On Mon, Nov 14, 2016 at 11:48:22AM -0500, Johannes Weiner wrote: > On Mon, Nov 14, 2016 at 10:52:50AM -0500, Johannes Weiner wrote: > > On Mon, Nov 14, 2016 at 05:29:02PM +0300, Kirill A. Shutemov wrote: > > > @@ -1400,7 +1400,9 @@ static void collapse_shmem(struct mm_struct *mm, > > > PAGE_SIZE, 0); > > > > > > spin_lock_irq(&mapping->tree_lock); > > > - > > > + slot = radix_tree_lookup_slot(&mapping->page_tree, index); > > > + VM_BUG_ON_PAGE(page != radix_tree_deref_slot_protected(slot, > > > + &mapping->tree_lock), page); > > > VM_BUG_ON_PAGE(page_mapped(page), page); > > > > That looks good to me. The slot may get relocated, but the content > > shouldn't change with the page locked. > > > > Are you going to send a full patch with changelog and sign-off? If so, > > please add: > > > > Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx> > > Just to clarify, this is in addition to my radix_tree_iter_next() > change. The iterator still needs to be reloaded because the number of > valid slots that come after the current one can change as well. Could you just amend all these fixups into your patch? -- Kirill A. Shutemov -- 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>