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Date: Sat, 5 Apr 2008 10:40:18 +0300
From: "Pekka Enberg" <penberg@cs.helsinki.fi>
To: "Avi Kivity" <avi@qumranet.com>
Subject: Re: mmiotrace bug: recursive probe hit
Cc: "Pekka Paalanen" <pq@iki.fi>, linux-kernel@vger.kernel.org,
       "Ingo Molnar" <mingo@elte.hu>, "Christoph Hellwig" <hch@infradead.org>,
       "Arjan van de Ven" <arjan@infradead.org>,
       "Pavel Roskin" <proski@gnu.org>, "Steven Rostedt" <rostedt@goodmis.org>,
       "Peter Zijlstra" <a.p.zijlstra@chello.nl>, vegard.nossum@gmail.com
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On Sat, Apr 5, 2008 at 10:36 AM, Avi Kivity <avi@qumranet.com> wrote:
> It should not be too difficult to modify x86_emulate.c to do everything
> through a function vector.  However there is a simpler (for you) solution:
> run the driver-to-be-reverse-engineered in a kvm guest, and modify kvm
> userspace to log accesses to mmio regions.  This requires the not-yet-merged
> pci passthrough support.  You can reverse engineer Windows drivers with this
> as well.
>
>  This won't work for kmemcheck smp though.

For kmemcheck, I'd prefer the per-CPU page tables suggested by Ingo.
I'm having hard time understanding why that's a "ugly hack" compared
to using kvm for this...