On Mon, Feb 11, 2008 at 04:27:23PM +0100, Andi Kleen wrote: > > > > 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.
BTW, making pages not present is required only while changing the attribute from WB to WC or WC to WB. I think this step is for avoiding attribute aliasing for speculative accesses. For UC, we don't have speculative accesses and such we probably don't need it. So WC support through PAT should take care of it. > (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) True. Perhaps for WC chages we can assume the ownership? thanks, suresh -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
