Keep all of tunnel metadata in flow.

Do not clear tunnel metadata on tunnel input.

This is a backport of 4110a57 (Keep all of tunnel metadata in
flow.) to branch-1.11.  This fixes an issue with received tunnel
traffic and megaflows.  xlate_actions() calls tnl_port_should_receive()
to determine whether it should un-wildcard the tunnel fields.  Without
this commit, the original flow's tunnel information is zeroed and is
unavailable for tnl_port_should_receive()'s use to determine whether
it's a tunnel flow or not.  This resulted in some tunnel traffic
being wildcarded inappropriately.

Bug #18277.

Signed-off-by: Justin Pettit <jpettit@nicira.com>
Signed-off-by: Jarno Rajahalme <jarno.rajahalme@nsn.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>

diff --git a/ofproto/ofproto-dpif.c b/ofproto/ofproto-dpif.c
index 93b0579..c1a85b6 100644 (file)
--- a/ofproto/ofproto-dpif.c
+++ b/ofproto/ofproto-dpif.c
@@ -7096,12 +7096,12 @@ xlate_actions(struct xlate_in *xin, struct xlate_out *xout)
      *   to another device without any modifications this will cause us to
      *   insert a new tag since the original one was stripped off by the
      *   VLAN device.
-     * - Tunnel 'flow' is largely cleared when transitioning between
-     *   the input and output stages since it does not make sense to output
-     *   a packet with the exact headers that it was received with (i.e.
-     *   the destination IP is us).  The one exception is the tun_id, which
-     *   is preserved to allow use in later resubmit lookups and loads into
-     *   registers.
+     * - Tunnel metadata as received is retained in 'flow'. This allows
+     *   tunnel metadata matching also in later tables.
+     *   Since a kernel action for setting the tunnel metadata will only be
+     *   generated with actual tunnel output, changing the tunnel metadata
+     *   values in 'flow' (such as tun_id) will only have effect with a later
+     *   tunnel output action.
      * - Tunnel 'base_flow' is completely cleared since that is what the
      *   kernel does.  If we wish to maintain the original values an action
      *   needs to be generated. */

diff --git a/ofproto/tunnel.c b/ofproto/tunnel.c
index ce9def1..9a34d8b 100644 (file)
--- a/ofproto/tunnel.c
+++ b/ofproto/tunnel.c
@@ -197,8 +197,7 @@ tnl_port_receive(struct flow *flow)
     }
 
     flow->in_port = tnl_port->ofport->ofp_port;
-    memset(&flow->tunnel, 0, sizeof flow->tunnel);
-    flow->tunnel.tun_id = match.in_key;
+    /* Keep flow->tunnel to allow matching on tunnel metadata */
 
     if (pre_flow_str) {
         char *post_flow_str = flow_to_string(flow);