[ion] 20918: - Fix a bad bug in the system call handler and interrupt/trap exit code which was causing a jump to the incorrect epilogue if V86 mode was detected.

- Fix a bad bug in the system call handler and interrupt/trap exit code
which was causing a jump to the incorrect epilogue if V86 mode was
detected.
- Replaced most of the trap prolog code by the KiDebugService entry trap
code from syscall.S. Eventually, after remaining bugs are fixed, the
code will be shared across all traps and not duplicated anymore. (For
documnetation's sake, changing the prolog has the following effects: DR
registers are not saved anymore (they will be later), DS/ES are set to
RPL3 DATA, not RPL0 DATA, GS is not touched (it shoudl be 0, not
RPL0_DATA). PreviousMode is not touched at all, the Debug Trap Frame
header is properly setup).
Modified: trunk/reactos/ntoskrnl/ke/i386/syscall.S
Modified: trunk/reactos/ntoskrnl/ke/i386/trap.s
  _____  

Modified: trunk/reactos/ntoskrnl/ke/i386/syscall.S
--- trunk/reactos/ntoskrnl/ke/i386/syscall.S	2006-01-16 17:17:49 UTC
(rev 20917)
+++ trunk/reactos/ntoskrnl/ke/i386/syscall.S	2006-01-16 19:32:55 UTC
(rev 20918)
@@ -742,7 +742,7 @@

     pop edx
     pop ecx
     pop eax
-    jmp V86_Exit_Return
+    jmp V86_Exit_Return2
 
 EditedFrame2:
     /* Restore real CS value */
@@ -887,6 +887,7 @@
     /* Exit through common routine */
     jmp Kei386EoiHelper@0
 
+.globl Kei386EoiHelper@0
 Kei386EoiHelper@0:
 
     /* Disable interrupts */
@@ -992,7 +993,7 @@
     pop edx
     pop ecx
     pop eax
-    jmp V86_Exit_Return
+    jmp V86_Exit_Return3
 
 EditedFrame3:
     /* Restore real CS value */
  _____  

Modified: trunk/reactos/ntoskrnl/ke/i386/trap.s
--- trunk/reactos/ntoskrnl/ke/i386/trap.s	2006-01-16 17:17:49 UTC
(rev 20917)
+++ trunk/reactos/ntoskrnl/ke/i386/trap.s	2006-01-16 19:32:55 UTC
(rev 20918)
@@ -15,6 +15,12 @@

 #define KernelMode 0
 #define UserMode 1
 
+/* NOTES:
+ * The epilog will be replaced by a call to Ki386EoiHelper when bugs
are fixed.
+ * The prologue is currently a duplication of the trap enter code in
KiDebugService.
+ * It will be made a macro and shared later.
+ */
+
 /* FUNCTIONS
*****************************************************************/
 
 /*
@@ -69,79 +75,62 @@
 	pushl	%edi
 	pushl	%fs
 
-	/* Make room for the previous mode and the exception list */
-	subl	$8, %esp
+.intel_syntax noprefix
+    /* Load the PCR selector into fs */
+    mov edi, KGDT_R0_PCR
+    mov fs, di
 
-	/* Save other registers */	
-	pushl	%eax
-	pushl	%ecx
-	pushl	%edx
-	pushl	%ds
-	pushl	%es
-	pushl	%gs
-	movl	%dr7, %eax
-	pushl	%eax		/* Dr7 */
-	/* Clear all breakpoint enables in dr7. */
-	andl	$0xFFFF0000, %eax
-	movl	%eax, %dr7
-	movl	%dr6, %eax
-	pushl	%eax		/* Dr6 */
-	movl	%dr3, %eax
-	pushl	%eax		/* Dr3 */
-	movl	%dr2, %eax
-	pushl	%eax		/* Dr2 */
-	movl	%dr1, %eax
-	pushl	%eax		/* Dr1 */
-	movl	%dr0, %eax
-	pushl	%eax		/* Dr0 */
-	leal    0x64(%esp), %eax
-	pushl	%eax		/* XXX: TempESP */
-	pushl	%ss		/* XXX: TempSS */
-	pushl	$0		/* XXX: DebugPointer */
-	pushl	$0		/* XXX: DebugArgMark */
-	movl    0x60(%esp), %eax
-	pushl	%eax		/* XXX: DebugEIP */
-	pushl	%ebp		/* XXX: DebugEBP */	
-	
-	/* Load the segment registers */
-	movl	$KGDT_R0_DATA, %eax
-	movl	%eax, %ds
-	movl	%eax, %es
-	movl	%eax, %gs
-	
-	/* save the trap frame */
-	movl	%esp, %ebp		
-	
-	/* Load the PCR selector into fs */
-	movl	$KGDT_R0_PCR, %eax
-	movl	%eax, %fs
+    /* Push exception list and previous mode (invalid) */
+    push fs:[KPCR_EXCEPTION_LIST]
+    push -1
 
