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From: Paul Brook <paul@codesourcery.com>
To: qemu-devel@nongnu.org
Cc: Nathan Froyd <froydnj@codesourcery.com>
Subject: Re: [Qemu-devel] [PATCH] fix gdbstub support for multiple threads in usermode, v2
Date: Tue, 2 Jun 2009 21:08:14 +0100	[thread overview]
Message-ID: <200906022108.15384.paul@codesourcery.com> (raw)
In-Reply-To: <1243972429-7972-1-git-send-email-froydnj@codesourcery.com>

On Tuesday 02 June 2009, Nathan Froyd wrote:
> When debugging multi-threaded programs, QEMU's gdb stub would report the
> correct number of threads (the qfThreadInfo and qsThreadInfo packets).
> However, the stub was unable to actually switch between threads (the T
> packet), since it would report every thread except the first as being
> dead.  Furthermore, the stub relied upon cpu_index as a reliable means
> of assigning IDs to the threads.  This was a bad idea; if you have this
> sequence of events:
>
> initial thread created
> new thread #1
> new thread #2
> thread #1 exits
> new thread #3
>
> thread #3 will have the same cpu_index as thread #1, which would confuse
> GDB.

Really? Why doesn't GDB get confused on real machines when the PID wraps?
Is the real bug that we're missing some sort of thread creation/destruction 
event reporting?

Paul

  reply	other threads:[~2009-06-02 20:08 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-06-02 19:53 [Qemu-devel] [PATCH] fix gdbstub support for multiple threads in usermode, v2 Nathan Froyd
2009-06-02 20:08 ` Paul Brook [this message]
2009-06-02 20:46   ` Daniel Jacobowitz
2009-06-02 20:54   ` Nathan Froyd
2009-06-02 21:14     ` Paul Brook
2009-06-02 21:48       ` Nathan Froyd
2009-06-02 21:56         ` Paul Brook
2009-06-16 19:11           ` [Qemu-devel] " Antti P Miettinen
2009-06-16 19:25             ` Paul Brook
2009-06-16 20:02               ` Antti P Miettinen
2009-06-17 16:39               ` Jan Kiszka
2009-06-02 22:44         ` Jan Kiszka

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