Re: [Y2038] [PATCH 3/8] powerpc: fix vdso32 for ppc64le

From: Ben Hutchings
Date: Thu Nov 21 2019 - 10:56:32 EST


On Thu, 2019-11-21 at 11:02 +0100, Arnd Bergmann wrote:
> On Wed, Nov 20, 2019 at 10:49 PM Ben Hutchings
> <ben.hutchings@xxxxxxxxxxxxxxx> wrote:
> > 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@xxxxxxxxxxxxxxx> 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).
>
> Ok, I had missed that detail. Should I just drop my patch then?

I think so.

Ben.

--
Ben Hutchings, Software Developer Codethink Ltd
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