From 88d6fe5cb4c6f43ee09c790a1557eed16e075486 Mon Sep 17 00:00:00 2001
From: Alex Ionescu <aionescu@gmail.com>
Date: Sat, 23 Apr 2005 20:02:39 +0000
Subject: [PATCH] Don't use hack for trap frames anymore, read TempEsp and
 TempSegSs for kernel-mode traps during debugging.

svn path=/trunk/; revision=14790
---
 reactos/ntoskrnl/include/internal/i386/ke.h |  8 ++--
 reactos/ntoskrnl/kdbg/kdb_cli.c             | 15 ++++++-
 reactos/ntoskrnl/ke/i386/trap.s             | 49 ++-------------------
 3 files changed, 21 insertions(+), 51 deletions(-)

diff --git a/reactos/ntoskrnl/include/internal/i386/ke.h b/reactos/ntoskrnl/include/internal/i386/ke.h
index d68d95e8318..89ad399be49 100644
--- a/reactos/ntoskrnl/include/internal/i386/ke.h
+++ b/reactos/ntoskrnl/include/internal/i386/ke.h
@@ -27,8 +27,8 @@
 #define KTRAP_FRAME_DEBUGEIP     (0x4)
 #define KTRAP_FRAME_DEBUGARGMARK (0x8)
 #define KTRAP_FRAME_DEBUGPOINTER (0xC)
-#define KTRAP_FRAME_TEMPCS       (0x10)
-#define KTRAP_FRAME_TEMPEIP      (0x14)
+#define KTRAP_FRAME_TEMPSS       (0x10)
+#define KTRAP_FRAME_TEMPESP      (0x14)
 #define KTRAP_FRAME_DR0          (0x18)
 #define KTRAP_FRAME_DR1          (0x1C)
 #define KTRAP_FRAME_DR2          (0x20)
@@ -117,8 +117,8 @@ typedef struct _KTRAP_FRAME
    PVOID DebugEip;
    PVOID DebugArgMark;
    PVOID DebugPointer;
-   PVOID TempCs;
-   PVOID TempEip;
+   PVOID TempSegSs;
+   PVOID TempEsp;
    ULONG Dr0;
    ULONG Dr1;
    ULONG Dr2;
diff --git a/reactos/ntoskrnl/kdbg/kdb_cli.c b/reactos/ntoskrnl/kdbg/kdb_cli.c
index 4df5a359910..8e5ee748d2d 100644
--- a/reactos/ntoskrnl/kdbg/kdb_cli.c
+++ b/reactos/ntoskrnl/kdbg/kdb_cli.c
@@ -374,6 +374,19 @@ KdbpCmdRegs(ULONG Argc, PCHAR Argv[])
 
    if (Argv[0][0] == 'r') /* regs */
    {
+      ULONG Esp;
+      USHORT Ss;
+      
+      if (!(Tf->Cs & 1))
+      {
+          Esp = (ULONG)Tf->TempEsp;
+          Ss = (USHORT)((ULONG)Tf->TempSegSs & 0xFFFF);
+      }
+      else
+      {
+          Esp = Tf->Esp;
+          Ss = Tf->Ss;
+      }
       KdbpPrint("CS:EIP  0x%04x:0x%08x\n"
                 "SS:ESP  0x%04x:0x%08x\n"
                 "   EAX  0x%08x   EBX  0x%08x\n"
@@ -381,7 +394,7 @@ KdbpCmdRegs(ULONG Argc, PCHAR Argv[])
                 "   ESI  0x%08x   EDI  0x%08x\n"
                 "   EBP  0x%08x\n",
                 Tf->Cs & 0xFFFF, Tf->Eip,
-                Tf->Ss, Tf->Esp,
+                Ss, Esp,
                 Tf->Eax, Tf->Ebx,
                 Tf->Ecx, Tf->Edx,
                 Tf->Esi, Tf->Edi,
diff --git a/reactos/ntoskrnl/ke/i386/trap.s b/reactos/ntoskrnl/ke/i386/trap.s
index ea84c255ed8..3a3e6cbb3e4 100644
--- a/reactos/ntoskrnl/ke/i386/trap.s
+++ b/reactos/ntoskrnl/ke/i386/trap.s
@@ -76,29 +76,6 @@ _KiTrapRet:
 	popl	%edi
 	popl	%esi
 	popl	%ebx
-
-#ifdef KDBG
-        /*
-         * Cleanup the stack which was used to setup a trapframe with SS:ESP when called
-         * from kmode.
-         */
-        movw    0xC(%esp), %bp             /* Get CS from trapframe */
-        cmpw    $KERNEL_CS, %bp
-        jne     0f
-
-        /* Copy EBP, CS:EIP and EFLAGS from the trapframe back onto the top of our stack. */
-        movl    0x00(%esp), %ebp            /* EBP */
-        movl    %ebp, 0x24(%esp)
-        movl    0x08(%esp), %ebp            /* EIP */
-        movl    %ebp, 0x2C(%esp)
-        movl    0x0C(%esp), %ebp            /* CS */
-        movl    %ebp, 0x30(%esp)
-        movl    0x10(%esp), %ebp            /* EFLAGS */
-        movl    %ebp, 0x34(%esp)
-
-        addl    $0x24, %esp
-0:
-#endif /* DBG */
 	popl	%ebp
 	addl	$0x4, %esp  /* Ignore error code */
 		
@@ -106,27 +83,6 @@ _KiTrapRet:
 
 .globl _KiTrapProlog
 _KiTrapProlog:	
-#ifdef KDBG
-        /*
-         * If we were called from kmode we start setting up a new trapframe (with SS:ESP at the end)
-         */
-        movw    0x14(%esp), %bx             /* Get old CS */
-        cmpw    $KERNEL_CS, %bx
-        
-        jne     0f
-
-        leal    0x1C(%esp), %ebp
-        pushl   %ss                          /* Old SS */
-        pushl   %ebp                         /* Old ESP */
-        pushl   0x20(%esp)                   /* Old EFLAGS */
-        pushl   0x20(%esp)                   /* Old CS */
-        pushl   0x20(%esp)                   /* Old EIP */
-        pushl   0x20(%esp)                   /* ErrorCode */
-        pushl   0x20(%esp)                   /* Ebp */
-        pushl   0x20(%esp)                   /* Ebx */
-        pushl   0x20(%esp)                   /* Esi */
-0:
-#endif /* DBG */
 
 	pushl	%edi
 	pushl	%fs
@@ -191,8 +147,9 @@ _KiTrapProlog:
 	pushl	%eax		/* Dr1 */
 	movl	%dr0, %eax
 	pushl	%eax		/* Dr0 */
-	pushl	$0     /* XXX: TempESP */
-	pushl	$0     /* XXX: TempCS */
+    leal    0x64(%esp), %eax
+	pushl	%eax    /* XXX: TempESP */
+	pushl	%ss     /* XXX: TempSS */
 	pushl	$0     /* XXX: DebugPointer */
 	pushl	$0     /* XXX: DebugArgMark */
 	movl    0x60(%esp), %ebx