Hi Laurent,
> 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).
Adding Rusty since he maintains the module loader code.
Anton
> Signed-off-by: Laurent Dufour <lduf...@linux.vnet.ibm.com>
> Cc: Anton Blanchard <an...@samba.org>
> ---
> arch/powerpc/kernel/module_64.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/kernel/module_64.c
> b/arch/powerpc/kernel/module_64.c index 077d2ce..a80c933 100644
> --- a/arch/powerpc/kernel/module_64.c
> +++ b/arch/powerpc/kernel/module_64.c
> @@ -315,8 +315,15 @@ 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));
> + /* 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;
> + }
> }
>
> /* Undefined symbols which refer to .funcname, hack to funcname
> (or .TOC.) */
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