From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Campbell <Ian.Campbell@citrix.com>
Subject: Re: [PATCH 5/6] xen: arm: add some helpers for
	assessing p2m pte
Date: Tue, 10 Jun 2014 12:46:46 +0100
Message-ID: <1402400806.1250.63.camel@kazak.uk.xensource.com>
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To: Julien Grall <julien.grall@linaro.org>
Cc: stefano.stabellini@eu.citrix.com, tim@xen.org, xen-devel@lists.xen.org
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On Tue, 2014-06-10 at 12:37 +0100, Julien Grall wrote:
> On 06/10/2014 10:57 AM, Ian Campbell wrote:
> >      mask = SECOND_MASK;
> >      second = map_domain_page(pte.p2m.base);
> >      pte = second[second_table_offset(paddr)];
> > -    if ( !pte.p2m.valid || !pte.p2m.table )
> > +    if ( !p2m_table(pte) )
> >          goto done;
> >  
> >      mask = THIRD_MASK;
> > @@ -156,11 +161,11 @@ paddr_t p2m_lookup(struct domain *d, paddr_t paddr, p2m_type_t *t)
> >      pte = third[third_table_offset(paddr)];
> >  
> >      /* This bit must be one in the level 3 entry */
> > -    if ( !pte.p2m.table )
> > +    if ( !p2m_table(pte) )
> >          pte.bits = 0;
> >  
> >  done:
> > -    if ( pte.p2m.valid )
> > +    if ( p2m_valid(pte) )
> 
> Regardless the current check, I think this should be p2m_entry(pte) to
> help code comprehension.
> 
> Indeed, the can only get the address if the pte is pointed to a memory
> block.

Yes, but an L3 PTE has the table bit set, which would make
p2m_entry(pte) false...