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Date: Fri, 31 Jul 2015 19:16:27 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-kernel@vger.kernel.org, Rusty Russell <rusty@rustcorp.com.au>,
        Ananth N Mavinakayanahalli <ananth@in.ibm.com>,
        Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>,
        tglx@linutronix.de
Subject: Re: [RFC 2/4] jump_label: use rcu_read_lock() while accessing
 __module_*()
Message-ID: <20150731171627.GA25159@twins.programming.kicks-ass.net>
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On Fri, Jul 31, 2015 at 07:08:06PM +0200, Sebastian Andrzej Siewior wrote:
> __jump_label_mod_text_reserved() should most likely use rcu_read_lock()
> while invoking __module_text_address(). I'm not sure there is anything
> to protect the module pointed by `start' and `end' from removal.
> I *think* the protection is based on the preempt_disable() in
> check_kprobe_address_safe(). That preempt_disable however does not
> protect from module removal on a SMP machine.

Yes it does, seeing how it uses sync_sched().