Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> writes: > On Fri, 2014-11-21 at 13:57 +0000, Mel Gorman wrote: >> Convert existing users of pte_numa and friends to the new helper. Note >> that the kernel is broken after this patch is applied until the other >> page table modifiers are also altered. This patch layout is to make >> review easier. > > Aneesh, the removal of the DSISR_PROTFAULT checks, I wonder if we might > break something here ... (I know, I asked for them to be removed :-) > That is the reason I converted that to a WARN_ON in later patch. > IE, we basically bounce all protection checks to the "normal" VMA > protection checking, so far so good... > > But what about the subpage protection stuff ? Will that still work ? > I did look at that before. So if we had subpage access limitted, when we take a fault for that subpage, we bail out early in hash_page_mm. (with rc = 2). low_hash_fault handle that case directly. We will not end up calling do_page_fault. Now, hash_preload can possibly insert an hpte in hash page table even if the access is not allowed by the pte permissions. But i guess even that is ok. because we will fault again, end-up calling hash_page_mm where we handle that part correctly. -aneesh -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>