From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: xen/x86: Question about alloc_domheap_page in pod
	code
Date: Thu, 22 Oct 2015 16:10:16 +0100
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To: Julien Grall <julien.grall@citrix.com>, George Dunlap <george.dunlap@eu.citrix.com>, Jan Beulich <jbeulich@suse.com>
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On 22/10/15 16:04, Julien Grall wrote:
> Hi,
>
> I was looking to the pod code (arch/x86/mm/p2m-pod.c) and noticed that
> the calls to alloc_domheap_page{s,} seems to take wrong parameter:
>
> page = alloc_domheap_pages(d, order, PAGE_ORDER_4K);
>
> p = alloc_domheap_page(d, PAGE_ORDER_4K);
>
> AFAICT the last parameter is the memory flags and not the order so using
> PAGE_ORDER_4K is wrong. Am I right?
>
> I don't know much x86, hence my question before sending a patch to fix it.

You are completely correct.  It is wrong.

It happens to function as PAGE_ORDER_4K is 0, and means "no memflag
restrictions".

~Andrew