Livepatch re-uses module loader function apply_relocate_add() to write relocations, instead of managing them by arch-dependent klp_write_module_reloc() function.
apply_relocate_add() doesn't understand livepatch symbols (marked with SHN_LIVEPATCH symbol section index) and assumes them to be local symbols by default for R_PPC64_REL24 relocation type. It fails with an error, when trying to calculate offset with local_entry_offset(): module_64: kpatch_meminfo: REL24 -1152921504897399800 out of range! Whereas livepatch symbols are essentially SHN_UNDEF, should be called via stub used for global calls. This issue can be fixed by teaching apply_relocate_add() to handle both SHN_UNDEF/SHN_LIVEPATCH symbols via the same stub. This patch extends SHN_UNDEF code to handle livepatch symbols too. Signed-off-by: Kamalesh Babulal <[email protected]> CC: Balbir Singh <[email protected]> Cc: Naveen N. Rao <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Jessica Yu <[email protected]> Cc: Ananth N Mavinakayanahalli <[email protected]> Cc: Aravinda Prasad <[email protected]> Cc: Torsten Duwe <[email protected]> --- arch/powerpc/kernel/module_64.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c index 0b0f896..39b01fd 100644 --- a/arch/powerpc/kernel/module_64.c +++ b/arch/powerpc/kernel/module_64.c @@ -613,7 +613,8 @@ int apply_relocate_add(Elf64_Shdr *sechdrs, case R_PPC_REL24: /* FIXME: Handle weak symbols here --RR */ - if (sym->st_shndx == SHN_UNDEF) { + if (sym->st_shndx == SHN_UNDEF || + sym->st_shndx == SHN_LIVEPATCH) { /* External: go via stub */ value = stub_for_addr(sechdrs, value, me); if (!value) -- 2.9.3
