From: 陳韋任 <chenwj@iis.sinica.edu.tw>
To: Paul Brook <paul@codesourcery.com>
Cc: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] How to follow a child process created in the guest OS?
Date: Sat, 11 Feb 2012 07:54:42 +0800 [thread overview]
Message-ID: <20120210235442.GA99267@cs.nctu.edu.tw> (raw)
In-Reply-To: <201202102348.06492.paul@codesourcery.com>
On Fri, Feb 10, 2012 at 11:48:05PM +0000, Paul Brook wrote:
> > I am running this tiny OS on QEMU then using GDB to connect it.
> >
> > I want to follow task 1 after the forking, but it seems that GDB
> > stick with task 0 and cannot follow task 1 even I do `set follow-fork-mode
> > child`.
>
> You have exactly one CPU. That's what the qemu GDB stub exposes. Multiple
> processes are an illusion created by your operating system. It is not
> something qemu knows or cares about.
>
> In most cases if you want to do debugging within that OS created illusion (aka
> a userspace process) then you probably don't want to be using a hardware debug
> probe (i.e. the qemu gdb stub) at all. Instead you want to be using the debug
> facilities provided by your operating system. On linux this would be ptrace,
> probably via gdbserver.
I see. Thanks.
Regards,
chenwj
--
Wei-Ren Chen (陳韋任)
Computer Systems Lab, Institute of Information Science,
Academia Sinica, Taiwan (R.O.C.)
Tel:886-2-2788-3799 #1667
Homepage: http://people.cs.nctu.edu.tw/~chenwj
next prev parent reply other threads:[~2012-02-10 23:54 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-09 10:33 [Qemu-devel] How to follow a child process created in the guest OS? 陳韋任
2012-02-10 8:14 ` Stefan Hajnoczi
2012-02-10 10:26 ` 陳韋任
2012-02-10 23:48 ` Paul Brook
2012-02-10 23:54 ` 陳韋任 [this message]
2012-02-11 0:42 ` Andreas Färber
2012-02-11 0:50 ` malc
2012-02-12 3:00 ` Wei Yang
2012-02-13 10:49 ` Stefan Hajnoczi
2012-02-10 9:24 ` Max Filippov
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