On Wed, Aug 27, 2014 at 01:50:28PM +0100, Steve Capper wrote: > On Wed, Aug 27, 2014 at 09:54:42AM +0100, Will Deacon wrote: > > On Thu, Aug 21, 2014 at 04:43:27PM +0100, Steve Capper wrote: > > > @@ -672,3 +676,277 @@ struct page *get_dump_page(unsigned long addr) > > > return page; > > > } > > > #endif /* CONFIG_ELF_CORE */ > > > + > > > +#ifdef CONFIG_HAVE_RCU_GUP > > > + > > > +#ifdef __HAVE_ARCH_PTE_SPECIAL > > > > Do we actually require this (pte special) if hugepages are disabled or > > not supported? > > We need this logic if we want use fast_gup on normal pages safely. The special > bit indicates that we should not attempt to take a reference to the underlying > page. > > Huge pages are guaranteed not to be special. Gah, I somehow mixed up sp-litting and sp-ecial. Step away from the computer. In which case, the patch looks fine. You might need to repost with '[PATCH]' instead of '[PATH]', in case you confused people's filters. Will -- 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>