Re: [PATCH tip/core/rcu 1/3] rcu-tasks: *_ONCE() for rcu_tasks_cbs_head

From: Paul E. McKenney
Date: Tue Feb 18 2020 - 18:54:09 EST

On Tue, Feb 18, 2020 at 06:13:23PM -0500, Steven Rostedt wrote:
> On Tue, 18 Feb 2020 14:54:55 -0800
> "Paul E. McKenney" <paulmck@xxxxxxxxxx> wrote:
> > This data race was reported by KCSAN. Not appropriate for backporting
> > due to failure being unlikely and due to the mild consequences of the
> > failure, namely a confusing rcutorture console message.
> >
> I've seen patches backported for less. :-/
> Really, any statement that says something may go awry with the code,
> will be an argument to backport it.

You aren't kidding! Rumor has it that someone tried backporting the
RCU flavor-consolidation work, for but one example. Though I cannot
help but salute the level of insanity represented by that attempt. ;-)

Thanx, Paul