On Tue, 2016-12-01 at 12:14:23 UTC, Michael Ellerman wrote: > From: Ulrich Weigand <ulrich.weig...@de.ibm.com> > > GCC 6 will include changes to generated code with -mcmodel=large, > which is used to build kernel modules on powerpc64le. This was > necessary because the large model is supposed to allow arbitrary > sizes and locations of the code and data sections, but the ELFv2 > global entry point prolog still made the unconditional assumption > that the TOC associated with any particular function can be found > within 2 GB of the function entry point: > > func: > addis r2,r12,(.TOC.-func)@ha > addi r2,r2,(.TOC.-func)@l > .localentry func, .-func > > To remove this assumption, GCC will now generate instead this global > entry point prolog sequence when using -mcmodel=large: > > .quad .TOC.-func > func: > .reloc ., R_PPC64_ENTRY > ld r2, -8(r12) > add r2, r2, r12 > .localentry func, .-func > > The new .reloc triggers an optimization in the linker that will > replace this new prolog with the original code (see above) if the > linker determines that the distance between .TOC. and func is in > range after all. > > Since this new relocation is now present in module object files, > the kernel module loader is required to handle them too. This > patch adds support for the new relocation and implements the > same optimization done by the GNU linker. > > Cc: sta...@vger.kernel.org > Signed-off-by: Ulrich Weigand <ulrich.weig...@de.ibm.com> > Signed-off-by: Michael Ellerman <m...@ellerman.id.au>
Applied to powerpc next. https://git.kernel.org/powerpc/c/a61674bdfc7c2bf909c4010699 cheers _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
