From eb178d063324d9c30f673db3877b892a48ade21e Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 25 Jun 2013 18:05:21 -0700 Subject: [PATCH] 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 Acked-by: Li Zefan --- kernel/cgroup.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/kernel/cgroup.c b/kernel/cgroup.c index e801ecfa36ef..2d3a132e881d 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -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) -- 2.34.1