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Date:   Fri, 24 Sep 2021 15:31:44 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Kees Cook <keescook@chromium.org>
Cc:     Qi Zheng <zhengqi.arch@bytedance.com>,
        Thomas Gleixner <tglx@linutronix.de>,
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Subject: Re: [PATCH] proc: Disable /proc/$pid/wchan
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References: <20210923233105.4045080-1-keescook@chromium.org>
 <202109231636.C233D6D82@keescook>
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On Thu, Sep 23, 2021 at 04:38:26PM -0700, Kees Cook wrote:
> On Thu, Sep 23, 2021 at 04:31:05PM -0700, Kees Cook wrote:

> If the fair scheduler would actually benefit from still using get_wchan,
> I think this patch:
> https://lore.kernel.org/all/20210831083625.59554-1-zhengqi.arch@bytedance.com/
> should still be applied too.
> 
> If not, we can rip get_wchan() out completely (across all
> architectures).

The scheduler doesn't care, it's kernel/profile.c and please kill that
right along with wchan, good riddance.