Re: [PATCH] [7/8] CPA: Don't flush caches on CPUs that support self-snoop

Andi Kleen
2008-02-11T15:27:40Z

> > That is exactly the situation in pageattr.c. You're saying the manual
> > is wrong here?
>
> I'm saying that we are not following step 2 (marking the pages not present)

Yes that's true. It's one of the design problems of the intent API that makes
fixing this hard unfortunately.

(intent API assumes that the caller doesn't fully own the page to change, and
if you can't control it 100% it is not possible to unmap it temporarily)

> so 3 and 4
> aren't all too relevant. As I said before I've asked internally about this and got
> mixed answers so I'm still chasing it down.

Ok.

-Andi