Re: [PATCH] mm: remove kern_addr_valid() completely

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
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Subject: Re: [PATCH] mm: remove kern_addr_valid() completely
Date: Tue, 18 Oct 2022 09:30:42 +0200	[thread overview]
Message-ID: <CAMuHMdWwAgPkifAkah7MoBKBoyB4tb+HM5cgvenwNFaAfbg+UQ@mail.gmail.com> (raw)
In-Reply-To: <20221018074014.185687-1-wangkefeng.wang@huawei.com>

On Tue, Oct 18, 2022 at 9:25 AM Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
> Most architectures(except arm64/x86/sparc) simply return 1 for
> kern_addr_valid(), which is only used in read_kcore(), and it
> calls copy_from_kernel_nofault() which could check whether the
> address is a valid kernel address, so no need kern_addr_valid(),
> let's remove unneeded kern_addr_valid() completely.
>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>

>  arch/m68k/include/asm/pgtable_mm.h        |  2 -
>  arch/m68k/include/asm/pgtable_no.h        |  1 -

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

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