Re: [PATCH v2] ld.so.8: Update "Hardware capabilities" section for glibc 2.31.

["Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>]

Hi Carlos,

What's the status of this patch?

Thanks,

Michael


On Tue, 2 Jun 2020 at 08:14, Florian Weimer <fweimer@redhat.com> wrote:
>
> * Carlos O'Donell:
>
> > +Care should be taken when packaging such application with a package manager,
> > +particularly the scenario where an optimized library is being removed.  With
> > +certain package managers, particularly rpm, the newer version of the
>
> Twice “particularly”.
>
> > +application is installed first, which means that for a period of time during
> > +the upgrade all applications that use the library may start with a mixed set of
> > +libraries e.g.  the old library from the feature-based search path, and new
>
> Commas arount e.g.?
>
> > +libraries from the upgrade. To avoid this scenario the new library version
> > +should delete all known optimized libraries in the post-install phase.
>
> There is a different mechanism: Debian has patched glibc to disable
> hwcap subdirectors if the file /etc/ld.so.nohwcap exists.
>
> You now list the AT_PLATFORM directories (determined by the kernel on
> most architectures) along the regular hwcaps directories, although they
> are handled somewhat differently.  For example, on s390x, if you have a
> “z15” machine (as indicated by AT_PLATFORM), the “z13” subdirectory is
> not selected.  ldconfig will add it to the cache, but it will not be
> used at run time.  I'm not sure if your proposed description gives
> readers the right idea what happens.
>
> Thanks,
> Florian
>


--
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
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