From mboxrd@z Thu Jan  1 00:00:00 1970
From: Markus Armbruster <armbru@redhat.com>
Subject: Re: [PATCH 00/17] kvm-userspace: Fix and improve guest debugging and x86 debug registers
Date: Mon, 17 Nov 2008 17:44:48 -0500
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References: <20081006091415.095241851@mchn012c.ww002.siemens.net>
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Cc: kvm@vger.kernel.org
To: Jan Kiszka <jan.kiszka@siemens.com>
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In-Reply-To: <20081006091415.095241851@mchn012c.ww002.siemens.net> (Jan Kiszka's message of "Mon\, 06 Oct 2008 11\:14\:15 +0200")
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Jan Kiszka <jan.kiszka@siemens.com> writes:

[...]
> To summarize the contributions of this series (+ its related kernel
> bits):
>  - fully functional guest debugging via gdbstub,
>    including hardware breakpoints and watchpoints
>    (pick up current gdb cvs to have hbreak via remote gdb)
>  - (Almost) unlimited number of standard breakpoints
>  - SMP guest debugging support
>  - x86 debug registers support (makes guest's gdb and kgdb happy)
>
> The patches are in daily use for several moons here and have proven to
> be very helpful for tricky kernel debugging task. Specifically,
> reproducing and then tracking down certain races/deadlocks on SMP boxes
> is far more comfortable with KVM than on "real metal".

Sounds intriguing.  Could you explain briefly what exactly you do to
wire a debuffer to a guest, so dummies like me can give it a whirl?