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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Wed, 20 Nov 2019 20:35:07 +0100
Message-ID: <CAK8P3a3BPhX_NRFj66WyRLQUOCV-FGRjmPCgB7gqxMoK8hfywg@mail.gmail.com>
Subject: Re: [Y2038] [PATCH 3/8] powerpc: fix vdso32 for ppc64le
To:     Ben Hutchings <ben.hutchings@codethink.co.uk>
Cc:     y2038 Mailman List <y2038@lists.linaro.org>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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On Wed, Nov 20, 2019 at 8:13 PM Ben Hutchings
<ben.hutchings@codethink.co.uk> wrote:
>
> On Fri, 2019-11-08 at 21:34 +0100, Arnd Bergmann wrote:
> > On little-endian 32-bit application running on 64-bit kernels,
> > the current vdso would read the wrong half of the xtime seconds
> > field. Change it to return the lower half like it does on
> > big-endian.
>
> ppc64le doesn't have 32-bit compat so this is only theoretical.

That is probably true. I only looked at the kernel, which today still
supports compat mode for ppc64le, but I saw the patches to disable
it, and I don't think anyone has even attempted building user space
for it.

       Arnd