[PATCH] Create kallsyms_lookup_size_offset()

Some uses of kallsyms_lookup() do not need to find out the name of a symbol
and its module's name it belongs.  This is specially true in arch specific
code, which needs to unwind the stack to show the back trace during oops
(mips is an example).  In this specific case, we just need to retreive the
function's size and the offset of the active intruction inside it.

Adds a new entry "kallsyms_lookup_size_offset()" This new entry does
exactly the same as kallsyms_lookup() but does not require any buffers to
store any names.

It returns 0 if it fails otherwise 1.

Signed-off-by: Franck Bui-Huu <vagabon.xyz@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/kernel/module.c b/kernel/module.c
index 7c77a0a9275c..7f60e782de1e 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2040,7 +2040,8 @@ const char *module_address_lookup(unsigned long addr,
         list_for_each_entry(mod, &modules, list) {
                 if (within(addr, mod->module_init, mod->init_size)
                     || within(addr, mod->module_core, mod->core_size)) {
-                        *modname = mod->name;
+                        if (modname)
+                                *modname = mod->name;
                         return get_ksymbol(mod, addr, size, offset);
                 }
         }