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

[Oleg Nesterov <oleg@redhat.com>]

On 07/13, James Morris wrote:
>
> 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 ?

Yes, this is on top of rework-fix-is_single_threaded.patch

Given that David acked these changes, I guess they will go
to -mm soon.

> Can it be merged via security-testing#next?

Please do what you think right, I don't know what will be more
convenient to you and Andrew.

Oleg.