From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: Re: [Xen-devel] [PATCH net-next v3 1/9] xen-netback: Introduce TX
 grant map definitions
Date: Thu, 9 Jan 2014 18:23:25 +0000
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Cc: Wei Liu <wei.liu2@citrix.com>, <jonathan.davies@citrix.com>,
	Ian Campbell <ian.campbell@citrix.com>,
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To: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
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On 09/01/14 18:09, Stefano Stabellini wrote:
> 
> I agree, but I think that we have different views on the use case.
> To me the m2p_override use case is "everywhere an mfn_to_pfn translation
> is required", that unfortunately is potentially everywhere at this time.

mfn_to_pfn() cannot be made to work correctly with foreign MFNs.  It's a
fundamentally unsolvable problem.

IMO, the only sensible use of the m2p_override is to cause mfn_to_pfn()
to BUG() if a foreign MFN is used.

David