diff options
author | David S. Miller <davem@davemloft.net> | 2013-05-17 01:32:20 -0700 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2013-05-17 01:32:20 -0700 |
commit | 7ffc37fc358e6298f0e4712c8f82385331303934 (patch) | |
tree | c1947655ac129d0a1aa3212755097baa9600bb3e | |
parent | b0ce3508b25ea6fa10ae3ca254de1d695b521702 (diff) | |
parent | 72822225bd41320a98f5d7cde38317766e18983f (diff) |
Merge tag 'batman-adv-fix-for-davem' of git://git.open-mesh.org/linux-merge
Included changes:
- fix global protection fault by avoiding double call_rcu
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | net/batman-adv/originator.c | 16 | ||||
-rw-r--r-- | net/batman-adv/originator.h | 1 | ||||
-rw-r--r-- | net/batman-adv/translation-table.c | 7 |
3 files changed, 23 insertions, 1 deletions
diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c index 2f3452546636..fad1a2093e15 100644 --- a/net/batman-adv/originator.c +++ b/net/batman-adv/originator.c @@ -156,12 +156,28 @@ static void batadv_orig_node_free_rcu(struct rcu_head *rcu) kfree(orig_node); } +/** + * batadv_orig_node_free_ref - decrement the orig node refcounter and possibly + * schedule an rcu callback for freeing it + * @orig_node: the orig node to free + */ void batadv_orig_node_free_ref(struct batadv_orig_node *orig_node) { if (atomic_dec_and_test(&orig_node->refcount)) call_rcu(&orig_node->rcu, batadv_orig_node_free_rcu); } +/** + * batadv_orig_node_free_ref_now - decrement the orig node refcounter and + * possibly free it (without rcu callback) + * @orig_node: the orig node to free + */ +void batadv_orig_node_free_ref_now(struct batadv_orig_node *orig_node) +{ + if (atomic_dec_and_test(&orig_node->refcount)) + batadv_orig_node_free_rcu(&orig_node->rcu); +} + void batadv_originator_free(struct batadv_priv *bat_priv) { struct batadv_hashtable *hash = bat_priv->orig_hash; diff --git a/net/batman-adv/originator.h b/net/batman-adv/originator.h index 7df48fa7669d..734e5a3d8a5b 100644 --- a/net/batman-adv/originator.h +++ b/net/batman-adv/originator.h @@ -26,6 +26,7 @@ int batadv_originator_init(struct batadv_priv *bat_priv); void batadv_originator_free(struct batadv_priv *bat_priv); void batadv_purge_orig_ref(struct batadv_priv *bat_priv); void batadv_orig_node_free_ref(struct batadv_orig_node *orig_node); +void batadv_orig_node_free_ref_now(struct batadv_orig_node *orig_node); struct batadv_orig_node *batadv_get_orig_node(struct batadv_priv *bat_priv, const uint8_t *addr); struct batadv_neigh_node * diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c index 5e89deeb9542..9e8748575845 100644 --- a/net/batman-adv/translation-table.c +++ b/net/batman-adv/translation-table.c @@ -144,7 +144,12 @@ static void batadv_tt_orig_list_entry_free_rcu(struct rcu_head *rcu) struct batadv_tt_orig_list_entry *orig_entry; orig_entry = container_of(rcu, struct batadv_tt_orig_list_entry, rcu); - batadv_orig_node_free_ref(orig_entry->orig_node); + + /* We are in an rcu callback here, therefore we cannot use + * batadv_orig_node_free_ref() and its call_rcu(): + * An rcu_barrier() wouldn't wait for that to finish + */ + batadv_orig_node_free_ref_now(orig_entry->orig_node); kfree(orig_entry); } |