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Date: Wed, 24 May 2017 12:57:37 +0200
From: Heiko Carstens <heiko.carstens@de.ibm.com>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Sebastian Siewior <bigeasy@linutronix.de>,
        Paul McKenney <paulmck@linux.vnet.ibm.com>,
        Martin Schwidefsky <schwidefsky@de.ibm.com>,
        linux-s390@vger.kernel.org
Subject: Re: [patch V3 28/32] s390: Prevent hotplug rwsem recursion
References: <20170524081511.203800767@linutronix.de>
 <20170524081549.354513406@linutronix.de>
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On Wed, May 24, 2017 at 10:15:39AM +0200, Thomas Gleixner wrote:
> The text patching functions which are invoked from jump_label and kprobes
> code are protected against cpu hotplug at the call sites.
> 
> Use stop_machine_cpuslocked() to avoid recursion on the cpu hotplug
> rwsem. stop_machine_cpuslocked() contains a lockdep assertion to catch any
> unprotected callers.
> 
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
> Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
> Cc: linux-s390@vger.kernel.org
> ---
>  arch/s390/kernel/jump_label.c |    2 +-
>  arch/s390/kernel/kprobes.c    |    4 ++--
>  2 files changed, 3 insertions(+), 3 deletions(-)

Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>