Subject: Re: [Xen-devel] [PATCH net-next v3 1/9] xen-netback: Introduce TX grant map definitions

From: David Vrabel <[email-masked]>
Date: Thu, 9 Jan 2014 18:23:25 +0000

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