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Subject: Re: [PATCH RT 1/3] alarmtimer: Prevent live lock in alarm_cancel()
To:     Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc:     linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org,
        Thomas Gleixner <tglx@linutronix.de>,
        Steven Rostedt <rostedt@goodmis.org>, stable-rt@vger.kernel.org
References: <20180328100746.18668-1-bigeasy@linutronix.de>
From:   Daniel Wagner <wagi@monom.org>
Message-ID: <c248f69e-1016-e7ec-64c2-1b8756524a49@monom.org>
Date:   Tue, 3 Apr 2018 20:32:36 +0200
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Hi Sebastian,

On 03/28/2018 12:07 PM, Sebastian Andrzej Siewior wrote:
> If alarm_try_to_cancel() requires a retry, then depending on the
> priority setting the retry loop might prevent timer callback completion
> on RT. Prevent that by waiting for completion on RT, no change for a
> non RT kernel.
> 
> Cc: stable-rt@vger.kernel.org

How relevant is this serie for trees before eae1c4ae275f ("posix-timers: 
Make use of cancel/arm callbacks")? Patch #2 seems to depend on that 
change which was added in v4.12.

Thanks,
Daniel