From mboxrd@z Thu Jan  1 00:00:00 1970
From: Xinxin Jin <xinxinjin89@gmail.com>
Subject: How does Xen emulate guest's write to its pte ?
Date: Mon, 22 Oct 2012 12:17:28 -0700
Message-ID: <CAJJWZcy6QQvba5RMTyJy4zWi5f8X5hNGpNA6moTvbpy0cJkPUQ@mail.gmail.com>
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Hi all,
I traced Xen's writable page table handler: PV guests' write operation to a
pte will trap to Xen's page fault handler ptwr_do_page_fault() which will
call x86_emulate() to emulate the write.
But  after I print out the pte (which maps faulting virtual address) value,
 I was very surprised to find that, the value does not change before/after
x86_emulation(). This result confuses me: so how does Xen emulate pte write
then ?
Thanks a lot !
-- 
Xinxin

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Hi all,=A0<br clear=3D"all"><div>I traced Xen&#39;s writable page table han=
dler: PV guests&#39; write operation to a pte will trap to Xen&#39;s page f=
ault handler=A0ptwr_do_page_fault() which will call x86_emulate() to emulat=
e the write.=A0</div>
<div>But =A0after I print out the pte (which maps faulting virtual address)=
 value, =A0I was very surprised to find that, the value does not change bef=
ore/after x86_emulation(). This result confuses me: so how does Xen emulate=
 pte write then ?</div>
<div>Thanks a lot !</div>-- <br>Xinxin<br>
<br>

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