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Date: Sat, 11 Feb 2012 04:50:22 +0400 (MSK)
From: malc <av1474@comtv.ru>
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Subject: Re: [Qemu-devel] How to follow a child process created in the guest
 OS?
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To: =?ISO-8859-15?Q?Andreas_F=E4rber?= <afaerber@suse.de>
Cc: Stefan Hajnoczi <stefanha@gmail.com>, qemu-devel@nongnu.org, =?ISO-2022-JP?Q?=1B$BDDpjG$=1B=28J?= <chenwj@iis.sinica.edu.tw>

On Sat, 11 Feb 2012, Andreas F?rber wrote:

> Am 10.02.2012 11:26, schrieb ???:
> > On Fri, Feb 10, 2012 at 08:14:41AM +0000, Stefan Hajnoczi wrote:
> >> On Thu, Feb 09, 2012 at 06:33:16PM +0800, ??? wrote:
> >>> I am running a tiny OS on QEMU and debugging it with gdbstub. The tiny OS will
> >>> fork process 1, 2, ... and so on. I want to follow the child process, [...]
> >>>
> >>>   Is there a way to do what I'm trying to do? Thanks!
> 
> > ----------------- Tiny OS code -----------------------------
> > void main(void)   /* This really IS void, no error here. */
> > {
> >   /* initialize enviroment */
> > 
> >   sti();
> >   move_to_user_mode();
> >   if (!fork()) {    /* we count on this going ok */
> >     init();         // task 1
> >   }
> > 
> >   for(;;) pause();  // task 0
> > } 
> > ------------------------------------------------------------
> > 
> >   I am running this tiny OS on QEMU then using GDB to connect it.
> > I want to follow task 1 after the forking, [...]
> 
> Since this seems to be your code, if this were PowerPC I'd simply try to
> place via inline assembler a trap instruction first thing inside the

Being hardcore are we? __builtin_trap () is there for a reason.

> init() function. That can easily be caught in gdbstub.
> 
> Depending on what you really want to do, you could always try some
> printf-style output to serial. ;)
> 
> Andreas
> 
> 

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