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Re: Linux i386 clone(): %ebx 'frobbing' ?
"Ahmed S. Darwish" <darwish.07@gmail.com> writes:
> Hi Andreas,
>
> On Fri, Feb 15, 2008, Andreas Schwab wrote:
>> "Ahmed S. Darwish" <darwish.07@gmail.com> writes:
>>
>> > I don't understand how the `fn' argument reached the child thread
>> > in the %ebx register. It's said in the comment that `fn' will be
>> > popped to child 'in the ebx frobbing below'. But what does that mean ?
>>
>> See "popl %ebx" after "int $0x80".
>>
>
> I hope I'm not misreading something obvious, but I can't find
> the code where FUNC(%esp) is stored in %ebx before %ebx value
> got pushed in the stack (and restored in above 'popl' statement).
It is stored in the new stack for the child, as explained in the
comment. The parent has a different stack.
Andreas.
--
Andreas Schwab, SuSE Labs, schwab@suse.de
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