On Fri, 7 May 2010, Mel Gorman wrote: > > Page migration requires rmap to be able to find all migration ptes > created by migration. If the second rmap_walk clearing migration PTEs > misses an entry, it is left dangling causing a BUG_ON to trigger during > fault. For example; So I still absolutely detest this patch. Why didn't the other - much simpler - patch work? The one Rik pointed to: http://lkml.org/lkml/2010/4/30/198 and didn't do that _disgusting_ temporary anon_vma? Alternatively, why don't we just take the anon_vma lock over this region, so that rmap can't _walk_ the damn thing? Linus -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>