Re: [PATCH] kernel/module.c: fix warning about unused nowarn variable

From: Corentin Labbe
Date: Tue Jun 06 2017 - 02:39:08 EST


On Mon, Jun 05, 2017 at 10:09:24PM -0700, Jessica Yu wrote:
> +++ Corentin Labbe [02/06/17 14:05 +0200]:
> >This patch fix the following warning:
> >kernel/module.c: In function 'add_usage_links':
> >kernel/module.c:1653:6: warning: variable 'nowarn' set but not used [-Wunused-but-set-variable]
> > int nowarn;
> >
> >Signed-off-by: Corentin Labbe <clabbe.montjoie@xxxxxxxxx>
> >---
> > kernel/module.c | 13 +++++++++----
> > 1 file changed, 9 insertions(+), 4 deletions(-)
> >
> >diff --git a/kernel/module.c b/kernel/module.c
> >index e3e9dbba6a5b..aed902bcb4aa 100644
> >--- a/kernel/module.c
> >+++ b/kernel/module.c
> >@@ -1663,19 +1663,20 @@ static inline void remove_notes_attrs(struct module *mod)
> > }
> > #endif /* CONFIG_KALLSYMS */
> >
> >-static void add_usage_links(struct module *mod)
> >+static int add_usage_links(struct module *mod)
> > {
> >+ int ret = 0;
> > #ifdef CONFIG_MODULE_UNLOAD
> > struct module_use *use;
> >- int nowarn;
> >
> > mutex_lock(&module_mutex);
> > list_for_each_entry(use, &mod->target_list, target_list) {
> >- nowarn = sysfs_create_link(use->target->holders_dir,
> >+ ret = sysfs_create_link(use->target->holders_dir,
> > &mod->mkobj.kobj, mod->name);
>
> ret will get overwritten with each iteration of the loop; we should return
> ret as soon as we hit an error (while making sure we unlock
> module_mutex).
>

Thanks, I will fix all reported errors.
I just found also that in case of error, I need to "del_usage_links"

Regards