From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Campbell <ian.campbell@citrix.com>
Subject: Re: Question about mapping between domains
Date: Tue, 14 Jul 2015 16:49:32 +0100
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To: Oleksandr Dmytryshyn <oleksandr.dmytryshyn@globallogic.com>
Cc: Keir Fraser <keir@xen.org>, Ian Jackson <ian.jackson@eu.citrix.com>, Tim Deegan <tim@xen.org>, xen-devel <xen-devel@lists.xen.org>, Stefano Stabellini <stefano.stabellini@citrix.com>, Jan Beulich <jbeulich@suse.com>
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On Tue, 2015-07-14 at 18:31 +0300, Oleksandr Dmytryshyn wrote:
> > There is an additional quirk for a 1:1 mapped dom0 which is that we
> > don't actually decrease reservation when ballooning, but keep the 1:1
> > mfn in anticipation of ballooning it back in later.
> Could You please tell me a bit more information about this quirk. How this quirk
> can be enabled?

It's enabled by the same dom0_11_mapping which the dom0 domain_builder
uses, look for uses of is_domain_direct_mapped, in particular the ones
in xen/common/memory.c.

Ian.