diff options
| author | Anton Blanchard <anton@samba.org> | 2012-11-26 17:41:08 +0000 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2013-01-10 17:00:31 +1100 |
| commit | 1fbe9cf2598dae3bd464d860bd89c67b1ff8682b (patch) | |
| tree | c07f1fe789777669466bc3077a5f0afa70cf83b6 /arch/powerpc/kernel/module_64.c | |
| parent | 5827d4165ac608d7c26fa68701391e80824ee5c9 (diff) | |
powerpc: Build kernel with -mcmodel=medium
Finally remove the two level TOC and build with -mcmodel=medium.
Unfortunately we can't build modules with -mcmodel=medium due to
the tricks the kernel module loader plays with percpu data:
# -mcmodel=medium breaks modules because it uses 32bit offsets from
# the TOC pointer to create pointers where possible. Pointers into the
# percpu data area are created by this method.
#
# The kernel module loader relocates the percpu data section from the
# original location (starting with 0xd...) to somewhere in the base
# kernel percpu data space (starting with 0xc...). We need a full
# 64bit relocation for this to work, hence -mcmodel=large.
On older kernels we fall back to the two level TOC (-mminimal-toc)
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/kernel/module_64.c')
| -rw-r--r-- | arch/powerpc/kernel/module_64.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c index 9f44a775a106..6ee59a0eb268 100644 --- a/arch/powerpc/kernel/module_64.c +++ b/arch/powerpc/kernel/module_64.c @@ -386,6 +386,14 @@ int apply_relocate_add(Elf64_Shdr *sechdrs, | (value & 0xffff); break; + case R_PPC64_TOC16_LO: + /* Subtract TOC pointer */ + value -= my_r2(sechdrs, me); + *((uint16_t *) location) + = (*((uint16_t *) location) & ~0xffff) + | (value & 0xffff); + break; + case R_PPC64_TOC16_DS: /* Subtract TOC pointer */ value -= my_r2(sechdrs, me); @@ -399,6 +407,28 @@ int apply_relocate_add(Elf64_Shdr *sechdrs, | (value & 0xfffc); break; + case R_PPC64_TOC16_LO_DS: + /* Subtract TOC pointer */ + value -= my_r2(sechdrs, me); + if ((value & 3) != 0) { + printk("%s: bad TOC16_LO_DS relocation (%lu)\n", + me->name, value); + return -ENOEXEC; + } + *((uint16_t *) location) + = (*((uint16_t *) location) & ~0xfffc) + | (value & 0xfffc); + break; + + case R_PPC64_TOC16_HA: + /* Subtract TOC pointer */ + value -= my_r2(sechdrs, me); + value = ((value + 0x8000) >> 16); + *((uint16_t *) location) + = (*((uint16_t *) location) & ~0xffff) + | (value & 0xffff); + break; + case R_PPC_REL24: /* FIXME: Handle weak symbols here --RR */ if (sym->st_shndx == SHN_UNDEF) { |