On Tue, 2012-08-21 at 16:52 +0300, Michael S. Tsirkin wrote: > > + rcu_read_lock(); > > + mapping = rcu_dereference(page->mapping); > > + if (mapping_balloon(mapping)) > > + ret = true; > > + rcu_read_unlock(); > > This looks suspicious: you drop rcu_read_unlock > so can't page switch from balloon to non balloon?
RCU read lock is a non-exclusive lock, it cannot avoid anything like that. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/