cgroup: fix RCU related sparse warnings

kn->priv which is a void * is used as a RCU pointer by cgroup.  When
dereferencing it, it was passing kn->priv to rcu_derefreence() without
casting it into a RCU pointer triggering address space mismatch
warning from sparse.  Fix them.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Acked-by: Acked-by: Zefan Li <lizefan@huawei.com>

2 files changed, 2 insertions, 2 deletions

diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c
index 37be09e09740..465b10111eaf 100644
--- a/kernel/cgroup/cgroup-v1.c
+++ b/kernel/cgroup/cgroup-v1.c
@@ -694,7 +694,7 @@ int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry)
          * @kn->priv is RCU safe.  Let's do the RCU dancing.
          */
         rcu_read_lock();
-        cgrp = rcu_dereference(kn->priv);
+        cgrp = rcu_dereference(*(void __rcu __force **)&kn->priv);
         if (!cgrp || cgroup_is_dead(cgrp)) {
                 rcu_read_unlock();
                 mutex_unlock(&cgroup_mutex);
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index b6b9068ef468..d9d82e96d67f 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -4932,7 +4932,7 @@ struct cgroup_subsys_state *css_tryget_online_from_dir(struct dentry *dentry,
          * have been or be removed at any point.  @kn->priv is RCU
          * protected for this access.  See css_release_work_fn() for details.
          */
-        cgrp = rcu_dereference(kn->priv);
+        cgrp = rcu_dereference(*(void __rcu __force **)&kn->priv);
         if (cgrp)
                 css = cgroup_css(cgrp, ss);