page fault handling in Xen

[jeet <jeet_sat12@yahoo.co.in>]

Hi All,

I am trying to understand Shadow page fault handling in Xen for x86_64 in Intel VT-x

As per my understanding when guest can update it own page table without causing VM exit in xen

when some process requires some memory (pages) this will cause page fault and control goes to guest OS
the guest then allocate page from its own psuedo address space and make entries in guest page table which contain
mapping of virtual to psuedo physical memory and

But when actual write occurs to that page, page fault occurs which will cause vm exit in xen.

Xen then will update the page mfn in shadow page table and return control back to guest by vn entry.

Is this understanding it correct? so there would be only one vn exit/entry?

please do reply back 

Thanks in advance

Jeet




		
__________________________________________________________
Yahoo! India Answers: Share what you know. Learn something new
http://in.answers.yahoo.com/