Re: [patch] M2P/P2M abstraction

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Mon, May 11, 2009 at 10:23:24PM +0200, Jean-Yves Migeon wrote:
> >>I thought (wrongfully maybe) that removing Xen 2 support basically sets  
> >>the requirements on Xen 3.0.2 and up at least, given the new  
> >>functionalities added in -current. I am not sure that PCI passthrough  
> >>works ok with 3.0.1 and below, for example.
> >
> >But you don't have to use the new functionalities to use -current :)
> 
> I agree, that was just an example. We depend on XenSource's willingness 
> to stay compatible with previous Xen's revisions; this is not 
> purely-NetBSD oriented.

XenSource is willing to stay backward-compatible AFAIK. 

> 
> I'd like to know if we are going to have issues by keeping an old API 
> (we are still working with the 3.0 hypercall API right, even with Xen 
> 3.3?), either by seeing functionalities dropped (hypercall page vs int 
> 0x82 for example), or reworked (changes in hypercall API, return codes, 
> or numbers), in the near future.

The API should not change for a given hypercall number. When the API change
a new hypercall is allocated. We have all the informations at runtime to
know which hypercalls are available.

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
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