[Qemu-devel] Re: bug: enter fails if level > 0

[Stefan Kisdaroczi]

Hi,

> Stefan Kisdaroczi <address@hidden> writes:
>
> > ... fixes 2)
> > -       while (level--) {
> > +       while (---level) {
>
> You mean -- not --- right?

Yes i mean -- . Typo in mail only. sorry.

The Problem is Point 3), which I cant fix, but im am 101% sure that this is a 
Bug.
I can easy reproduce/test this Bug with a small Program i made.
I singlestepped it with the System-Debugger on a 'real' System and under qemu.
I checked the entire Stack and the Register esp and ebp before and after each 
call of enter.

My Application crashes with a GP-Fault, because the values on the Stack are 
wrong.
Values > 0 are possibly seldom used, so this bug shows rarely.
However, if a program uses it, it will not work as expected or crash.

This line...
     gen_op_st_T0_A0[ot + s->mem_index]();

... copies T0, but it should copy the value where T0 points to the Stack ( -> 
Stack to Stack copy ).
Now it copies the value of the old ebp, but i should copy the value where the 
old ebp point to (word or dword, depends 16-/32-Bit).

Please help me. I dont think my app is the only one using this instruction.

greetings kisda