On Wed, Aug 28, 2013 at 05:33:49PM +0800, Xiao Guangrong wrote: > > Or what if desc is moved to another rmap, but then it > > is moved back to initial rmap (but another place in the desc list) so > > the check here will not catch that we need to restart walking? > > It is okay. We always add the new desc to the head, then we will walk > all the entires under this case. > Which races another question: What if desc is added in front of the list behind the point where lockless walker currently is? > Right? Not sure. While lockless walker works on a desc rmap can be completely destroyed and recreated again. It can be any order. -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
