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From:   "Joel Fernandes (Google)" <joel@joelfernandes.org>
To:     linux-kernel@vger.kernel.org
Cc:     "Joel Fernandes (Google)" <joel@joelfernandes.org>,
        paulmck@kernel.org,
        Rushikesh S Kadam <rushikesh.s.kadam@intel.com>,
        "Uladzislau Rezki (Sony)" <urezki@gmail.com>,
        Neeraj upadhyay <neeraj.iitr10@gmail.com>,
        Frederic Weisbecker <frederic@kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        rcu <rcu@vger.kernel.org>, vineeth@bitbyteword.org
Subject: [PATCH v4 08/14] security: Move call_rcu() to call_rcu_lazy()
Date:   Fri, 19 Aug 2022 20:48:51 +0000
Message-Id: <20220819204857.3066329-9-joel@joelfernandes.org>
In-Reply-To: <20220819204857.3066329-1-joel@joelfernandes.org>
References: <20220819204857.3066329-1-joel@joelfernandes.org>
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This is required to prevent callbacks triggering RCU machinery too
quickly and too often, which adds more power to the system.

Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
---
 security/security.c    | 2 +-
 security/selinux/avc.c | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/security/security.c b/security/security.c
index ea7163c20751..d76f4951b2bd 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1053,7 +1053,7 @@ void security_inode_free(struct inode *inode)
 	 * The inode will be freed after the RCU grace period too.
 	 */
 	if (inode->i_security)
-		call_rcu((struct rcu_head *)inode->i_security,
+		call_rcu_lazy((struct rcu_head *)inode->i_security,
 				inode_free_by_rcu);
 }
 
diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index 9a43af0ebd7d..381f046d820f 100644
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -442,7 +442,7 @@ static void avc_node_free(struct rcu_head *rhead)
 static void avc_node_delete(struct selinux_avc *avc, struct avc_node *node)
 {
 	hlist_del_rcu(&node->list);
-	call_rcu(&node->rhead, avc_node_free);
+	call_rcu_lazy(&node->rhead, avc_node_free);
 	atomic_dec(&avc->avc_cache.active_nodes);
 }
 
@@ -458,7 +458,7 @@ static void avc_node_replace(struct selinux_avc *avc,
 			     struct avc_node *new, struct avc_node *old)
 {
 	hlist_replace_rcu(&old->list, &new->list);
-	call_rcu(&old->rhead, avc_node_free);
+	call_rcu_lazy(&old->rhead, avc_node_free);
 	atomic_dec(&avc->avc_cache.active_nodes);
 }
 
-- 
2.37.2.609.g9ff673ca1a-goog