On Mon, Feb 04, 2008 at 11:09:01AM -0800, Christoph Lameter wrote: > On Sun, 3 Feb 2008, Andrea Arcangeli wrote: > > > > Right but that pin requires taking a refcount which we cannot do. > > > > GRU can use my patch without the pin. XPMEM obviously can't use my > > patch as my invalidate_page[s] are under the PT lock (a feature to fit > > GRU/KVM in the simplest way), this is why an incremental patch adding > > invalidate_range_start/end would be required to support XPMEM too. > > Doesnt the kernel in some situations release the page before releasing the > pte lock? Then there will be an external pte pointing to a page that may > now have a different use. Its really bad if that pte does allow writes.
Sure the kernel does that most of the time, which is for example why I had to use invalidate_page instead of invalidate_pages inside zap_pte_range. Zero problems with that (this is also the exact reason why I mentioned the tlb flushing code would need changes to convert some page in pages). ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
