Re: [PATCH v2 -mm 2/2] current_is_single_threaded: don't use ->mmap_sem

James Morris
2009-07-12T22:12:53Z

On Fri, 10 Jul 2009, David Howells wrote:

> > However we can avoid ->mmap_sem and rely on rcu/barriers:
> >
> > - if we do not see the exiting parent on thread/process list
> > we see the result of list_del_rcu(), in this case we must
> > also see the result of list_add_rcu() which does wmb().
> >
> > - if we do see the parent but its ->mm == NULL, we need rmb()
> > to make sure we can't miss the child.
> >
> > Signed-off-by: Oleg Nesterov <oleg@redhat.com>
>
> Acked-by: David Howells <dhowells@redhat.com>

I gather this stuff is going into -mm ?

Can it be merged via security-testing#next?

--
James Morris
<jmorris@namei.org>