From c2cbcf533a1d7443cf1d6aae1127491792601587 Mon Sep 17 00:00:00 2001 From: Laurent Dufour Date: Tue, 24 Jun 2014 10:53:59 +0200 Subject: [PATCH] powerpc/module: Fix TOC symbol CRC The commit 71ec7c55ed91 introduced the magic symbol ".TOC." for ELFv2 ABI. This symbol is built manually and has no CRC value computed. A zero value is put in the CRC section to avoid modpost complaining about a missing CRC. Unfortunately, this breaks the kernel module loading when the kernel is relocated (kdump case for instance) because of the relocation applied to the kcrctab values. This patch compute a CRC value for the TOC symbol which will match the one compute by the kernel when it is relocated - aka '0 - relocate_start' done in maybe_relocated called by check_version (module.c). Signed-off-by: Laurent Dufour Cc: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/module_64.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c index 077d2ce6c5a7..d807ee626af9 100644 --- a/arch/powerpc/kernel/module_64.c +++ b/arch/powerpc/kernel/module_64.c @@ -315,8 +315,17 @@ static void dedotify_versions(struct modversion_info *vers, struct modversion_info *end; for (end = (void *)vers + size; vers < end; vers++) - if (vers->name[0] == '.') + if (vers->name[0] == '.') { memmove(vers->name, vers->name+1, strlen(vers->name)); +#ifdef ARCH_RELOCATES_KCRCTAB + /* The TOC symbol has no CRC computed. To avoid CRC + * check failing, we must force it to the expected + * value (see CRC check in module.c). + */ + if (!strcmp(vers->name, "TOC.")) + vers->crc = -(unsigned long)reloc_start; +#endif + } } /* Undefined symbols which refer to .funcname, hack to funcname (or .TOC.) */