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Subject: Re: [Qemu-devel] QEMU timing requirements
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To: qemu-devel@nongnu.org

On 06/25/2011 10:02 PM, Mulyadi Santosa wrote:
> On Sat, Jun 25, 2011 at 23:28, felix.matenaar@rwth-aachen
> <felix.matenaar@rwth-aachen.de>  wrote:
>> No. What I do is using gen_helper_ to compile hooks into call/ret/jmp and
>> memory access. The Heuristics can then hook the events so calculation is
>> done during the execution of a basic block. I thought that it could be
>> possible that Qemu sets a timeout for BBL execution to prevent CPU
>> monopolization by e.g. a long sequence of rep. That would make sense because
>> my heuristics calculation time falls into the BBL execution time for Qemu.
>> Does anyone know more about that?
> perhaps your heuristics code somehow coincide with the timer alarm
> (PIT, HPET etc) emulation in Qemu....and somewhere your code is not
> reentrant.....
>

Think I found the problem. It was a bug in my code and because of some 
weird circumstances, backtrace and addresses seemed to be a segfault in 
a BBL.