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Date:   Wed, 18 May 2022 00:22:24 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Kees Cook <keescook@chromium.org>
Cc:     Christophe de Dinechin <dinechin@redhat.com>,
        Ingo Molnar <mingo@redhat.com>,
        Juri Lelli <juri.lelli@redhat.com>,
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        Daniel Bristot de Oliveira <bristot@redhat.com>,
        linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH v3] sched/core: Address classes via __begin_sched_classes
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On Tue, May 17, 2022 at 10:35:44AM -0700, Kees Cook wrote:

> What you've got below is almost exactly what I had in my first attempt
> at this (that I never posted). What I was missing and couldn't track
> down were the places you used sched_class_above(). I should have sent
> _that_ patch and asked where the comparisons were that I couldn't find.
> I think what you've got is much cleaner, as it makes the for loop use
> the normal iterator idiom.

Don't feel too bad; I forgot about the comparison in
check_preempt_curr() myself and cursed a while trying to figure out why
it stopped booting.

Anyway; I suppose I'll go queue the thing in sched/core so we can forget
about all this again.