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Date:   Fri, 5 May 2023 10:06:21 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Joel Fernandes <joel@joelfernandes.org>
Cc:     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Frederic Weisbecker <frederic@kernel.org>,
        Neeraj Upadhyay <quic_neeraju@quicinc.com>,
        Josh Triplett <josh@joshtriplett.org>,
        Boqun Feng <boqun.feng@gmail.com>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        Zqiang <qiang1.zhang@intel.com>, rcu@vger.kernel.org
Subject: Re: [RFC PATCH 3/4] rculist.h: Fix parentheses around macro pointer
 parameter use
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On Thu, 4 May 2023 12:19:38 -0400
Joel Fernandes <joel@joelfernandes.org> wrote:

> >   void f(void)
> >   {
> >           struct test *t1;
> >           struct test **t2 = &t1;
> >
> >           list_for_each_entry_rcu((*t2), &testlist, node) {       /* works */
> >                   //...
> >           }
> >           list_for_each_entry_rcu(*t2, &testlist, node) { /* broken */
> >                   //...
> >           }  
> 
> Yeah it is not clear why anyone would ever want to use it like this.
> Why don't they just pass t1 to list_for_each_entry_rcu() ? I would
> rather it break them and they re-think their code ;).

Remember interfaces should not be enforcing policy unless it's key to the
way the interface works.

-- Steve