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Date:   Fri, 8 Nov 2019 11:58:10 +0000
From:   Quentin Perret <qperret@google.com>
To:     Valentin Schneider <valentin.schneider@arm.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Kirill Tkhai <ktkhai@virtuozzo.com>,
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        rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de,
        kernel-team@android.com, john.stultz@linaro.org
Subject: Re: NULL pointer dereference in pick_next_task_fair
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On Friday 08 Nov 2019 at 11:47:44 (+0000), Valentin Schneider wrote:
> I think we can ignore RETRY_TASK because this happens before the picking loop,
> so we'll observe any new DL/RT task that got enqueued while newidle released
> the lock. This also means we can safely break the balance loop in
> pick_next_task() when we get RETRY_TASK, because we've got something to pick
> (some new RT/DL task).

Ah right, the second loop always iterates from DL, so that works.

> This wants a comment though, methinks.

+1 :)

Thanks,
Quentin