Re: linux-next: build warnings after merge of the kbuild tree

From: Stephen Rothwell
Date: Thu Aug 18 2016 - 23:49:14 EST


Hi Nick,

On Thu, 18 Aug 2016 11:09:48 +1000 Nicholas Piggin <npiggin@xxxxxxxxx> wrote:
>
> On Wed, 17 Aug 2016 14:59:59 +0200
> Michal Marek <mmarek@xxxxxxx> wrote:
>
> > On 2016-08-17 03:44, Stephen Rothwell wrote:
> > >
> > > After merging the kbuild tree, today's linux-next build (powerpc
> > > ppc64_defconfig) produced these warnings:
> > >
> > > WARNING: 25 bad relocations
> > > c000000000cf2570 R_PPC64_ADDR64 __crc___arch_hweight16
> > [...]
> > > Introduced by commit
> > >
> > > 9445aa1a3062 ("ppc: move exports to definitions")
> > >
> > > I have reverted that commit for today.
> > >
> > > [cc-ing the ppc guys for clues - also involved is commit
> > >
> > > 22823ab419d8 ("EXPORT_SYMBOL() for asm")
> > > ]
> >
> > FWIW, I see these warnings as well. Any help from ppc developers is
> > appreciated - should the R_PPC64_ADDR64 be whitelisted for exported asm
> > symbols (their CRCs actually)?
>
> The dangling relocation is a side effect of linker unable to resolve the
> reference to the undefined weak symbols. So the real question is, why has
> genksyms not overridden these symbols with their CRC values?
>
> This may not even be powerpc specific, but I'll poke at it a bit more
> when I get a chance.

Not sure if this is relevant, but with the commit reverted, the
__crc___... symbols are absolute.

00000000f55b3b3d A __crc___arch_hweight16

--
Cheers,
Stephen Rothwell