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Message-ID: <d82ef7b94b9c3adc4fbb4e62c17b81a868fb32d8.camel@codethink.co.uk>
Subject: Re: [Y2038] [PATCH 3/8] powerpc: fix vdso32 for ppc64le
From:   Ben Hutchings <ben.hutchings@codethink.co.uk>
To:     Arnd Bergmann <arnd@arndb.de>
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>
Date:   Wed, 20 Nov 2019 21:49:47 +0000
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         <fdcb510863c801f1f64448e558ee0f8ed20db418.camel@codethink.co.uk>
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On Wed, 2019-11-20 at 20:35 +0100, Arnd Bergmann wrote:
> 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.

COMPAT is still enabled for some reason, but VDSO32 isn't (since 4.2).

Ben.

-- 
Ben Hutchings, Software Developer                         Codethink Ltd
https://www.codethink.co.uk/                 Dale House, 35 Dale Street
                                     Manchester, M1 2HF, United Kingdom