Re: linux-next: build failure after merge of the rcu tree

[Paul E. McKenney]

On Thu, Dec 12, 2019 at 03:26:13PM +1100, Stephen Rothwell wrote:
> Hi Paul,
> 
> On Wed, 11 Dec 2019 20:07:37 -0800 "Paul E. McKenney" <paulmck@xxxxxxxxxx> wrote:
> >
> > On Thu, Dec 12, 2019 at 01:45:16PM +1100, Stephen Rothwell wrote:
> > > Hi all,
> > > 
> > > After merging the rcu tree, today's linux-next build (x86_64 allmodconfig)
> > > failed like this:
> > > 
> > > drivers/misc/watch_queue.c: In function 'watch_queue_set_filter':
> > > drivers/misc/watch_queue.c:526:2: error: implicit declaration of function 'rcu_swap_protected' [-Werror=implicit-function-declaration]
> > >   526 |  rcu_swap_protected(wqueue->filter, wfilter,
> > >       |  ^~~~~~~~~~~~~~~~~~
> > > 
> > > Caused by commit
> > > 
> > >   af8c9224182e ("rcu: Remove rcu_swap_protected()")
> > > 
> > > interacting with commit
> > > 
> > >   fe78d401ca6b ("General notification queue with user mmap()'able ring buffer")
> > > 
> > > from the keys tree.
> > > 
> > > I have added the following merge fix patch for today:
> > > 
> > > From: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
> > > Date: Thu, 12 Dec 2019 13:37:52 +1100
> > > Subject: [PATCH] rcu: fix up for "Remove rcu_swap_protected()"
> > > 
> > > Signed-off-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>  
> > 
> > Reviewed-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
> 
> Thanks.
> 
> > I would be happy to take this if desired, but it would probably be better
> > for this to be applied directly to the keys tree.  Either way, please let
> > me know.
> 
> Well, you can't take this fix up without merging the keys tree ... and
> the keys tree is currently in flux so it should be easy for it to be
> applied there since rcu_replace_pointer() already exists in Linus'
> tree, right?.

Yes, so sounds like a plan to me.  ;-)

							Thanx, Paul