From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: Baffled by multipage_allocation_permitted()
Date: Tue, 16 Jun 2009 10:41:46 +0100
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To: Jan Beulich <JBeulich@novell.com>, Dave McCracken <dcm@mccr.org>
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On 16/06/2009 10:19, "Jan Beulich" <JBeulich@novell.com> wrote:

>> We can just get rid of it I think. There are arguably worse other things we
>> already allow, like any guest can allocate low memory by specifying a small
>> value of XENMEMF_address_bits().
> 
> Wouldn't it be better to tighten things rather than relaxing them?

It'll need policy to be expressed and pushed down from the toolstack
somehow. Noone's really thought about it too much. In this case I think I
will keep the checking macro actually, and simply disallow allocations
greater than order-9 (2MB superpage) unless the domain has direct hardware
access capability.

 -- Keir