From 4334f8a57fc217613b49719e098124fe838f73ec Mon Sep 17 00:00:00 2001 From: Alex Ionescu Date: Mon, 16 Jan 2006 19:32:55 +0000 Subject: [PATCH] - 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). svn path=/trunk/; revision=20918 --- reactos/ntoskrnl/ke/i386/syscall.S | 5 +- reactos/ntoskrnl/ke/i386/trap.s | 143 ++++++++++++----------------- 2 files changed, 61 insertions(+), 87 deletions(-) diff --git a/reactos/ntoskrnl/ke/i386/syscall.S b/reactos/ntoskrnl/ke/i386/syscall.S index 850a3635379..043ffd987b2 100644 --- a/reactos/ntoskrnl/ke/i386/syscall.S +++ b/reactos/ntoskrnl/ke/i386/syscall.S @@ -742,7 +742,7 @@ V86_Exit2: pop edx pop ecx pop eax - jmp V86_Exit_Return + jmp V86_Exit_Return2 EditedFrame2: /* Restore real CS value */ @@ -887,6 +887,7 @@ NotUserMode: /* Exit through common routine */ jmp Kei386EoiHelper@0 +.globl Kei386EoiHelper@0 Kei386EoiHelper@0: /* Disable interrupts */ @@ -992,7 +993,7 @@ V86_Exit3: pop edx pop ecx pop eax - jmp V86_Exit_Return + jmp V86_Exit_Return3 EditedFrame3: /* Restore real CS value */ diff --git a/reactos/ntoskrnl/ke/i386/trap.s b/reactos/ntoskrnl/ke/i386/trap.s index 6df935fb7a2..e73fcf024d4 100644 --- a/reactos/ntoskrnl/ke/i386/trap.s +++ b/reactos/ntoskrnl/ke/i386/trap.s @@ -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 @@ _KiTrapProlog2: 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 + + /* 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 - /* 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) .L6: /* Call the C exception handler */ @@ -150,25 +139,9 @@ _KiTrapProlog2: 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 */