modules: split part of complete_formation() into prepare_coming_module()

Put all actions in complete_formation() that are performed after
module->state is set to MODULE_STATE_COMING into a separate function
prepare_coming_module(). This split prepares for the removal of the
livepatch module notifiers in favor of hard-coding function calls to
klp_module_{coming,going} in the module loader.

The complete_formation -> prepare_coming_module split will also make error
handling easier since we can jump to the appropriate error label to do any
module GOING cleanup after all the COMING-actions have completed.

Signed-off-by: Jessica Yu <jeyu@redhat.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/kernel/module.c b/kernel/module.c
index 794ebe8..6dbfad4 100644 (file)
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -3392,9 +3392,6 @@ static int complete_formation(struct module *mod, struct load_info *info)
        mod->state = MODULE_STATE_COMING;
        mutex_unlock(&module_mutex);
 
-       ftrace_module_enable(mod);
-       blocking_notifier_call_chain(&module_notify_list,
-                                    MODULE_STATE_COMING, mod);
        return 0;
 
 out:
@@ -3402,6 +3399,14 @@ out:
        return err;
 }
 
+static int prepare_coming_module(struct module *mod)
+{
+       ftrace_module_enable(mod);
+       blocking_notifier_call_chain(&module_notify_list,
+                                    MODULE_STATE_COMING, mod);
+       return 0;
+}
+
 static int unknown_module_param_cb(char *param, char *val, const char *modname,
                                   void *arg)
 {
@@ -3516,13 +3521,17 @@ static int load_module(struct load_info *info, const char __user *uargs,
        if (err)
                goto ddebug_cleanup;
 
+       err = prepare_coming_module(mod);
+       if (err)
+               goto bug_cleanup;
+
        /* Module is ready to execute: parsing args may do that. */
        after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
                                  -32768, 32767, mod,
                                  unknown_module_param_cb);
        if (IS_ERR(after_dashes)) {
                err = PTR_ERR(after_dashes);
-               goto bug_cleanup;
+               goto coming_cleanup;
        } else if (after_dashes) {
                pr_warn("%s: parameters '%s' after `--' ignored\n",
                       mod->name, after_dashes);
@@ -3531,7 +3540,7 @@ static int load_module(struct load_info *info, const char __user *uargs,
        /* Link in to syfs. */
        err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
        if (err < 0)
-               goto bug_cleanup;
+               goto coming_cleanup;
 
        /* Get rid of temporary copy. */
        free_copy(info);
@@ -3541,15 +3550,16 @@ static int load_module(struct load_info *info, const char __user *uargs,
 
        return do_init_module(mod);
 
+ coming_cleanup:
+       blocking_notifier_call_chain(&module_notify_list,
+                                    MODULE_STATE_GOING, mod);
+
  bug_cleanup:
        /* module_bug_cleanup needs module_mutex protection */
        mutex_lock(&module_mutex);
        module_bug_cleanup(mod);
        mutex_unlock(&module_mutex);
 
-       blocking_notifier_call_chain(&module_notify_list,
-                                    MODULE_STATE_GOING, mod);
-
        /* we can't deallocate the module until we clear memory protection */
        module_disable_ro(mod);
        module_disable_nx(mod);