cgroup: grab cgroup_mutex in drop_parsed_module_refcounts()

This isn't strictly necessary as all subsystems specified in
@subsys_mask are guaranteed to be pinned; however, it does spuriously
trigger lockdep warning.  Let's grab cgroup_mutex around it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
This commit is contained in:
Tejun Heo 2013-06-25 18:05:21 -07:00
parent 1672d04070
commit eb178d0633

View file

@ -1325,11 +1325,11 @@ static void drop_parsed_module_refcounts(unsigned long subsys_mask)
struct cgroup_subsys *ss;
int i;
for_each_subsys(ss, i) {
if (!(subsys_mask & (1UL << i)))
continue;
module_put(cgroup_subsys[i]->module);
}
mutex_lock(&cgroup_mutex);
for_each_subsys(ss, i)
if (subsys_mask & (1UL << i))
module_put(cgroup_subsys[i]->module);
mutex_unlock(&cgroup_mutex);
}
static int cgroup_remount(struct super_block *sb, int *flags, char *data)