datapath: Fix tunnel hashing.

struct port_lookup_key is getting extra 4 bytes due to alignment on x86_64.
That is messing with hash calculation which uses sizeof operator to
calculate key length. Following patch fixes tunnel hashing by using correct
key length.

This bug was introduced by commit f686a33af8cb41ee228e6a35410c9a488fba3eb1
"datapath: Streamline tunnel port lookup"

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Jesse Gross <jesse@nicira.com>
Bug #7622

diff --git a/datapath/tunnel.c b/datapath/tunnel.c
index 100794e0d524b86e2c7c2cb4a2fb4b7589ddb8fa..3576df84c56bde57d2d3c2990c55f0bd4fbd8a66 100644 (file)
--- a/datapath/tunnel.c
+++ b/datapath/tunnel.c
@@ -174,7 +174,7 @@ static unsigned int *find_port_pool(const struct tnl_mutable_config *mutable)
 
 static u32 port_hash(const struct port_lookup_key *key)
 {
-       return jhash2((u32*)key, (sizeof(*key) / sizeof(u32)), 0);
+       return jhash2((u32*)key, (PORT_KEY_LEN / sizeof(u32)), 0);
 }
 
 static inline struct hlist_head *find_bucket(u32 hash)
@@ -241,7 +241,7 @@ static struct tnl_vport *port_table_lookup(struct port_lookup_key *key,
                struct tnl_mutable_config *mutable;
 
                mutable = rcu_dereference_rtnl(tnl_vport->mutable);
-               if (!memcmp(&mutable->key, key, sizeof(*key))) {
+               if (!memcmp(&mutable->key, key, PORT_KEY_LEN)) {
                        *pmutable = mutable;
                        return tnl_vport;
                }

diff --git a/datapath/tunnel.h b/datapath/tunnel.h
index b3e21fa9f3006904518515410e915452fc0de419..e7bafbc94699a8a29a61f2d58ba3131ddf7d747e 100644 (file)
--- a/datapath/tunnel.h
+++ b/datapath/tunnel.h
@@ -58,6 +58,9 @@ struct port_lookup_key {
        u32    tunnel_type;
 };
 
+#define PORT_KEY_LEN   (offsetof(struct port_lookup_key, tunnel_type) + \
+                        FIELD_SIZEOF(struct port_lookup_key, tunnel_type))
+
 /**
  * struct tnl_mutable_config - modifiable configuration for a tunnel.
  * @key: Used as key for tunnel port.  Configured via OVS_TUNNEL_ATTR_*