rconn: Maintain original allowed_versions instead of substituting for zero.

rconn_create() was substituting OFPUTIL_DEFAULT_VERSIONS if an
allowed_versions of 0 was passed in.  At the same time,
connmgr_set_controllers() compared the adjusted value of allowed_versions
against the original value, saw that they were different, and concluded
that it should kill off and recreate the rconn with the "corrected"
allowed_versions.

This commit fixes the problem by no longer adjusting allowed_versions.
There is no need, because it is only used in contexts where the original
version is OK.

This problem was introduced by commit 90ef0206ea8f5a39 (connmgr:
Reinitialise controllers if protocols changes).

Bug #14126.
CC: Simon Horman <horms@verge.net.au>
Reported-by: Natasha Gude <natasha@nicira.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>

diff --git a/lib/rconn.c b/lib/rconn.c
index 45a0acd..2396e44 100644 (file)
--- a/lib/rconn.c
+++ b/lib/rconn.c
@@ -174,10 +174,10 @@ static bool rconn_logging_connection_attempts__(const struct rconn *);
  *
  * Connections made by the rconn will automatically negotiate an OpenFlow
  * protocol version acceptable to both peers on the connection.  The version
- * negotiated will be one of those in the 'allowed_versions' bitmap:
- * version 'x' is allowed if allowed_versions & (1 << x) is nonzero.  If
- * 'allowed_versions' is zero, then OFPUTIL_DEFAULT_VERSIONS are allowed.
- **/
+ * negotiated will be one of those in the 'allowed_versions' bitmap: version
+ * 'x' is allowed if allowed_versions & (1 << x) is nonzero.  (The underlying
+ * vconn will treat an 'allowed_versions' of 0 as OFPUTIL_DEFAULT_VERSIONS.)
+ */
 struct rconn *
 rconn_create(int probe_interval, int max_backoff, uint8_t dscp,
              uint32_t allowed_versions)
@@ -218,9 +218,7 @@ rconn_create(int probe_interval, int max_backoff, uint8_t dscp,
     rconn_set_dscp(rc, dscp);
 
     rc->n_monitors = 0;
-    rc->allowed_versions = allowed_versions
-        ? allowed_versions
-        : OFPUTIL_DEFAULT_VERSIONS;
+    rc->allowed_versions = allowed_versions;
 
     return rc;
 }