- Establish the pde for the thread structure within the process 
  before a switch to the process occurs.

reactos/ntoskrnl/ke

diff -u -r1.51 -r1.52
--- kthread.c	21 Aug 2004 21:09:39 -0000	1.51
+++ kthread.c	27 Aug 2004 10:24:04 -0000	1.52
@@ -16,7 +16,7 @@

  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */

-/* $Id: kthread.c,v 1.51 2004/08/21 21:09:39 tamlin Exp $

+/* $Id: kthread.c,v 1.52 2004/08/27 10:24:04 hbirr Exp $

  *
  * FILE:            ntoskrnl/ke/kthread.c
  * PURPOSE:         Microkernel thread support

@@ -188,8 +188,16 @@

       Thread->StackLimit = (ULONG)&init_stack;
       Thread->KernelStack = (PVOID)&init_stack_top;
     }

+
+  /* 
+   * Establish the pde's for the new stack and the thread structure within the 
+   * address space of the new process. They are accessed while taskswitching or
+   * while handling page faults. At this point it isn't possible to call the 
+   * page fault handler for the missing pde's. 
+   */

   
   MmUpdatePageDir((PEPROCESS)Process, (PVOID)Thread->StackLimit, MM_STACK_SIZE);

+  MmUpdatePageDir((PEPROCESS)Process, (PVOID)Thread, sizeof(ETHREAD));

 
   /* 
    * The Native API function will initialize the TEB field later 

reactos/ntoskrnl/ke

diff -u -r1.25 -r1.26
--- process.c	21 Aug 2004 21:19:06 -0000	1.25
+++ process.c	27 Aug 2004 10:24:04 -0000	1.26
@@ -16,7 +16,7 @@

  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */

-/* $Id: process.c,v 1.25 2004/08/21 21:19:06 tamlin Exp $

+/* $Id: process.c,v 1.26 2004/08/27 10:24:04 hbirr Exp $

  *
  * PROJECT:         ReactOS kernel
  * FILE:            ntoskrnl/ke/process.c

@@ -55,16 +55,17 @@

 	KEBUGCHECK(INVALID_PROCESS_ATTACH_ATTEMPT);
      }
    

-   /* The stack of the current process may be located in a page which is
-      not present in the page directory of the process we're attaching to.
-      That would lead to a page fault when this function returns. However,
-      since the processor can't call the page fault handler 'cause it can't
-      push EIP on the stack, this will show up as a stack fault which will
-      crash the entire system.

+   /* The stack and the thread structure of the current process may be 
+      located in a page which is not present in the page directory of 
+      the process we're attaching to. That would lead to a page fault 
+      when this function returns. However, since the processor can't 
+      call the page fault handler 'cause it can't push EIP on the stack, 
+      this will show up as a stack fault which will crash the entire system.

       To prevent this, make sure the page directory of the process we're
       attaching to is up-to-date. */
 
    MmUpdatePageDir(Process, (PVOID)CurrentThread->Tcb.StackLimit, MM_STACK_SIZE);

+   MmUpdatePageDir(Process, (PVOID)CurrentThread, sizeof(ETHREAD));

 
    KeRaiseIrql(DISPATCH_LEVEL, &oldlvl);