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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Fri, 18 Jan 2019 20:33:25 +0100
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Subject: Re: [PATCH v2 29/29] y2038: add 64-bit time_t syscalls to all 32-bit architectures
To:     Andy Lutomirski <luto@kernel.org>
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On Fri, Jan 18, 2019 at 7:50 PM Andy Lutomirski <luto@kernel.org> wrote:
> On Fri, Jan 18, 2019 at 8:25 AM Arnd Bergmann <arnd@arndb.de> wrote:
> > - Once we get to 512, we clash with the x32 numbers (unless
> >   we remove x32 support first), and probably have to skip
> >   a few more. I also considered using the 512..547 space
> >   for 32-bit-only calls (which never clash with x32), but
> >   that also seems to add a bit of complexity.
>
> I have a patch that I'll send soon to make x32 use its own table.  As
> far as I'm concerned, 547 is *it*.  548 is just a normal number and is
> not special.  But let's please not reuse 512..547 for other purposes
> on x86 variants -- that way lies even more confusion, IMO.

Fair enough, the space for those numbers is cheap enough here.
I take it you mean we also should not reuse that number space if
we were to decide to remove x32 soon, but you are not worried
about clashing with arch/alpha when everything else uses consistent
numbers?

       Arnd