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Date:   Wed, 6 Jan 2021 20:16:45 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Willem de Bruijn <willemb@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        David Miller <davem@davemloft.net>,
        Jonathan Lemon <jonathan.lemon@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
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        "the arch/x86 maintainers" <x86@kernel.org>,
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        Ingo Molnar <mingo@kernel.org>,
        Juri Lelli <juri.lelli@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
        Daniel Bristot de Oliveira <bristot@redhat.com>,
        Netdev <netdev@vger.kernel.org>
Subject: Re: [BUG] from x86: Support kmap_local() forced debugging
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On Wed, 6 Jan 2021 17:03:48 -0800
Linus Torvalds <torvalds@linux-foundation.org> wrote:

> (although I wonder how/why the heck you've enabled
> CC_OPTIMIZE_FOR_SIZE=y, which is what causes "memcpy()" to be done as
> that "rep movsb". I thought we disabled it because it's so bad on most
> cpus).

Why?

Because to test x86_32, I have a Fedora Core 13 (yes 13!) partition
(baremetal) that I use. And the .config I use for it hasn't changed
since that time ;-) (except to add new features that I want to test on
x86_32).

Anyway, I'll test out your patch. Thanks for investigating this.

-- Steve