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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Wed, 3 Jun 2020 09:35:12 +0200
Message-ID: <CAMuHMdV-Par79SYe75HzJsEd2cwEDhGPK+Nj0zUD8eAy9aDj1A@mail.gmail.com>
Subject: Re: [PATCH v2] sh: Implement __get_user_u64() required for 64-bit get_user()
To:     John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc:     Linux-sh list <linux-sh@vger.kernel.org>,
        Rich Felker <dalias@libc.org>,
        Yoshinori Sato <ysato@users.sourceforge.jp>,
        Michael Karcher <kernel@mkarcher.dialup.fu-berlin.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Hi Adrian,

On Wed, Jun 3, 2020 at 9:20 AM John Paul Adrian Glaubitz
<glaubitz@physik.fu-berlin.de> wrote:
> On 5/31/20 12:47 PM, John Paul Adrian Glaubitz wrote:
> >  Changes since v1:
> >  - Replace single mov instruction for exception handling
> >    in case of invalid load
>
> Yutaka Niibe has had a look at my patch and he says, we might have to add
> an entry for the fault handling of the upper word.
>
> Quote:
>
> > (1) I think that there is possibility that the second access to user
> > space fails (while the first access succeeds).  IIUC, it's good have
> > an entry in __ex_tables for the second access too, like:
> >     ".long 1b+2, 3b\n\t"
> > I don't know if the expression "1b+2" is correct, my intention is
> > detecting the failure in the seccond access.

So just add another numeric label, like is done on 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