On Thu, Jun 21, 2012 at 03:36:01PM +1000, Michael Ellerman wrote: > On Wed, 2012-06-20 at 17:50 +1000, Stephen Rothwell wrote: > > Hi all, > > > > After merging the final tree, today's linux-next build (powerpc > > allyesconfig) failed like this: > > > > powerpc64-linux-ld: arch/powerpc/net/built-in.o: In function `bpf_slow_path_word': > > (.text+0x90): sibling call optimization to `skb_copy_bits' does not allow automatic multiple TOCs; recompile with -mminimal-toc or -fno-optimize-sibling-calls, or make `skb_copy_bits' extern > > > Those seem to be caused because we don't have a nop after the call, > meaning we can't patch the TOC pointer on the way back. Adding a nop > fixes those. > > But, then I get 32,410 variants of this: > > powerpc64-linux-ld: /src/next/net/openvswitch/vport-netdev.c:189:(.text+0x89b990): > sibling call optimization to `_restgpr0_28' does not allow automatic multiple TOCs; > recompile with -mminimal-toc or -fno-optimize-sibling-calls, or make `_restgpr0_28' extern > > These functions should not need a TOC in the first place. There is code in the linker (for 64 bit only: bfd/elf64-ppc.c) to automatically generate them whenever they are needed. I suspect you compile with -Os. But I don't think you can use these functions when doing a sibling call since restgpr0_nn implies a return to the caller. restgpr1_nn would be different... > And those are generated calls so I don't see how we can fix them. > > > I started building with gcc 4.6.3/binutils 2.22 today. gcc > > 4.6.0/binutils 2.21 do not produce this error, it produces this instead > > (which has been happening for a long time): > > > > powerpc64-linux-ld: TOC section size exceeds 64k > > > So presumably there's some new error checking that we're hitting, I > imagine it was always broken, but now it's being more explicit. I'm not so sure. I suspect gcc, but upgrading gcc and binutils at the same time may not be the wisest... Gabriel -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
