35:05 2014
@@ -549,8 +549,12 @@
         wprintf(L"FATAL: Failed to allocate VDM memory.\n");
         return FALSE;
     }
-    // For diagnostics purposes!!
-    RtlFillMemory(BaseAddress, MAX_ADDRESS, 0xFF);
+    /*
+     * For diagnostics purposes, we fill the memory with INT 0x03 codes
+     * so that if a program wants to execute random code in memory, we can
+     * retrieve the exact CS:IP where the problem happens.
+     */
+    RtlFillMemory(BaseAddress, MAX_ADDRESS, 0xCC);
 
     /* Initialize I/O ports */
     /* Initialize RAM */