-	/* Save the old exception list */
-	movl    %fs:KPCR_EXCEPTION_LIST, %eax
-	movl	%eax, KTRAP_FRAME_EXCEPTION_LIST(%ebp)
-	
-	/* Get a pointer to the current thread */
-	movl    %fs:KPCR_CURRENT_THREAD, %edi
+    /* Push volatiles and segments */
+    push eax
+    push ecx
+    push edx
+    push ds
+    push es
+    push gs
 
-	/* The current thread may be NULL early in the boot process */
-	cmpl	$0, %edi
-	je	.L4
-		
-	/* Save the old previous mode */
-	movl    $0, %eax
-	movb    KTHREAD_PREVIOUS_MODE(%edi), %al
-	movl	%eax, KTRAP_FRAME_PREVIOUS_MODE(%ebp)
-	
-        /* Set the new previous mode based on the saved CS selector */
-	movl	 KTRAP_FRAME_CS(%ebp), %eax
-	andl     $0x0000FFFF, %eax
+    /* Set the R3 data segment */
+    mov ax, KGDT_R3_DATA + RPL_MASK
 
-	/* Save the old trap frame. */
-	movl	KTHREAD_TRAP_FRAME(%edi), %edx
-	pushl	%edx
-	
-	/* Save a pointer to the trap frame in the current KTHREAD */
-	movl	%ebp, KTHREAD_TRAP_FRAME(%edi)
+    /* Skip debug registers and debug stuff */
+    sub esp, 0x30
+
+    /* Load the segment registers */
+    mov ds, ax
+    mov es, ax
+
+    /* Set up frame */
+    mov ebp, esp
+
+    /* Check if this was from V86 Mode */
+    test dword ptr [ebp+KTRAP_FRAME_EFLAGS], X86_EFLAGS_VM
+    //jnz V86_kids
+
+    /* Get current thread */
+    mov ecx, [fs:KPCR_CURRENT_THREAD]
+    cld
+
+    /* Flush DR7 */
+    and dword ptr [ebp+KTRAP_FRAME_DR7], 0
+
+    /* Check if the thread was being debugged */
+    //test byte ptr [ecx+KTHREAD_DEBUG_ACTIVE], 0xFF
+    //jnz Dr_kids
+
+    /* Get the Debug Trap Frame EBP/EIP */
+    mov ecx, [ebp+KTRAP_FRAME_EBP]
+    mov edi, [ebp+KTRAP_FRAME_EIP]
+
+    /* Write the debug data */
+    mov [ebp+KTRAP_FRAME_DEBUGPOINTER], edx
+    mov dword ptr [ebp+KTRAP_FRAME_DEBUGARGMARK], 0xBADB0D00
+    mov [ebp+KTRAP_FRAME_DEBUGEBP], ecx
+    mov [ebp+KTRAP_FRAME_DEBUGEIP], edi
+.att_syntax
+
 .L6:	
 	
 	/* Call the C exception handler */
@@ -150,25 +139,9 @@
 	call	*%ebx
 	addl	$8, %esp
 
-	/* Get a pointer to the current thread */
-        movl	%fs:KPCR_CURRENT_THREAD, %esi
-        
-        /* Restore the old trap frame pointer */
-	popl	%ebx
-	cmpl	$0, %esi
-	je	_KiTrapEpilog
-	movl	%ebx, KTHREAD_TRAP_FRAME(%esi)
-
 	/* Return to the caller */
 	jmp	_KiTrapEpilog
 
-	/* Handle the no-thread case out of line */
-.L4:
-	movl	$0, %eax	/* previous mode */
-	movl	%eax, KTRAP_FRAME_PREVIOUS_MODE(%ebp)
-	pushl	%eax		/* old trap frame */
-	jmp	.L6	
-	
 .globl _KiTrap0
 _KiTrap0:
 	/* No error code */