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From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Tue, 2 Jul 2019 23:56:38 +0200
Message-ID: <CACRpkdb3P6oQTK9FGUkMj4kax8us3rKH6c36pX=HD1_wMqcoJQ@mail.gmail.com>
Subject: Re: [PATCH v6 2/6] ARM: Disable instrumentation for some code
To:     Florian Fainelli <f.fainelli@gmail.com>
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On Tue, Jun 18, 2019 at 12:11 AM Florian Fainelli <f.fainelli@gmail.com> wrote:

> @@ -236,7 +236,8 @@ static int unwind_pop_register(struct unwind_ctrl_block *ctrl,
>                 if (*vsp >= (unsigned long *)ctrl->sp_high)
>                         return -URC_FAILURE;
>
> -       ctrl->vrs[reg] = *(*vsp)++;
> +       ctrl->vrs[reg] = READ_ONCE_NOCHECK(*(*vsp));
> +       (*vsp)++;

I would probably even put in a comment here so it is clear why we
do this. Passers-by may not know that READ_ONCE_NOCHECK() is
even related to KASan.

Other than that,
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij