Re: [PATCH 04/13] livepatch: move klp_find_object_module to module.c

Josh Poimboeuf
2021-01-21T21:48:05Z

On Thu, Jan 21, 2021 at 08:49:50AM +0100, Christoph Hellwig wrote:
> @@ -820,14 +796,25 @@ static int klp_init_object(struct klp_patch *patch, struct klp_object *obj)
> const char *name;
>
> obj->patched = false;
> - obj->mod = NULL;

Why was this line removed?

> if (klp_is_module(obj)) {
> if (strlen(obj->name) >= MODULE_NAME_LEN)
> return -EINVAL;
> name = obj->name;
>
> - klp_find_object_module(obj);
> + /*
> + * We do not want to block removal of patched modules and
> + * therefore we do not take a reference here. The patches are
> + * removed by klp_module_going() instead.
> + *
> + * Do not mess work of klp_module_coming() and
> + * klp_module_going(). Note that the patch might still be
> + * needed before klp_module_going() is called. Module functions
> + * can be called even in the GOING state until mod->exit()
> + * finishes. This is especially important for patches that
> + * modify semantic of the functions.
> + */
> + obj->mod = find_klp_module(obj->name);

These comments don't make sense in this context, they should be kept
with the code in find_klp_module().

--
Josh