From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: Re: [PATCH 3/3] x86/xen: optimize get_phys_to_machine()
Date: Wed, 7 Jan 2015 15:24:18 +0000
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On 07/01/15 15:18, Juergen Gross wrote:
> On 01/07/2015 03:47 PM, David Vrabel wrote:
>> The page table walk is only needed to distinguish between identity and
>> missing, both of which have INVALID_P2M_ENTRY.
> 
> As get_phys_to_machine is called by __pfn_to_mfn() only which already
> checks for mfn == INVALID_P2M_ENTRY this optimization will have an
> effect only in the early boot case with pfn >= xen_p2m_size.
> 
> I doubt this is necessary.

Doh. Now I remember suggesting this "optimization" before and getting
the same answer from you.

I'll drop this patch.

David