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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 18 Aug 2016 11:09:48 +1000
From:	Nicholas Piggin <npiggin@...il.com>
To:	Michal Marek <mmarek@...e.cz>
Cc:	Stephen Rothwell <sfr@...b.auug.org.au>,
	linux-kernel@...r.kernel.org, linux-next@...r.kernel.org,
	Al Viro <viro@...iv.linux.org.uk>,
	PowerPC <linuxppc-dev@...ts.ozlabs.org>
Subject: Re: linux-next: build warnings after merge of the kbuild tree

On Wed, 17 Aug 2016 14:59:59 +0200
Michal Marek <mmarek@...e.cz> wrote:

> On 2016-08-17 03:44, Stephen Rothwell wrote:
> > Hi Michal,
> > 
> > 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.

Thanks,
Nick