Re: [Xen-devel] Sharing Memory between userspace of dom0 and use

To:	Derek.Murray@xxxxxxxxxxxx
Subject:	Re: [Xen-devel] Sharing Memory between userspace of dom0 and userspace of domU
From:	"Mike Sun" <msun@xxxxxxxxxx>
Date:	Tue, 19 Feb 2008 11:16:49 -0500
Cc:	Kareem Dana <kareem.dana@xxxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date:	Tue, 19 Feb 2008 08:17:17 -0800
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Hi --

> > At the moment, yes, the only way to grant access to a page is from the
> > kernel. This is due to the fact that kernel memory corresponds to
> > physical memory, and we don't have to worry about interactions with
> > the swapper, or what happens when the process dies.

>From what I understand of what you've said, are you saying that the
shared memory pages that granted access must always be in physical
memory and cannot be swapped out, even if the guest kernel decided to
for some reason?  Does Xen enforce this in any way, e.g. pinning the
pages somehow?

Thanks,
Mike

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Re: [Xen-devel] Sharing Memory between userspace of dom0 and userspace o