On Tue, Mar 31, 2009 at 03:00:02AM +0300, Izik Eidus wrote: > When using mmu notifiers, we are allowed to remove the page count > reference tooken by get_user_pages to a specific page that is mapped > inside the shadow page tables. > > This is needed so we can balance the pagecount against mapcount > checking. > > (Right now kvm increase the pagecount and does not increase the > mapcount when mapping page into shadow page table entry, > so when comparing pagecount against mapcount, you have no > reliable result.)
IMO ifdef'ing CONFIG_MMU_NOTIFIERS here (and keeping the ref if unset) instead of in the backward compat code gives less room for headaches. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
