On Wed, Jun 19, 2019 at 01:33:24PM +0200, Peter Zijlstra wrote:
> How's something like so:
>
> diff --git a/kernel/module.c b/kernel/module.c
> index 80c7c09584cf..eba6560c89da 100644
> --- a/kernel/module.c
> +++ b/kernel/module.c
> @@ -3631,16 +3631,28 @@ static int complete_formation(struct module *mod,
> struct load_info *info)
>
> static int prepare_coming_module(struct module *mod)
> {
> - int err;
> + struct blocking_notifier_head *nh = &module_notify_list;
> + int err, nr;
>
> ftrace_module_enable(mod);
> err = klp_module_coming(mod);
> if (err)
> return err;
>
> - blocking_notifier_call_chain(&module_notify_list,
> - MODULE_STATE_COMING, mod);
> - return 0;
> + if (!rcu_access_pointer(nh->head))
> + return 0;
> +
> + down_read(&nh->rwsem);
> + ret = notifier_call_chain(&nh->head, MODULE_STATE_COMING, mod, -1, &nr);
> + if (ret & NOTIFIER_STOP_MASK)
It compiles _lots_ better with s/ret/err/ on.
> + notifier_call_chain(&nh->head, MODULE_STATE_GOING, mod, nr,
> NULL);
> + up_read(&nh->rwsem);
> +
> + err = notifier_to_err(err);
> + if (err)
> + klp_module_going(mod);
> +
> + return err;
> }
>
> static int unknown_module_param_cb(char *param, char *val, const char
> *modname,
