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From: "陳韋任 (Wei-Ren Chen)" <chenwj@iis.sinica.edu.tw>
To: Blue Swirl <blauwirbel@gmail.com>
Cc: "Peter Maydell" <peter.maydell@linaro.org>,
	qemu-devel@nongnu.org,
	"陳韋任 (Wei-Ren Chen)" <chenwj@iis.sinica.edu.tw>
Subject: Re: [Qemu-devel] Is it possible to detect guest OS modifying pte inside QEMU?
Date: Thu, 9 Aug 2012 11:15:00 +0800	[thread overview]
Message-ID: <20120809031500.GA71617@cs.nctu.edu.tw> (raw)
In-Reply-To: <CAAu8pHszgjWbiJqambgMvHzbQ4OB1hED_E6+A7Y4UXwx+HNJuA@mail.gmail.com>

Hi Blue,

> >   You mean like what KVM does for shadow page table? I think we should
> > mprotect the QEMU virtual memory which is allocated as a guest page
> > table by the guest OS, right? If so, how do we know what (QEMU) virtual
> > memory we should protect? The other way I was thought of is to see if
> > we can aware some guest code sequence modifying pte, but so far no clue
> > to it.
> 
> See for example notdirty and watch_mem handling in exec.c.

  There are functions st{l,q}_phys_notdirty and notdirty_mem_write, you
mean which one? Sadly, I am not familiar with the memory stuff. Could
you explain a little bit about what notdirty and watch_mem does? Googleing 
doesn't help much...

  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

  reply	other threads:[~2012-08-09  3:15 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-08-08  7:38 [Qemu-devel] Is it possible to detect guest OS modifying pte inside QEMU? 陳韋任 (Wei-Ren Chen)
2012-08-08  8:05 ` Peter Maydell
2012-08-08  8:33   ` 陳韋任 (Wei-Ren Chen)
2012-08-08 19:10     ` Blue Swirl
2012-08-09  3:15       ` 陳韋任 (Wei-Ren Chen) [this message]
2012-08-09 17:05         ` Blue Swirl
2012-08-10  7:42   ` 陳韋任 (Wei-Ren Chen)

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