Re: [PATCH] mm/special: Create generic fallbacks for pte_special() and pte_mkspecial()

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Linux MM <linux-mm@kvack.org>,
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Subject: Re: [PATCH] mm/special: Create generic fallbacks for pte_special() and pte_mkspecial()
Date: Mon, 2 Mar 2020 09:19:00 +0100	[thread overview]
Message-ID: <CAMuHMdXnUeYib2dMALyzrW8LKhTjsnGFsqALoTxVHzPGc+OUTg@mail.gmail.com> (raw)
In-Reply-To: <1583114190-7678-1-git-send-email-anshuman.khandual@arm.com>

Hi Anshuman,

Thanks for your patch!

On Mon, Mar 2, 2020 at 2:56 AM Anshuman Khandual
<anshuman.khandual@arm.com> wrote:
> Currently there are many platforms that dont enable HAVE_ARCH_PTE_SPECIAL

ARCH_HAS_PTE_SPECIAL

> but required to define quite similar fallback stubs for special page table
> entry helpers such as pte_special() and pte_mkspecial(), as they get build
> in generic MM without a config check. This creates two generic fallback
> stub definitions for these helpers, eliminating much code duplication.
>
> mips platform has a special case where pte_special() and pte_mkspecial()
> visibility is wider than what HAVE_ARCH_PTE_SPECIAL enablement requires.

ARCH_HAS_PTE_SPECIAL

> This restricts those symbol visibility in order to avoid redefinitions
> which is now exposed through this new generic stubs and subsequent build
> failure. arm platform set_pte_at() definition needs to be moved into a C
> file just to prevent a build failure.

> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>

>  arch/m68k/include/asm/mcf_pgtable.h      | 10 ------
>  arch/m68k/include/asm/motorola_pgtable.h |  2 --
>  arch/m68k/include/asm/sun3_pgtable.h     |  2 --

For m68k:
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds