From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir@xensource.com>
Subject: Re: memsize for HVM save/restore
Date: Tue, 27 Mar 2007 16:52:28 +0100
Message-ID: <C22EFC4C.C4D6%keir@xensource.com>
References: <20070327154226.GA21485@edwin-srv.sh.intel.com>
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To: "Zhai, Edwin" <edwin.zhai@intel.com>
Cc: xen-devel@lists.xensource.com, Ewan Mellor <ewan@xensource.com>
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On 27/3/07 16:42, "Zhai, Edwin" <edwin.zhai@intel.com> wrote:

> 2 concerns:
> 1. xc_hvm_build use SCRATCH_PFN(0xFFFFF) to map shared_info, which would
> overwrite the true max_gpfn. So shall we add check in set_p2m_entry for this?

It'll mean the minimum bitmap size is 128kB. Big deal. If we find places
where this *does* matter, I think we should add a better hypercall to
actually indicate which chunks of the physmap space are in use (e.g., return
a bitmap, with one bit per megabyte of pseudophys space -- bit set if any
page in that megabyte chunk is populated or has ever been populated).

> 2. If qemu get the memsize from XENMEM_maximum_gpfn when restore, it's better
> to 
> do the same thing when create, i.e. remove the '-m' qemu command line.

I fully agree!

 -- Keir