[POC 07/23] livepatch: Remove obsolete functionality from klp_module_coming()

From: Petr Mladek
Date: Fri Jan 17 2020 - 10:05:09 EST


klp_module_coming() could not operate on the livepatch structures.
Instead it has to load the livepatch module that will call
klp_add_object().

The functionality has been migrated to klp_add_object() in
the previous commits and the code can be finally removed.

The only exception is mod->klp_alive flag. It will still be needed
to decide who is responsible for loading/removing the eventual
livepatch modules.

It is done this way to make the changes manageable and easier
to review.

Signed-off-by: Petr Mladek <pmladek@xxxxxxxx>
---
kernel/livepatch/core.c | 59 -------------------------------------------------
1 file changed, 59 deletions(-)

diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
index c21bd9ec2012..bb851f916182 100644
--- a/kernel/livepatch/core.c
+++ b/kernel/livepatch/core.c
@@ -1290,10 +1290,6 @@ static void klp_cleanup_module_patches_limited(struct module *mod,

int klp_module_coming(struct module *mod)
{
- int ret;
- struct klp_patch *patch;
- struct klp_object *obj;
-
if (WARN_ON(mod->state != MODULE_STATE_COMING))
return -EINVAL;

@@ -1304,64 +1300,9 @@ int klp_module_coming(struct module *mod)
* get patched by a new patch.
*/
mod->klp_alive = true;
-
- klp_for_each_patch(patch) {
- klp_for_each_object(patch, obj) {
- if (!klp_is_module(obj) || strcmp(obj->name, mod->name))
- continue;
-
- obj->mod = mod;
-
- ret = klp_init_object_loaded(obj);
- if (ret) {
- pr_warn("failed to initialize patch '%s' for module '%s' (%d)\n",
- patch->obj->patch_name, obj->name, ret);
- goto err;
- }
-
- pr_notice("applying patch '%s' to loading module '%s'\n",
- patch->obj->patch_name, obj->name);
-
- ret = klp_pre_patch_callback(obj);
- if (ret) {
- pr_warn("pre-patch callback failed for object '%s'\n",
- obj->name);
- goto err;
- }
-
- ret = klp_patch_object(obj);
- if (ret) {
- pr_warn("failed to apply patch '%s' to module '%s' (%d)\n",
- patch->obj->patch_name, obj->name, ret);
-
- klp_post_unpatch_callback(obj);
- goto err;
- }
-
- if (patch != klp_transition_patch)
- klp_post_patch_callback(obj);
-
- break;
- }
- }
-
mutex_unlock(&klp_mutex);

return 0;
-
-err:
- /*
- * If a patch is unsuccessfully applied, return
- * error to the module loader.
- */
- pr_warn("patch '%s' failed for module '%s', refusing to load module '%s'\n",
- patch->obj->patch_name, obj->name, obj->name);
- mod->klp_alive = false;
- obj->mod = NULL;
- klp_cleanup_module_patches_limited(mod, patch);
- mutex_unlock(&klp_mutex);
-
- return ret;
}

void klp_module_going(struct module *mod)
--
2.16.4