From b3f049be4fb4e16009c2275eac6dba1d73ea5a66 Mon Sep 17 00:00:00 2001
From: Alex Ionescu <aionescu@gmail.com>
Date: Sun, 17 Oct 2004 03:43:26 +0000
Subject: [PATCH] KeStackAttach: Acquire lock before getting thread

svn path=/trunk/; revision=11305
---
 reactos/ntoskrnl/ke/i386/kernel.c | 20 +++++++++++---------
 reactos/ntoskrnl/ke/process.c     |  4 ++--
 2 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/reactos/ntoskrnl/ke/i386/kernel.c b/reactos/ntoskrnl/ke/i386/kernel.c
index f4ca505e7b1..c2865a6f8f6 100644
--- a/reactos/ntoskrnl/ke/i386/kernel.c
+++ b/reactos/ntoskrnl/ke/i386/kernel.c
@@ -134,30 +134,31 @@ KePrepareForApplicationProcessorInit(ULONG Id)
 VOID
 KeApplicationProcessorInit(VOID)
 {
-  PKPCR KPCR;
+  PKPCR Pcr;
   ULONG Offset;
 
   /*
    * Create a PCR for this processor
    */
   Offset = InterlockedIncrement((LONG *)&PcrsAllocated) - 1;
-  KPCR = (PKPCR)(KPCR_BASE + (Offset * PAGE_SIZE));
-  MmCreateVirtualMappingForKernel((PVOID)KPCR,
+  Pcr = (PKPCR)(KPCR_BASE + (Offset * PAGE_SIZE));
+  MmCreateVirtualMappingForKernel((PVOID)Pcr,
 				  PAGE_READWRITE,
 				  &PcrPages[Offset],
 				  1);
-  memset(KPCR, 0, PAGE_SIZE);
-  KPCR->ProcessorNumber = (UCHAR)Offset;
-  KPCR->Self = KPCR;
-  KPCR->Irql = HIGH_LEVEL;
+  memset(Pcr, 0, PAGE_SIZE);
+  Pcr->ProcessorNumber = (UCHAR)Offset;
+  Pcr->Self = Pcr;
+  Pcr->Tib.Self = &Pcr->Tib;
+  Pcr->Irql = HIGH_LEVEL;
 
   /* Mark the end of the exception handler list */
-  KPCR->Tib.ExceptionList = (PVOID)-1;
+  Pcr->Tib.ExceptionList = (PVOID)-1;
 
   /*
    * Initialize the GDT
    */
-  KiInitializeGdt(KPCR);
+  KiInitializeGdt(Pcr);
   
   /*
    * It is now safe to process interrupts
@@ -215,6 +216,7 @@ KeInit1(PCHAR CommandLine, PULONG LastKernelAddress)
    KPCR = (PKPCR)KPCR_BASE;
    memset(KPCR, 0, PAGE_SIZE);
    KPCR->Self = (PKPCR)KPCR_BASE;
+   KPCR->Tib.Self = (PKPCR_TIB)KPCR_BASE;
    KPCR->Irql = HIGH_LEVEL;
    KPCR->GDT = KiBootGdt;
    KPCR->IDT = (PUSHORT)KiIdt;
diff --git a/reactos/ntoskrnl/ke/process.c b/reactos/ntoskrnl/ke/process.c
index 064d6dbc2b6..fbd28bcc13b 100644
--- a/reactos/ntoskrnl/ke/process.c
+++ b/reactos/ntoskrnl/ke/process.c
@@ -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 1.29 2004/10/13 22:27:03 ion Exp $
+/* $Id: process.c,v 1.30 2004/10/17 03:43:26 ion Exp $
  *
  * PROJECT:         ReactOS kernel
  * FILE:            ntoskrnl/ke/process.c
@@ -138,8 +138,8 @@ KeStackAttachProcess (
 	KIRQL OldIrql;
 	PKTHREAD Thread;
 	
-	Thread = KeGetCurrentThread();
 	OldIrql = KeAcquireDispatcherDatabaseLock();
+	Thread = KeGetCurrentThread();
 	
 	/* Crash system if DPC is being executed! */
 	if (KeIsExecutingDpc()) {