The volatile volatile ranges patch set

Just as a minor clarification (and I can understand how this was confusing)...

Minchan's objection mentioned here was somewhat tangential and short-lived. Its stems from a use-case that the Google address-sanitizer folks wanted, where volatility would be sticky and data could be purged, then rewritten and then purged again without any explicit re-marking of volatility.

I *really* don't see how this use case is at all feasible. Especially as a generic implementation. My specific objections where listed here: http://thread.gmane.org/gmane.linux.kernel.mm/116952

And after that Minchan agreed and withdrew his objection:
http://thread.gmane.org/gmane.linux.kernel.mm/116952

Johannes' suggestion for zero-fill behavior is viable, and works more in-line with the existing VMM code by overloading the page clean/dirty state as a marker of volatility. My main objection is that this works well from the VMM perspective, but creates more surprising semantics for userspace.

Those semantics could become less surprising (but still not my ideal) to userspace with his additional suggestion of adding a SIGBUS option to MADV_FREE, so this is a potential route and I *really do* appreciate the feedback and suggestion (Johannes, Hugh and many other folks have been very kind and motivational in discussions at conferences). Its just that I've run a bit out of steam on this one and have other work I need to do.

I still think its a really great and needed feature, and it shames me to feel like I've failed in pushing it upstream. But its my hope someone else might be able to pick up the torch here.