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Date:   Tue, 18 Feb 2020 15:54:06 -0800
From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Peter Zijlstra <peterz@infradead.org>, rcu@vger.kernel.org,
        linux-kernel@vger.kernel.org, kernel-team@fb.com, mingo@kernel.org,
        jiangshanlai@gmail.com, dipankar@in.ibm.com,
        akpm@linux-foundation.org, mathieu.desnoyers@efficios.com,
        josh@joshtriplett.org, tglx@linutronix.de, dhowells@redhat.com,
        edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com,
        joel@joelfernandes.org
Subject: Re: [PATCH tip/core/rcu 1/3] rcu-tasks: *_ONCE() for
 rcu_tasks_cbs_head
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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@kernel.org> 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