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From:   Ard Biesheuvel <ardb@kernel.org>
Date:   Fri, 3 Jun 2022 10:17:35 +0200
Message-ID: <CAMj1kXGAf2twVczdxOCnYVPefnekT9U4J08+-5=GygAd7htDXg@mail.gmail.com>
Subject: Re: [PATCH] ARM: initialize jump labels before setup_machine_fdt()
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Russell King <linux@armlinux.org.uk>,
        Russell King <rmk+kernel@armlinux.org.uk>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Stephen Boyd <swboyd@chromium.org>,
        "# 3.4.x" <stable@vger.kernel.org>
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On Fri, 3 Jun 2022 at 10:12, Jason A. Donenfeld <Jason@zx2c4.com> wrote:
>
> Hi Ard,
>
> On 6/3/22, Ard Biesheuvel <ardb@kernel.org> wrote:
> > The problem is that your original patch
>
> You remain extremely unpleasant to communicate with.

Noted.

> Can we keep
> things on topic please?
>

Sure. Are you saying the original patch is off-topic? Isn't that the
patch that caused the regression to begin with?

> > As far as I can tell, the early patching code on ARM does not rely on
> > the early fixmap code. Did you try just moving jump_label_init()
> > earlier in the function?
> >
> > Also, how did you test this change?
>
> Just booting a few configs in QEMU. I don't have access to real
> hardware right now unfortunately.
>
> Let me give a try to just moving the jump_label_init() function alone.
> That'd certainly make this patch a lot more basic, which would be a
> good thing, and might assuage your well justified concerns that too
> much boot order churn will break something subtle. I was just afraid
> of complicated intermingling with the other stuff after I saw that
> arm64 did things in the other order. But maybe that's silly.
>
> I'll send a v2 if that works, and send an update here if it doesn't.
> Thanks for the suggestion.
>
> Jason