batman-adv: Initialize lockdep class keys for hashes
Commit Message
The hash for claim and backbone hash in the bridge loop avoidance code receive
the same key because they are getting initialized by hash_new with the same
key. Lockdep will create a backtrace when they are used recursively. This can
be avoided by reinitializing the key directly after the hash_new.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
---
bridge_loop_avoidance.c | 11 +++++++++++
hash.c | 9 +++++++++
hash.h | 3 +++
3 files changed, 23 insertions(+), 0 deletions(-)
@@ -1124,6 +1124,14 @@ out:
bla_start_timer(bat_priv);
}
+/* The hash for claim and backbone hash receive the same key because they
+ * are getting initialized by hash_new with the same key. Reinitializing
+ * them with to different keys to allow nested locking without generating
+ * lockdep warnings
+ */
+static struct lock_class_key claim_hash_lock_class_key;
+static struct lock_class_key backbone_hash_lock_class_key;
+
/* initialize all bla structures */
int bla_init(struct bat_priv *bat_priv)
{
@@ -1158,6 +1166,9 @@ int bla_init(struct bat_priv *bat_priv)
bat_priv->claim_hash = hash_new(128);
bat_priv->backbone_hash = hash_new(32);
+ hash_set_lock_class(bat_priv->claim_hash, &claim_hash_lock_class_key);
+ hash_set_lock_class(bat_priv->backbone_hash, &backbone_hash_lock_class_key);
+
if (!bat_priv->claim_hash || !bat_priv->backbone_hash)
return -1;
@@ -69,3 +69,12 @@ free_hash:
kfree(hash);
return NULL;
}
+
+void hash_set_lock_class(struct hashtable_t *hash, struct lock_class_key *key)
+{
+ uint32_t i;
+
+ for (i = 0 ; i < hash->size; i++) {
+ lockdep_set_class(&hash->list_locks[i], key);
+ }
+}
@@ -45,6 +45,9 @@ struct hashtable_t {
/* allocates and clears the hash */
struct hashtable_t *hash_new(uint32_t size);
+/* set class key for all locks */
+void hash_set_lock_class(struct hashtable_t *hash, struct lock_class_key *key);
+
/* free only the hashtable and the hash itself. */
void hash_destroy(struct hashtable_t *hash);