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author | Rusty Russell <rusty@rustcorp.com.au> | 2009-12-15 22:28:32 (GMT) |
---|---|---|
committer | Rusty Russell <rusty@rustcorp.com.au> | 2009-12-15 05:58:34 (GMT) |
commit | d4703aefdbc8f9f347f6dcefcddd791294314eb7 (patch) | |
tree | 198936f4f91d6e571548f5b9aba9ee62e93134a6 /kernel/module.c | |
parent | a8773769d1a1e08d0ca15f890515401ab3860637 (diff) | |
download | linux-d4703aefdbc8f9f347f6dcefcddd791294314eb7.tar.xz |
module: handle ppc64 relocating kcrctabs when CONFIG_RELOCATABLE=y
powerpc applies relocations to the kcrctab. They're absolute symbols,
but it's not completely unreasonable: other archs may too, but the
relocation is often 0.
http://lists.ozlabs.org/pipermail/linuxppc-dev/2009-November/077972.html
Inspired-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Tested-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'kernel/module.c')
-rw-r--r-- | kernel/module.c | 28 |
1 files changed, 21 insertions, 7 deletions
diff --git a/kernel/module.c b/kernel/module.c index 12afc5a..a65dc78 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -880,11 +880,23 @@ static int try_to_force_load(struct module *mod, const char *reason) } #ifdef CONFIG_MODVERSIONS +/* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */ +static unsigned long maybe_relocated(unsigned long crc, + const struct module *crc_owner) +{ +#ifdef ARCH_RELOCATES_KCRCTAB + if (crc_owner == NULL) + return crc - (unsigned long)reloc_start; +#endif + return crc; +} + static int check_version(Elf_Shdr *sechdrs, unsigned int versindex, const char *symname, struct module *mod, - const unsigned long *crc) + const unsigned long *crc, + const struct module *crc_owner) { unsigned int i, num_versions; struct modversion_info *versions; @@ -905,10 +917,10 @@ static int check_version(Elf_Shdr *sechdrs, if (strcmp(versions[i].name, symname) != 0) continue; - if (versions[i].crc == *crc) + if (versions[i].crc == maybe_relocated(*crc, crc_owner)) return 1; DEBUGP("Found checksum %lX vs module %lX\n", - *crc, versions[i].crc); + maybe_relocated(*crc, crc_owner), versions[i].crc); goto bad_version; } @@ -931,7 +943,8 @@ static inline int check_modstruct_version(Elf_Shdr *sechdrs, if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL, &crc, true, false)) BUG(); - return check_version(sechdrs, versindex, "module_layout", mod, crc); + return check_version(sechdrs, versindex, "module_layout", mod, crc, + NULL); } /* First part is kernel version, which we ignore if module has crcs. */ @@ -949,7 +962,8 @@ static inline int check_version(Elf_Shdr *sechdrs, unsigned int versindex, const char *symname, struct module *mod, - const unsigned long *crc) + const unsigned long *crc, + const struct module *crc_owner) { return 1; } @@ -984,8 +998,8 @@ static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs, /* use_module can fail due to OOM, or module initialization or unloading */ if (sym) { - if (!check_version(sechdrs, versindex, name, mod, crc) || - !use_module(mod, owner)) + if (!check_version(sechdrs, versindex, name, mod, crc, owner) + || !use_module(mod, owner)) sym = NULL; } return sym; |