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Date:   Thu, 23 Jul 2020 16:51:20 +0100
From:   Qais Yousef <qais.yousef@arm.com>
To:     Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>
Cc:     Doug Anderson <dianders@chromium.org>,
        Juri Lelli <juri.lelli@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
        Patrick Bellasi <patrick.bellasi@matbug.net>,
        Chris Redpath <chris.redpath@arm.com>,
        Lukasz Luba <lukasz.luba@arm.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v7 3/3] sched/uclamp: Fix a deadlock when enabling uclamp
 static key
Message-ID: <20200723155119.gs34voui4jx7cilb@e107158-lin.cambridge.arm.com>
References: <20200716110347.19553-1-qais.yousef@arm.com>
 <20200716110347.19553-4-qais.yousef@arm.com>
 <20200716111328.zkhncw2aurrs4mad@e107158-lin.cambridge.arm.com>
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On 07/16/20 12:13, Qais Yousef wrote:
> On 07/16/20 12:03, Qais Yousef wrote:
> 
> [...]
> 
> > Fix by ensuring we enable the key outside of the critical section in
> > __sched_setscheduler()
> > 
> > Fixes: 46609ce22703 ("sched/uclamp: Protect uclamp fast path code with static key")
> > Signed-off-by: Qais Yousef <qais.yousef@arm.com>
> 
> I am assuming this Fixes tag is still valid given the patch is only in
> tip/sched/core only. And that the hash value won't change after Linus merges
> it.

Gentle ping that this patch is actually a fix that I happened to uncover while
testing this series.

Happy to send separately. It should apply on its own too as it has no
dependency on previous patches.

Thanks

--
Qais Yousef