Re: [Xen-devel] [PATCH 5/8] xen/arm: p2m: Add p2m_get_entry

[Tim Deegan <tim@xxxxxxx>]

B11;rgb:0000/0000/0000At 16:07 +0000 on 05 Dec (1386256032), Ian Campbell wrote:
> On Thu, 2013-12-05 at 15:42 +0000, Julien Grall wrote:
> > Reuse the code of p2m_lookup and add an argument to retrieve the p2m type.
> 
> I'd be inclined to just add the parameter and change the existing
> callers to pass NULL if they don't care about the type.
> 
> The x86 equivalent of this seems to be get_gfn_type which also takes the
> p2m lock, which makes sense because you don't want the entry changing
> under your feet while you do whatever you do with it.
> 
> However, I have a feeling this is related to things like CoW and PoD
> (Tim?)

Yes, though in theory you could have the same sort of trouble with
balloon drivers, device models moving framebuffers, &c. 

Tim.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel