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From:   Marco Elver <elver@google.com>
Date:   Thu, 4 Mar 2021 15:43:50 +0100
Message-ID: <CANpmjNPk0GYuiz1YZddJ1GjZuUXUrXFVZujoaH0UKDknpc-vgQ@mail.gmail.com>
Subject: Re: [PATCH mm] kfence: fix reports if constant function prefixes exist
To:     Marco Elver <elver@google.com>,
        Andrew Morton <akpm@linux-foundation.org>
Cc:     Alexander Potapenko <glider@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Andrey Konovalov <andreyknvl@google.com>,
        Jann Horn <jannh@google.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux Memory Management List <linux-mm@kvack.org>,
        kasan-dev <kasan-dev@googlegroups.com>,
        Christophe Leroy <christophe.leroy@csgroup.eu>
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On Thu, 4 Mar 2021 at 15:40, Marco Elver <elver@google.com> wrote:
> Some architectures prefix all functions with a constant string ('.' on
> ppc64). Add ARCH_FUNC_PREFIX, which may optionally be defined in
> <asm/kfence.h>, so that get_stack_skipnr() can work properly.
>
> Link: https://lkml.kernel.org/r/f036c53d-7e81-763c-47f4-6024c6c5f058@csgroup.eu
> Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
> Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
> Signed-off-by: Marco Elver <elver@google.com>
> ---

For further context, the corresponding ppc64-enablement patch is was
just sent by Christophe:

  https://lkml.kernel.org/r/afaec81a551ef15345cb7d7563b3fac3d7041c3a.1614868445.git.christophe.leroy@csgroup.eu

But there is no strict dependency between the patches, only that the
stack traces that KFENCE prints aren't as pretty without the
ARCH_FUNC_PREFIX patch.

So it should be fine to take them through different trees, as long as
they both make the next merge window.

Thanks,
-- Marco