lkml.org 
[lkml]   [2012]   [Jun]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: linux-next: build failure after merge of the final tree (powerpc related)
    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


    \
     
     \ /
      Last update: 2012-06-21 10:41    [W:4.554 / U:0.188 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site