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Date:   Tue, 28 Jun 2022 17:21:22 +0100
From:   Aaron Tomlin <atomlin@redhat.com>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     mcgrof@kernel.org, christophe.leroy@csgroup.eu, cl@linux.com,
        mbenes@suse.cz, akpm@linux-foundation.org, jeyu@kernel.org,
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        daniel.thompson@linaro.org, hch@infradead.org,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-rt-users <linux-rt-users@vger.kernel.org>
Subject: Re: [PATCH v11 10/14] module: kallsyms: Fix suspicious rcu usage
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References: <20220310102413.3438665-1-atomlin@redhat.com>
 <20220310102413.3438665-11-atomlin@redhat.com>
 <20220627235612.4796c837@gandalf.local.home>
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On Mon 2022-06-27 23:56 -0400, Steven Rostedt wrote:
> > +	preempt_enable();
> 
>         ^^^^^^^^^^^^^^^^^
> 
> This just introduced an unbounded latency and will fail PREEMPT_RT.
> 

Hi Steve,

Sorry about that!

If I understand correctly, there is absolutely no need to explicitly
disable preemption in this context. I will use: rcu_read_lock() and
rcu_read_unlock(), respectively, which will then be suitable for the
preemptible RCU implementation.


Kind regards,

-- 
Aaron Tomlin