On Sat, May 28, 2011 at 4:24 PM, Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > > That said, I do agree with the "anon_vma_root" part of your patch. I > just think you mixed up two independent issues with it: the fact that > we may be unlocking a new root, and the precise check used to > determine whether the anon_vma might have changed. Thinking some more about it, I end up agreeing with the whole patch. The "page_mapped()" test is what we use in the slow-path after incrementing the anon_vma count too when the trylock didn't work too, so it can't be too wrong. So I'm going to apply it as-is as an improvement (at least we won't be unlocking the wrong anon_vma root), and hope that you and Peter end up agreeing about what the sufficient test is for whether the anon_vma is the right one. 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>