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Date:   Fri, 8 Nov 2019 13:35:15 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Quentin Perret <qperret@google.com>
Cc:     Kirill Tkhai <ktkhai@virtuozzo.com>, linux-kernel@vger.kernel.org,
        aaron.lwe@gmail.com, valentin.schneider@arm.com, mingo@kernel.org,
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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 Fri, Nov 08, 2019 at 12:15:26PM +0000, Quentin Perret wrote:
> Right, with a single loop you'll have to re-iterate the classes from
> the start in case of RETRY_TASK, but you're re-iterating all the classes
> too with this patch. You're doing a little less work in the second loop
> though, so maybe it's worth it. 

The thing with the restart is that it'll make your head explode when we
go do core-scheduling.

> And I was the one worried about
> refactoring the code too much close to the release, so maybe that's for
> another time ;)

It is either this patch or reverting a bunch of patches :/