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#GP after big interrupt pause
Posted: Tue Apr 14, 2009 2:37 am
by rezoimnadze
When client calls sysenter procedure, and when we stop interrupts for a big time, after sti instruction General Protection Fault occures.
I think processor wants to make System Timer interrupt and something wrong happens.
How can I debug this incident? what is the reason?
---
Not onley in sysenter procedure. everyware I put this code:
Code: Select all
cli
mov ecx, 0x100000
.Loop:
loop .Loop
sti
mov eax, 0
mov eax, 0
mov eax, 0 ; System Timer Interrupt. Everything is well.
mov eax, 0
mov eax, 0
cli
mov ecx, 0x100000
.Loop1:
loop .Loop1
sti
mov eax, 0
mov eax, 0
mov eax, 0 ; #GP
mov eax, 0
mov eax, 0
In this case:
Code: Select all
cli
mov ecx, 0x1000000 ; I extend loop size.
.Loop:
loop .Loop
sti
mov eax, 0
mov eax, 0 ; #GP
mov eax, 0
mov eax, 0
mov eax, 0
Re: #GP after big interrupt pause
Posted: Tue Apr 14, 2009 6:08 am
by Archil
Is your timer still running while that GPF?
Re: #GP after big interrupt pause
Posted: Tue Apr 14, 2009 7:33 am
by rezoimnadze
No, GPF ISR ends with "jmp $".
Re: #GP after big interrupt pause
Posted: Tue Apr 14, 2009 8:45 am
by Troy Martin
So yes, the timer still runs. JMP $ doesn't stop interrupts, you need CLI and HLT to do that.
The x86 is a
well-documented beast, read the manuals. They help.
Re: #GP after big interrupt pause
Posted: Tue Apr 14, 2009 11:19 pm
by rezoimnadze
Troy Martin wrote:So yes, the timer still runs. JMP $ doesn't stop interrupts, you need CLI and HLT to do that.
The x86 is a
well-documented beast, read the manuals. They help.
I Know, but in interrupt handler (#GP Handler) Interrupt Flag is not set.
I solved this problem by disabling and enabling System Timer and others in PIC, while a pig interrupt pause.
Thank you.
Code: Select all
push ax
cli
push ax
mov ax,0b1111111111111111
out PIC.Data.Port.MasterData,al
mov al,ah
out PIC.Data.Port.SlaveData,al
pop ax
; Large code here.
mov ax,0b1111111111111100
out PIC.Data.Port.MasterData,al
mov al,ah
out PIC.Data.Port.SlaveData,al
pop ax
sti
Re: #GP after big interrupt pause
Posted: Wed Apr 15, 2009 12:21 pm
by earlz
could be possible your timer interrupt is buggy.. it could really be almost anywhere.. you did remap the PIC right?
Re: #GP after big interrupt pause
Posted: Sat Jul 25, 2009 8:19 am
by rezoimnadze
could be possible your timer interrupt is buggy..
Yes, this was. Thank you.
There ware some other "little" problems too.
