Re: [PATCH v8 1/5] mm: introduce a common interface for balloonpages mobility

From: Rafael Aquini
Date: Tue Aug 21 2012 - 15:24:26 EST


On Tue, Aug 21, 2012 at 10:13:30PM +0300, Michael S. Tsirkin wrote:
> >
> > I believe rcu_dereference_protected() is what I want/need here, since this code
> > is always called for pages which we hold locked (PG_locked bit).
>
> It would only help if we locked the page while updating the mapping,
> as far as I can see we don't.
>

But we can do it. In fact, by doing it (locking the page) we can easily avoid
the nasty race balloon_isolate_page / leak_balloon, in a much simpler way, IMHO.


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/